Tootfinder

〰️ Researchers make key gains in unlocking the promise of compact X-ray free-electron lasers
#laser

Researchers make key gains in unlocking the promise of compact X-ray free-electron lasers
New research by scientists from the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), in collaboration with scientists from TAU Systems Inc., has brought the promise of smaller and more affordable X-ray free-electron lasers one step closer to reality.

Single-shot sorting of M\"ossbauer time-domain data at X-ray free electron lasers
Miriam Gerharz, Willi Hippler, Berit Marx-Glowna, Sakshath Sadashivaiah, Kai S. Schulze, Ingo Uschmann, Robert L\"otzsch, Kai Schlage, Sven Velten, Dominik Lentrodt, Lukas Wolff, Olaf Leupold, Ilya Sergeev, Hans-Christian Wille, Cornelius Strohm, Marc Guetg, Shan Liu, Gianluca Aldo Geloni, Ulrike Boesenberg, J\"org Hallmann, Alexey Zozulya, Jan-Etienne Pudell, Angel Rodriguez-Fernandez, Moh…

Single-shot sorting of Mössbauer time-domain data at X-ray free electron lasers
Mössbauer spectroscopy is widely used to study structure and dynamics of matter with remarkably high energy resolution, provided by the narrow nuclear resonance line widths. However, the narrow width implies low count rates, such that experiments commonly average over extended measurement times or many x-ray pulses (``shots''). This averaging impedes the study of non-equilibrium phenomena. It has been suggested that X-ray free-electron lasers (XFELs) could enable Mössbauer single-shot measure…

The Roadmap of New Capabilities of High-Intensity Lasers in Material Design and Manipulation
Alexander V. Bulgakov, Yury V. Ryabchikov, Yoann Levy, Nathan T. Goodfriend, Inam Mirza, Petr Hauschwitz, Vladimir A. Volodin, Martin Divoky, Carlos Do\~nate-Buend\'ia, Bilal G\"okce, Nadezhda M. Bulgakova
https://arxiv.org/abs/2509.17662

The Roadmap of New Capabilities of High-Intensity Lasers in Material Design and Manipulation
One of the current trends of laser applications in material science is using high-intensity lasers to provide fast and efficient surface or volume modifications for achieving controllable material properties, synthesis of novel materials with desired functionalities, and upscaling laser technologies with industry-demanded throughputs. Depending on the parameters, lasers can offer versatile solutions for scientific and industrial applications, starting from exploring the fundamental physics of w…

⚡ Ukraine vs Russia: drones, lasers, and a new alliance that shocked the world! | News Pulse: https://benborges.xyz/2025/09/18/ukraine-vs-russia-drones-lasers.html

Today, Maker Forums Discourse came under fairly heavy spam attack. It took me almost two hours to clean up and shore up our defenses a bit against the next wave.
This attack came from IPs all over the globe, not just from a few poorly-administered ASNs in the developing world as has sometimes happened in the past. One account name made it clear that this was a Fiverr job. 😭
Shout out to

Trump’s ‘Golden Dome’ defence plan includes space missiles, lasers: Report | Donald Trump News | Al Jazeera
https://www.aljazeera.com/news/2025/8/13/trumps-golden-dome-defence-plan-includes-space-missiles-lasers-report?traffic_source=rss

At 9:35 PM CST tonight I saw a brilliant bolide meteor ☄️ blaze straight overhead in downtown #Nashville…right in the middle of an outdoor concert, under planes, lasers, and brutal light pollution. Nobody else noticed it🤦‍♂️, but I knew what I saw.
Luckily my friend Marc, 21 miles north of the city, with an all-sky cam, caught it crystal clear! Sharing both his original and enhanced frames…

France-based Scintil Photonics, which is developing integrated photonic system-on-chips for AI infrastructure, raised a $58M Series B led by Yotta and NGP (Tamara Djurickovic/Tech.eu)
https://tech.eu/2025/09/09/scintil-photonics-secure…

Scintil Photonics secured $58M to scale integrated photonics for AI factories
Grenoble-based Scintil Photonics, a company developing integrated Photonic System-on-Chip (PSoC) solutions for AI infrastructure, has closed a $58 million Series B round. The funding will drive global hiring, accelerate production, and expand its international footprint as it launches the industry’s first single-chip DWDM light engine. Built on its proprietary SHIP™ (Scintil Heterogeneous Integration Photonics) process, Scintil’s technology integrates lasers, photodiodes, and modula…

The birefringent spin-laser as a system of coupled harmonic oscillators
Velimir Labinac, Jiayu David Cao, Gaofeng Xu, Igor \v{Z}uti\'c
https://arxiv.org/abs/2508.01945 https…

The birefringent spin-laser as a system of coupled harmonic oscillators
Adding spin-polarized carriers to semiconductor lasers strongly changes their properties and, through the transfer of angular momentum, leads to the emission of the circularly polarized light. In such spin-lasers the polarization of the emitted light can be modulated an order of magnitude faster than its intensity in the best conventional lasers. This ultrafast operation in spin-lasers relies on the large linear birefringence, usually viewed as detrimental in spin and conventional lasers, which…

Theoretical Detailed Analyses for DC readout and a Fabri-P\'erot gravitational-wave detector
Kouji Nakamura
https://arxiv.org/abs/2508.11098 https://ar…

Theoretical Detailed Analyses for DC readout and a Fabri-Pérot gravitational-wave detector
The quantum expectation value and the stationary noise spectral density for a Fabri-Pérot gravitational-wave detector with a DC readout scheme are discussed in detail only through the quantum electrodynamics of lasers and the Heisenberg equations of mirrors' motion. We demonstrate that the initial conditions of the mirrors' motion concentrate around the fundamental frequency of the pendulum and are not related to the frequency range of our interest. Although in the ideal case, there is a conse…

Detection of Spaceborne Lasers with the Pierre Auger Observatory
Michael Unger (for the Pierre Auger Collaboration), Oliver Lux, Oliver Reitebuch
https://arxiv.org/abs/2508.04510

Detection of Spaceborne Lasers with the Pierre Auger Observatory
The detection of side-scattered ultraviolet light from spaceborne lasers with fluorescence telescopes of cosmic ray observatories offers unique opportunities for systematic studies of the aerosol content of the local atmosphere. It also enables the validation of the optical calibration of the telescopes. Additionally, these observations provide valuable ground-based monitoring of the performance of the scientific instruments aboard satellites used for Earth climate observation. Here, we report …

Worldline Modeling of Ultra-Intense Lasers for N-photon Scattering Processes
Ivan Ahumada, Patrick Copinger, James P. Edwards, Karthik Rajeev
https://arxiv.org/abs/2508.00105 ht…

Worldline Modeling of Ultra-Intense Lasers for N-photon Scattering Processes
The modeling of present and future ultra-intense lasers demands techniques that go beyond the standard diagrammatic approach to non-perturbatively fully capture the effects of strong fields. We illustrate the first-quantized path integral representation for strong-field quantum electrodynamics as a means of accessing the laser being treated as a background field, which is treated without recourse to perturbation theory. We examine an all-multiplicity construction for $N-$photon scattering proce…

Clean room romantic of an electrical engineer overseeing EUV lasers, pieu pieu, ie, #chip manufacturing:
"That overseer needs to wear a clean-room suit, and they have to work an eight-hour shift without a bathroom, food or water break (because getting out of the suit means going through an airlock means shutting down the system means long delays and wastage)."

Theoretical analysis of optical feedback-controlled emission of dual-wavelength lasers
Mathieu Ladouce, Pablo Marin-Palomo, Martin Virte
https://arxiv.org/abs/2509.09246 https:/…

Theoretical analysis of optical feedback-controlled emission of dual-wavelength lasers
Dual and multi-wavelength lasers, i.e., lasers with the ability to emit at two or more wavelengths in a controlled fashion, represent an exciting new twist in laser physics. Harnessing the mode competition to control them better remains, however, a challenge. In this work, we numerically explore the effect of optical feedback on the emission properties of a dual-wavelength laser using a rate equation model. We focus on switching capability and investigate the impact of key laser and feedback pa…

@… seeking an earlier toot about lasers led me to this:
https://mastodon.bsd.cafe/@futuroprossimo@mastodon.uno/115343554122658751
–…

Broadband femtosecond lasers enable efficient two-photon excitation of the ultranarrow linewidth singlet 1s2s state in helium
Shashank Kumar, Justin D. Piel, Chris H. Greene, Niranjan Shivaram
https://arxiv.org/abs/2509.13619

Scaling Laws in Plasma Channels for Laser Wakefield Accelerators
Tianliang Zhang, Jianyi Liu, Shuang Liu, Ran Li, Fei Li, Jianfei Hua, Wei Lu
https://arxiv.org/abs/2508.11238 ht…

Scaling Laws in Plasma Channels for Laser Wakefield Accelerators
Preformed plasma channels are essential for guiding high-power laser pulses over extended distances in laser wakefield accelerators, enabling the generation of multi-GeV electron beams for applications such as free-electron lasers and particle colliders. Above-threshold ionization heating provides a robust mechanism for creating laser-matched plasma channels across a wide parameter range, owing to its density- and geometry-independent heating effect. Establishing predictive scaling laws between…

New article about “watching electrons” during a chemical reaction at Stanford. Amazing.
Article by Dr. Haiwang Yong:
#Lasers

From Lasers to Photon Bose--Einstein Condensates: A Unified Description via an Open-Dissipative Bose--Einstein Distribution
Joshua Krau{\ss}, Enrico Stein, Axel Pelster
https://arxiv.org/abs/2510.05917

From Lasers to Photon Bose--Einstein Condensates: A Unified Description via an Open-Dissipative Bose--Einstein Distribution
Photon condensation was first experimentally realized in 2010 within a dye-filled microcavity at room temperature. Since then, interest in the field has increased significantly, as a photon Bose-Einstein condensate (BEC) represents a prototypical driven-dissipative system. Here, we investigate how its inherent open nature influences the condensation process both quantitatively and qualitatively. To this end, we consider a mean-field model, which can be derived microscopically from a Lindblad ma…

Multi-color XFEL pulses with variable color separation and time delay for multi-frame diffraction imaging
Xiaodan Liu, Hanxiang Yang, Bingyang Yan, Yue Wang, Nanshun Huang, Liqi Han, Jie Cai, Han Wen, Jinqing Yu, Haixiao Deng, Xueqing Yan
https://arxiv.org/abs/2509.14906

Multi-color XFEL pulses with variable color separation and time delay for multi-frame diffraction imaging
X-ray free-electron lasers (XFELs) of high brightness have opened new opportunities for exploring ultrafast dynamical processes in matter, enabling imaging and movies of single molecules and particles at atomic resolution. In this paper, we present a straightforward method for multi-frame diffraction imaging, using the same electron beam to generate four-color XFEL pulses with adjustable wavelength separation and time delay. The optical klystron scheme is introduced to enhance FEL intensity and…

Mid-infrared LEDs based on lattice-mismatched hybrid IV-VI/III-V heterojunctions
Jarod E. Meyer, Biridiana Rodriguez, Leland Nordin, Kunal Mukherjee
https://arxiv.org/abs/2508.09703

Mid-infrared LEDs based on lattice-mismatched hybrid IV-VI/III-V heterojunctions
Light-emitting diodes (LEDs) can bridge the gap between narrow linewidth, expensive lasers and broadband, inefficient thermal globars for low-cost chemical sensing in the mid-infrared (mid-IR). However, the efficiency of III-V based mid-IR LEDs at room temperature is low, primarily limited by strong nonradiative Auger-Meitner recombination that is only partially overcome with complex quantum-engineered active regions. Here, we exploit the intrinsically low Auger Meitner recombination rates of t…

Photonic decision making using optical frequency difference detection in mutually-coupled semiconductor lasers
Hidetoshi Taira, Takatomo Mihana, Shun Kotoku, Andr\'e R\"ohm, Kazutaka Kanno, Atsushi Uchida, Ryoichi Horisaki
https://arxiv.org/abs/2509.12891

Photonic decision making using optical frequency difference detection in mutually-coupled semiconductor lasers
As electronic computing approaches its performance limits, photonic accelerators have emerged as promising alternatives. Photonic accelerators exploiting semiconductor-laser synchronization have been studied for decision-making. While conventional cross-correlation methods are computationally intensive and memory demanding, we propose a frequency-based approach using optical frequency differences. Simulations and experiments confirm that this method achieves decision making with reduced cost an…

Integrated Localization, Mapping, and Communication through VCSEL-Based Light-emitting RIS (LeRIS)
Rashid Iqbal, Dimitrios Bozanis, Dimitrios Tyrovolas, Christos K. Liaskos, Muhammad Ali Imran, George K. Karagiannidis, Hanaa Abumarshoud
https://arxiv.org/abs/2510.08071

Integrated Localization, Mapping, and Communication through VCSEL-Based Light-emitting RIS (LeRIS)
This paper presents a light-emitting reconfigurable intelligent surface (LeRIS) architecture that integrates vertical cavity surface emitting lasers (VCSELs) to jointly support user localization, obstacle-aware mapping, and millimeter-wave (mmWave) communication in programmable wireless environments (PWEs). Unlike prior light-emitting diode (LED)-based LeRIS designs with diffuse emission or LiDAR-assisted schemes requiring bulky sensing modules, the proposed VCSEL-based approach exploits narrow…

Lasers. Near your eyes. What could possibly go wrong?
https://www.extremetech.com/science/metas-new-2mm-laser-display-could-enable-true-ar-glasses

Jiggled interferometer: Ground-based gravitational wave detector using rapidly-repeated free-falling test masses
Shoki Iwaguchi, Bin Wu, Kurumi Umemura, Tomohiro Ishikawa, Kenji Tsuji, Ryota Nishimura, Yuta Michimura, Yutaro Enomoto, Soichiro Morisaki, Yoichi Aso, Tomotada Akutsu, Keiko Kokeyama, Seiji Kawamura
https://arxiv.org/abs/2509.1…

Jiggled interferometer: Ground-based gravitational wave detector using rapidly-repeated free-falling test masses
We propose the Jiggled Interferometer (JIGI), a novel ground-based gravitational wave detector with space-like sensitivity. Using rapidly-repeated free-fall test masses, JIGI eliminates seismic and suspension thermal noise during free fall. Compared to the Juggled Interferometer, it offers improved angular stability and avoids tracking lasers. We analyze detrending--a required step to remove actuation-induced noise--and show sensitivity gains of about four orders of magnitude in the 0.1-0.3 Hz …

Disorder-mediated synchronization resonance in coupled semiconductor lasers
Li-Li Ye, Nathan Vigne, Fan-Yi Lin, Hui Cao, Ying-Cheng Lai
https://arxiv.org/abs/2509.07302 https://…

Disorder-mediated synchronization resonance in coupled semiconductor lasers
The interplay between disorder and synchronization in nonlinear oscillator networks has long been known to give rise to counterintuitive phenomena, such as disorder-enhanced coherence. We uncover a frequency-disorder mediated synchronization resonance in coupled external-cavity semiconductor diode lasers. Specifically, we find that intrinsic random frequency detuning among the lasers can enhance synchronization, reaching a maximum at an optimal coupling strength in the weak-coupling regime. The…

SEPhIA: <1 laser/neuron Spiking Electro-Photonic Integrated Multi-Tiled Architecture for Scalable Optical Neuromorphic Computing
Mat\v{e}j Hejda, Aishwarya Natarajan, Chaerin Hong, Mehmet Berkay On, S\'ebastien d'Herbais de Thun, Raymond G. Beausoleil, Thomas Van Vaerenbergh
https://arxiv.org/abs/2510.07427

SEPhIA: <1 laser/neuron Spiking Electro-Photonic Integrated Multi-Tiled Architecture for Scalable Optical Neuromorphic Computing
Research into optical spiking neural networks (SNNs) has primarily focused on spiking devices, networks of excitable lasers or numerical modelling of large architectures, often overlooking key constraints such as limited optical power, crosstalk and footprint. We introduce SEPhIA, a photonic-electronic, multi-tiled SNN architecture emphasizing implementation feasibility and realistic scaling. SEPhIA leverages microring resonator modulators (MRMs) and multi-wavelength sources to achieve effectiv…

Floquet stability of periodically stationary pulses in a short-pulse fiber laser
Vrushaly Shinglot, John Zweck
https://arxiv.org/abs/2508.02735 https://arx…

Floquet stability of periodically stationary pulses in a short-pulse fiber laser
The quantitative modeling and design of modern short-pulse fiber lasers cannot be performed with averaged models because of large variations in the pulse parameters within each round trip. Instead, lumped models obtained by concatenating models for the various components of the laser are required. Since the optical pulses in lumped models are periodic, their linear stability is investigated using the monodromy operator, which is the linearization of the roundtrip operator about the pulse. A gra…

Notes from the Physics Teaching Lab: Diode Laser Spectroscopy at 658 nm
Kenneth G. Libbrecht
https://arxiv.org/abs/2510.07154 https://arxiv.org/pdf/2510.07…

Notes from the Physics Teaching Lab: Diode Laser Spectroscopy at 658 nm
We describe a teaching-lab experiment that applies basic optical spectroscopy to examine the physics of semiconductor diode lasers. By using a low-power visible laser, this experiment is suitable for use in an open lab environment, where students assemble the spectrometer optics themselves as part of the project. A small holographic grating disperses light onto a camera driving a large display monitor, providing a high-resolution, real-time look at the laser output spectrum. Observing this spec…

Selective excitation of molecular vibrations via a two-mode cavity Raman scheme
Lucas Borges, Thomas Schnappinger, Markus Kowalewski
https://arxiv.org/abs/2509.07753 https://

Selective excitation of molecular vibrations via a two-mode cavity Raman scheme
The experimental realization of strong light-matter coupling with molecules initiated the rapidly evolving field of molecular polaritonics. Most studies focus on how exciton polaritons, which combine electronic excitations with confined light modes, alter photochemistry. In this paper, we investigate their use in selectively exciting molecular vibrational states in the ground state. Selectively exciting molecules to high vibrational states with infrared lasers to catalyze ground-state chemical …

Simulation Study of Energy Chirp Induced Effects in Laser Wakefield Accelerator Driven Free Electron Laser
Shan-You Teng, Wai-Keung Lau, Shih-Hung Chen, Wei-Yuan Chiang
https://arxiv.org/abs/2508.11852

Simulation Study of Energy Chirp Induced Effects in Laser Wakefield Accelerator Driven Free Electron Laser
Beam energy compression via chicane magnets has been proved to be an effective method to reduce the slice energy spread of electron beams generated by laser wakefield accelerators (LWFAs). This technique has been widely adopted by leading research teams in experiments targeting future compact, high-gain free electron lasers (FELs). However, after energy compression, a strong beam energy chirp is introduced into the electron beam, which substantially hinders the microbunching process and impairs…

High-pulse-energy integrated mode-locked lasers based on a Mamyshev oscillator
Zheru Qiu, Jianqi Hu, Xuan Yang, Zhongshu Liu, Yichi Zhang, Xinru Ji, Jiale Sun, Grigorii Likhachev, Xurong Li, Zihan Li, Ulrich Kentsch, Tobias J. Kippenberg
https://arxiv.org/abs/2509.05133

High-pulse-energy integrated mode-locked lasers based on a Mamyshev oscillator
Ultrafast lasers have unlocked numerous advances across science and technology: they enable corneal surgery, reveal chemical reaction dynamics, and underpin optical atomic clocks. Over the past decades, extensive efforts have been devoted to developing photonic integrated circuit-based mode-locked lasers that are compact, scalable, and compatible with further on-chip functionalities. Yet, existing implementations fall short of pulse energies required for their subsequent uses in nonlinear appli…

Experimental End-to-End Optimization of Directly Modulated Laser-based IM/DD Transmission
Sergio Hernandez, Christophe Peucheret, Francesco Da Ros, Darko Zibar
https://arxiv.org/abs/2508.19910

Experimental End-to-End Optimization of Directly Modulated Laser-based IM/DD Transmission
Directly modulated lasers (DMLs) are an attractive technology for short-reach intensity modulation and direct detection communication systems. However, their complex nonlinear dynamics make the modeling and optimization of DML-based systems challenging. In this paper, we study the end-to-end optimization of DML-based systems based on a data-driven surrogate model trained on experimental data. The end-to-end optimization includes the pulse shaping and equalizer filters, the bias current and the …

High contrast few-cycle frontend with hybrid amplification for petawatt-class lasers
Roland S. Nagymih\'aly, Mikhail Kalashnikov, Levente Lehotai, Viktor Pajer, J\'anos Bohus, N\'ora Csernus-Luk\'acs, J\'anos Csontos, Szabolcs T\'oth, Bal\'azs Tari, Ignas Balciunas, Ernestas Kucinskas, Tomas Stanislauskas, \'Ad\'am B\"orzs\"onyi

High contrast few-cycle frontend with hybrid amplification for petawatt-class lasers
We present a 10 mJ-class laser system for seeding petawatt-class Ti:Sa lasers based on a hybrid, femtosecond optical parametric and negatively chirped Ti:Sa-based amplification architecture. Output pulses with 13 mJ energy, 14.4 fs transform limited duration, and high spatio-spectral quality are reached at 100 Hz repetition rate centered at 788 nm wavelength. By compressing 1 mJ energy with bulk glass and positively chirped mirrors, a pulse duration of 15.5 fs is measured. The intensity contras…

QVNTVS, Open-Source Quantum Well Simulator
Barbaros \c{S}air
https://arxiv.org/abs/2508.07792 https://arxiv.org/pdf/2508.07792

QVNTVS, Open-Source Quantum Well Simulator
Quantum Wells (QW) are of great importance in optoelectronic devices such as LEDs and LASERs, being the emissive layers.Simulating the quantum particles in different QW topologies like rectangular finite potential wells, multiple potential wells, and triangular biased potential well heterojunctions enables faster modeling, theoretical characterization, and more. QVNTVS performs energy level and wavefunction calculations, recombination probability, transition energy, and optical emission computa…

Theory uncertainties in predictions of strong-field QED
T. G. Blackburn
https://arxiv.org/abs/2508.03975 https://arxiv.org/pdf/2508.03975

Theory uncertainties in predictions of strong-field QED
Experiments using high-power lasers and relativistic electron beams will soon be capable of precision testing of the theory of strong-field quantum electrodynamics. The comparison between experiment and theory always occurs via numerical simulations, but the lack of quantitative uncertainty bounds for the latter means that the origin of any discrepancies cannot be identified conclusively. Here I present a simulation framework that can place meaningful bounds on the theory uncertainties inherent…

Octave Spanning Visible to SWIR Integrated Coil-Stabilized Brillouin Lasers
Meiting Song, Nitesh Chauhan, Mark W. Harrington, Nick Montifiore, Kaikai Liu, Andrew S. Hunter, Chris Caron, Andrei Isichenko, Robert J. Niffenegger, Daniel J. Blumenthal
https://arxiv.org/abs/2508.03036

Octave Spanning Visible to SWIR Integrated Coil-Stabilized Brillouin Lasers
Narrow linewidth stabilized lasers are central to precision applications that operate across the visible to short-wave infrared wavelengths, including optical clocks, quantum sensing and computing, ultra-low noise microwave generation, and fiber sensing. Today, these spectrally pure sources are realized using multiple external cavity tabletop lasers locked to bulk-optic free-space reference cavities. Integration of this technology will enable portable precision applications with improved reliab…

High harmonic generation from a Bose-Einstein condensate
Philipp Stammer
https://arxiv.org/abs/2509.19022 https://arxiv.org/pdf/2509.19022

A continuous-wave vacuum ultraviolet laser for the nuclear clock
Qi Xiao, Gleb Penyazkov, Xiangliang Li, Beichen Huang, Wenhao Bu, Juanlang Shi, Haoyu Shi, Tangyin Liao, Gaowei Yan, Haochen Tian, Yixuan Li, Jiatong Li, Bingkun Lu, Li You, Yige Lin, Yuxiang Mo, Shiqian Ding
https://arxiv.org/abs/2507.19449 https://arxiv.org/pdf/2507.19449 https://arxiv.org/html/2507.19449
arXiv:2507.19449v1 Announce Type: new
Abstract: The exceptionally low-energy isomeric transition in $^{229}$Th at around 148.4 nm offers a unique opportunity for coherent nuclear control and the realisation of a nuclear clock. Recent advances, most notably the incorporation of large ensembles of $^{229}$Th nuclei in transparent crystals and the development of pulsed vacuum-ultraviolet (VUV) lasers, have enabled initial laser spectroscopy of this transition. However, the lack of an intense, narrow-linewidth VUV laser has precluded coherent nuclear manipulation. Here we introduce and demonstrate the first continuous-wave laser at 148.4 nm, generated via four-wave mixing (FWM) in cadmium vapor. The source delivers 100 nW of power with a linewidth well below 100 Hz and supports broad wavelength tunability. This represents a five-orders-of-magnitude improvement in linewidth over all previous single-frequency lasers below 190 nm, marking a major advance in laser technology. We develop a spatially resolved homodyne technique to place a stringent upper bound on the phase noise induced by the FWM process and demonstrate sub-hertz linewidth capability. These results eliminate the final technical hurdle to a $^{229}$Th-based nuclear clock, opening new directions in quantum metrology, nuclear quantum optics and precision tests of the Standard Model. More broadly, they establish a widely tunable, ultranarrow-linewidth laser platform for applications across quantum information science, condensed matter physics, and high-resolution VUV spectroscopy.
toXiv_bot_toot

Control of cross-beam energy transfer through laser-plasma parameter adjustment
Yilin Xu, Yao Zhao, Hongwei Yin, Zhuwen Lin, Yan Yin, Liang Hao, Yaozhi Yi, Hongyu Zhou, Jinlong Jiao, Anle Lei
https://arxiv.org/abs/2508.03152

Control of cross-beam energy transfer through laser-plasma parameter adjustment
Cross-beam energy transfer (CBET) between two lasers is investigated through both analytical theory and two-dimensional simulations, with particular attention to its linear and nonlinear evolution under various laser-plasma conditions over timescales from several hundred picoseconds to one nanosecond. Based on the dispersion relation of stimulated Brillouin scattering driven by two laser beams, we obtain a laser frequency difference range within which CBET occurs. In the nonlinear regime, high …

Interactions in Rare Earth Doped Nanoparticles: A Multi-Transition, Concentration, and Excitation Path Analysis
Pauline Perrin, Luiz Fernando Dos Santos, Diana Serrano, Alexey Tiranov, Jocelyn Achard, Alexandre Tallaire, Rog\'eria R. Gon\c{c}alves, Philippe Goldner
https://arxiv.org/abs/2509.04233

Interactions in Rare Earth Doped Nanoparticles: A Multi-Transition, Concentration, and Excitation Path Analysis
Understanding and modeling energy transfer mechanisms in rare-earth-doped nanomaterials is essential for advancing luminescent technologies used in bioimaging, optical thermometry, and solid-state lasers. In this work, we investigate the photoluminescence dynamics of Yb3+ and Er3+ ions in Y2O3 nanoparticles over a wide concentration range (0.5-17%), using both direct and upconversion excitation. Luminescence decays of green, red, and near-infrared transitions were measured and analyzed using a …

Replaced article(s) found for nucl-ex. https://arxiv.org/list/nucl-ex/new
[1/1]:
- A new scheme for isomer pumping and depletion with high-power lasers
C. -J. Yang, K. M. Spohr, M. Cernaianu, D. Doria, P. Ghenuche, V. Horny

Rabi Oscillations Modulated Noise Squeezing in Active Quantum Dot Ensembles
Ori Gabai, Amnon Willinger, Igor Khanonkin, Vitalii Sichkovskyi, Johann Peter Reithmaier, Gadi Eisenstein
https://arxiv.org/abs/2508.07890

Rabi Oscillations Modulated Noise Squeezing in Active Quantum Dot Ensembles
Generation of squeezed light is usually implemented in nonlinear \c{hi}(2) or \c{hi}(3) materials. Semiconductor lasers and optical amplifiers (SOAs) also offer non-linearities but they differ from passive elements in that they add amplified spontaneous emission noise (ASE). In a semiconductor laser, squeezing to below the shot noise limit has been demonstrated. An SOA contains no cavity and it adds significant noise. Gain saturation can lead, in principle, to squeezing of the photon number qua…

Monte Carlo challenges for strong field quantum electrodynamics
Anthony Hartin
https://arxiv.org/abs/2509.05119 https://arxiv.org/pdf/2509.05119

Monte Carlo challenges for strong field quantum electrodynamics
The assisted Schwinger effect, which is predicted to display non-perturbative quantum tunnelling, is expected to be produced in precision lab experiments with electron beams and intense lasers. Indeed, many novel effects predicted by a theory which incorporates the laser field exactly, can be probed experimentally with the proper application of theory and simulation. Among predicted first order effects are a rest mass shift and harmonic Compton scattering. Higher order effects include resonant …

Attosecond-level synchronisation of chip-integrated oscillators
Alexander E. Ulanov, Bastian Ruhnke, Thibault Wildi, Tobias Herr
https://arxiv.org/abs/2510.11630 https://…

Attosecond-level synchronisation of chip-integrated oscillators
Attosecond science provides a window to the fastest processes in chemistry, materials science, and biology. Accessing this time scale requires precisely synchronised oscillators. In free-electron X-ray lasers, which also provide sub-atomic resolution, synchronisation must be achieved across hundreds of meters. Current approaches to synchronisation based on mode-locked lasers deliver this level of performance but complexity, cost and size hinder their deployment in facility-wide multi-node netwo…

Frequency stability of $2.5\times10^{-17}$ in a Si cavity with AlGaAs crystalline mirrors
Dahyeon Lee, Zoey Z. Hu, Ben Lewis, Alexander Aeppli, Kyungtae Kim, Zhibin Yao, Thomas Legero, Daniele Nicolodi, Fritz Riehle, Uwe Sterr, Jun Ye
https://arxiv.org/abs/2509.13503

Frequency stability of $2.5\times10^{-17}$ in a Si cavity with AlGaAs crystalline mirrors
Developments in ultrastable lasers have fueled remarkable advances in optical frequency metrology and quantum science. A key ingredient in further improving laser frequency stability is the use of low-noise mirror materials such as AlGaAs crystalline coatings. However, excess noise observed with these coatings limits the performance of cryogenic silicon cavities with AlGaAs mirrors to similar levels achieved with conventional dielectric coatings. With a new pair of crystalline coated mirrors in…

Practical security of local local oscillator continuous-variable quantum key distribution systems with pulse width mismatch
Yi Zheng, Jiarui Wu, Chenlei Fang, Qingbing Ji, Wei Pan, Haobin Shi
https://arxiv.org/abs/2509.26021

Practical security of local local oscillator continuous-variable quantum key distribution systems with pulse width mismatch
In continuous-variable quantum key distribution (CVQKD) systems, using a local local oscillator (LLO) scheme removes the local oscillator side channel, enhances Bob's detection performance and reduces the excess noise caused by photon leakage, thereby effectively improves the system's security and performance. However, in this scheme, since the signal and the LO are generated by different lasers and the signal propagates through the untrusted quantum channel, their pulse widths may become misma…

Crosslisted article(s) found for physics.chem-ph. https://arxiv.org/list/physics.chem-ph/new
[1/1]:
- A Path towards Thresholdless Colloidal Quantum Dot Lasers by Solving Decades of Mythology on Opti...
Davide Zenatti, Patanjali Kambhampati

Time Crystals in Actively Mode-locked Lasers
Ruiling Weng, Elias R. Koch, Jes\'us Yelo-Sarri\'on, Josep Batle, Neil G. R. Broderick, Julien Javaloyes, Svetlana V. Gurevich
https://arxiv.org/abs/2509.09230

Time Crystals in Actively Mode-locked Lasers
We report the first experimental observation of discrete time-crystal phases and crystallites in an actively mode-locked semiconductor laser. By tuning either the bias current or the modulation frequency, the system undergoes a spontaneous symmetry-breaking transition from the harmonically mode-locked state towards robust, highly coherent time-crystal states that persist indefinitely. Two equivalent time-crystal configurations, shifted by one driving period, can coexist as domains separated by …

Crosslisted article(s) found for physics.plasm-ph. https://arxiv.org/list/physics.plasm-ph/new
[1/1]:
- Holographic Gaseous Lenses for High-Power Lasers
Devdigvijay Singh, et al.

Accurate Modelling of Intrabeam Scattering and its Impact on Photoinjectors for Free-Electron Lasers
Thomas Geoffrey Lucas, Paolo Craievich, Eduard Prat, Sven Reiche, Erion Gjonaj
https://arxiv.org/abs/2510.02058

Accurate Modelling of Intrabeam Scattering and its Impact on Photoinjectors for Free-Electron Lasers
Intrabeam scattering (IBS) is a fundamental effect that can limit the performance of high-brightness electron machines, yet it has so far been neglected in standard modelling of RF photoinjectors. Recent measurements at SwissFEL reveal that the slice energy spread (SES) in the injector is significantly underestimated by conventional tracking codes. In this work, we present a dedicated Monte Carlo simulation model that accurately predicts the IBS-induced SES growth in the photoinjector of an X-r…

Holographic Gaseous Lenses for High-Power Lasers
Devdigvijay Singh, Ke Ou, Sida Cao, Victor M. Perez-Ramirez, Harsha Rajesh, Debolina Chakraborty, Caleb Redshaw, Pelin Dedeler, Albertine Oudin, Michelle M. Wang, Julia M. Mikhailova, Livia Lancia, Caterina Riconda, Pierre Michel, Matthew R. Edwards
https://arxiv.org/abs/2510.02659

Holographic Gaseous Lenses for High-Power Lasers
The capabilities of the world's highest energy and peak-power pulsed lasers are limited by optical damage, and further advances in high-intensity laser science will require optics that are substantially more robust than existing components. We describe here the experimental demonstration of off-axis diffractive gaseous lenses capable of withstanding extreme laser fluence and immune to cumulative damage. We used less than 8 mJ of energy from interfering ultraviolet laser pulses to holographicall…

Strong-Field Photoelectron Interferometry with Near-Single-Cycle Yb Lasers
Mahmudul Hasan, Phi-Hung Tran, Jingsong Gao, Van-Hung Hoang, Ming-Shian Tsai, Ming-Chang Chen, Uwe Thumm, Charles Lewis Cocke, Chii-Dong Lin, Anh-Thu Le, and Meng Han
https://arxiv.org/abs/2509.01866

Multi-laser stabilization with an atomic-disciplined photonic integrated resonator
Andrei Isichenko, Andrew S. Hunter, Nitesh Chauhan, John R. Dickson, T. Nathan Nunley, Josiah R. Bingaman, David A. S. Heim, Mark W. Harrington, Kaikai Liu, Paul D. Kunz, Daniel J. Blumenthal
https://arxiv.org/abs/2509.09124

Multi-laser stabilization with an atomic-disciplined photonic integrated resonator
Precision atomic and quantum experiments rely on ultra-stable narrow linewidth lasers constructed using table-top ultra-low expansion reference cavities. These experiments often require multiple lasers, operating at different wavelengths, to perform key steps used in state preparation and measurement required in quantum sensing and computing. This is traditionally achieved by disciplining a cavity-stabilized laser to a key atomic transition and then transferring the transition linewidth and sta…

Agile and Broadband All-Optical Wavelength Conversion with Multi-Wavelength Lasers
Pablo Marin-Palomo, Shahab Abdollahi, Mathieu Ladouce, Martin Virte
https://arxiv.org/abs/2509.08134

Agile and Broadband All-Optical Wavelength Conversion with Multi-Wavelength Lasers
We demonstrate a novel approach to all-optical wavelength conversion (AOWC) using a monolithically integrated InP multi-wavelength laser (MWL). By exploiting carrier-induced gain modulation and intermodal coupling within the common gain section, we achieve data wavelength conversion over a 1.3 THz range for signals up to 10 GBd, without the need for an external probe laser. The scheme relies on optical injection of the data signal into the MWL, where strong mode coupling enables transfer of the…

The essential spectrum of periodically stationary pulses in lumped models of short-pulse fiber lasers
Vrushaly Shinglot, John Zweck
https://arxiv.org/abs/2508.01133 https://

The essential spectrum of periodically stationary pulses in lumped models of short-pulse fiber lasers
In modern short pulse fiber lasers there is significant pulse breathing over each round trip of the laser loop. Consequently, averaged models cannot be used for quantitative modeling and design. Instead, lumped models, which are obtained by concatenating models for the various components of the laser, are required. Since the pulses in lumped models are periodic rather than stationary, their linear stability is evaluated with the aid of the monodromy operator obtained by linearizing the round tr…

Enhanced Axion-Photon Conversion via Seeded Photons instead of Resonant Cavities for Short-Pulse Axion Detection
Xiangyan An, Min Chen, Jianglai Liu, Zhengming Sheng, Jie Zhang
https://arxiv.org/abs/2509.21417

Enhanced Axion-Photon Conversion via Seeded Photons instead of Resonant Cavities for Short-Pulse Axion Detection
We propose a seeded axion-photon conversion scheme to enhance the sensitivity of light-shining-through-wall (LSW) experiments for axion detection, where the axions are generated from short pulse lasers and the usual resonant cavity is not applicable. By injecting a small, coherent seed electromagnetic field (EM field) into the axion-photon conversion region, the axion-induced EM field can constructively interfere with the seed field, amplifying the regenerated photon number beyond the unseeded …

Enhanced White-Light Emission from Self-Trapped Excitons in Antimony and Bismuth Halides through Structural Design
Philip Klement, Lukas G\"umbel, Meng Yang, Jan-Heinrich Littmann, Tatsuhiko Ohto, Hirokazu Tada, Sangam Chatterjee, Johanna Heine
https://arxiv.org/abs/2509.20087

Enhanced White-Light Emission from Self-Trapped Excitons in Antimony and Bismuth Halides through Structural Design
Lead halide perovskites have catalyzed the rise of main-group metal halide materials as promising candidates for next-generation optoelectronics, including solar cells, light-emitting diodes, lasers, sensors, and photocatalysts. Among these, effi-cient light-emission arises from self-trapped excitons, wherein excited states induce transient lattice distortions that localize excitons. However, the complex interplay of factors, such as lattice distortions, lattice softness, and electron-phonon co…

On Space Debris Removal by Lasers: Can Spatially and Temporally Shaped Laser Pulses Be Advantageous for Propulsion?
Nadezhda M. Bulgakova
https://arxiv.org/abs/2509.02862 https:…

On Space Debris Removal by Lasers: Can Spatially and Temporally Shaped Laser Pulses Be Advantageous for Propulsion?
For exploration of space, in particular in attempts to find new extra-terrestrial resources, human society has encountered the problem of space pollution with human-made debris, which represents high risks for space missions. This prompted extensive activities for cleaning the space using various techniques, which are briefly overviewed here. But the main focus of this paper is on using lasers for space debris removal. The attention is drawn to laser beam shaping techniques, which are discussed…

Forward and Backward Electron Acceleration by Radially Polarized Ultra-Intense Laser Focus Seeded By Field Ionization of High Charge States of Neon
Nour El Houda Hissi, Gregory K. Ngirmang, Joseph Smith, Enam A. Chowdhury
https://arxiv.org/abs/2509.01741

Forward and Backward Electron Acceleration by Radially Polarized Ultra-Intense Laser Focus Seeded By Field Ionization of High Charge States of Neon
Thanks to the fabrication of large aperture phase optics, ultra-intense relativistic laser plasma interaction (RLPI) experiments with complex polarization states are becoming feasible. In this work, we perform a computational investigation of direct acceleration of electrons produced during ionization of underdense neon gas using a tightly focused and radially polarized Petawatt-class short pulse lasers by numerically solving the relativistically invariant Lorentz equations, incorporating semi-…

A Path towards Thresholdless Colloidal Quantum Dot Lasers by Solving Decades of Mythology on Optical Gain
Davide Zenatti, Patanjali Kambhampati
https://arxiv.org/abs/2510.01199 …

A Path towards Thresholdless Colloidal Quantum Dot Lasers by Solving Decades of Mythology on Optical Gain
The semiconductor quantum dot (CQD) was first conceived in the 1980s as offering potential for future lasers. Following high quality solution phase synthesis of colloidal CQD (CCQD) in 1993, optical gain was first demonstrated in 2000 via stimulated emission (SE) measurements. Decades of phenomenology have given rise to a Standard Model of optical gain in CCQD based upon two assumptions: a biexciton is required to achieve optical gain, and short biexciton lifetimes limit the efficient developme…

Average-power scalability of multi-cycle terahertz sources based on periodically poled lithium niobate stacks
Patrick J. Dalton, Robin L\"oscher, Tim Vogel, Robert B. Appleby, Graeme Burt, Steven P. Jamison, Morgan T. Hibberd, Darren M. Graham, Clara J. Saraceno
https://arxiv.org/abs/2509.13060

Average-power scalability of multi-cycle terahertz sources based on periodically poled lithium niobate stacks
We demonstrate that narrowband multi-cycle terahertz (MC-THz) sources based on periodically-poled lithium niobate (PPLN) wafer stacks can be driven by high repetition-rate, high energy femtosecond ytterbium-doped lasers. Operating at 10-kHz repetition rate with up to 104 W of pump power on a 10-wafer stack, we measure 26.4 mW of THz average power for a narrowband multi-cycle source. We identify and quantify strong lensing effects causing dramatic beam focusing in 47 wafer stacks which act as a …

Deeply Subwavelength Blue-Range Nanolaser
Daria Khemelevskaia, Nikolai Solodovchenko, Elizaveta Sapozhnikova, Igor Chestnov, Alexey Dmitriev, Vanik Shahnazaryan, Denis Baranov, Sergey Makarov
https://arxiv.org/abs/2509.13062

Deeply Subwavelength Blue-Range Nanolaser
Modern high-definition display and augmented reality technologies require the development of ultracompact micro- and nano-pixels with colors covering the full gamut and high brightness. In this regard, lasing nano-pixels emitting light in the spectral range 400-700 nm are highly demanded. Despite progress in red, green, and ultraviolet nanolasers, the demonstrated blue-range (400-500 nm) single-particle-based lasers are still not subwavelength yet. Here we fabricate CsPbCl$_3$ cubic-shaped sing…

Control of kinetic plasma instabilities by laser fields
Nicolas Crouseilles, Lukas Einkemmer, Qin Li, Uri Shumlak, Yukun Yue
https://arxiv.org/abs/2509.23080 https://

Control of kinetic plasma instabilities by laser fields
We study the possibility of controlling kinetic plasma instabilities by using lasers to apply external electromagnetic fields. We derive the dispersion relation for the corresponding mathematical description, a reduced Vlasov--Maxwell system, by extending the well-known Penrose condition. It is observed that, under very mild assumptions, the dispersion relation decouples into two parts. The first part is identical to the classic Penrose condition for the Vlasov--Poisson system, while the second…

First demonstration of coherent radiation imaging for bunch-by-bunch longitudinal compression monitoring
Joseph Wolfenden, Ana Guisao-Betancur, Carsten Welsch, Billy Kyle, Thomas Pacey, Erik Mansten, Sara Thorin, Mathias Brandin
https://arxiv.org/abs/2509.04689

First demonstration of coherent radiation imaging for bunch-by-bunch longitudinal compression monitoring
Longitudinal bunch profile monitoring is a crucial diagnostic requirement in most accelerator facilities. This is particularly true in modern free-electron lasers and novel acceleration schemes, where bunch lengths are often <100 fs and standard instrumentation is invasive or lacks the required resolution. This paper proposes a new monitoring method in this challenging parameter space. Initial proof of principle results for relative compression monitoring via broadband imaging of coherent THz r…

Multimode emission of fluorinated ethylene propylene clad large diameter liquid-core lasers
Anand Dewansingh, Abigail Deaton, Cortland Bergman, Hengzhou Liu, Tracy Olin, Nathan J. Dawson
https://arxiv.org/abs/2510.07188

Multimode emission of fluorinated ethylene propylene clad large diameter liquid-core lasers
A liquid-core (LiCo) dye laser was demonstrated using Rhodamine B (RhB) dissolved in glycerol as the gain medium and fluorinated ethylene propylene (FEP) tubing as the waveguide. Photoluminescence and amplified spontaneous emission (ASE) studies identified optimal RhB concentrations of 0.1 wt.% and 0.3 wt.% for low-threshold laser operation. Laser emission was achieved in LiCo rods with 1/16 inch and 1/32 inch inner diameter FEP tubing, with narrower tubing providing enhanced mode confinement a…

The Spontaneous Cascading Mechanism Behind Critical Phenomena in Self-Coupled Lasers
Jiaoqing Wang, Yael Kfir-Cohen, Chenni Xu, Bnaya Gross, Aswathy Sundaresan, Shlomo Havlin, Patrick Sebbah
https://arxiv.org/abs/2508.21786

The Spontaneous Cascading Mechanism Behind Critical Phenomena in Self-Coupled Lasers
The basic physics of lasers is characterized by a second-order continuous phase transition at the critical lasing threshold. Nevertheless, laser bistability with abrupt transitions has been reported in some laser systems, but its underlying mechanism has never been explored. Here we study experimentally and theoretically a novel nonlinearly self-coupled laser system. We show both experimentally and theoretically that this system experiences spontaneous cascading that yields an abrupt mixed-orde…

Far-field directionality control of coupled InP nanowire lasers
Lukas R. J\"ager (Friedrich Schiller University Jena, Australian National University), Wei Wen Wong (Australian National University), Carsten Ronning (Friedrich Schiller University Jena), Hark Hoe Tan (Australian National University)
https://arxiv.org/abs/2507.18416

Far-field directionality control of coupled InP nanowire lasers
Nanowire (NW) lasers hold great promise as compact, coherent on-chip light sources that are crucial for next-generation optical communication and imaging technologies. However, controlling their emission directionality has been hindered by the complexities of lasing mode engineering and fabrication. Here, we demonstrate spatially-engineered far-field emission from vertically emitting InP NW lasers by establishing precise control over the optical coupling between site-selective NWs, without rely…

A laser with instability reaching $4 \times 10^{-17}$ based on a 10-cm-long silicon cavity at sub-5-K temperatures
Zhi-Ang Chen, Hao-Ran Zeng, Wen-Wei Wang, Han Zhang, Run-Qi Lei, Jian-Zhang Li, Cai-Yin Pang, She-Song Huang, Xibo Zhang
https://arxiv.org/abs/2510.06636

A laser with instability reaching $4 \times 10^{-17}$ based on a 10-cm-long silicon cavity at sub-5-K temperatures
The realization of ultra-stable lasers with $10^{-17}$-level frequency stability has enabled a wide range of researches on precision metrology and fundamental science, where cryogenic single-crystalline cavities constitute the heart of such ultra-stable lasers. For further improvements in stability, increasing the cavity length at few-kelvin temperatures provides a promising alternative to utilizing relatively short cavities with novel coating, but has yet to be demonstrated with state-of-the-a…

Sub-5-fs compression and synchronization of relativistic electron bunches enabled by a high-gradient $\alpha$-magnet and low-jitter photoinjector
Yining Yang, Zhiyuan Wang, Peng Lv, Baiting Song, Pengwei Huang, Yanqing Jia, Zhuoxuan Liu, Lianmin Zheng, Wenhui Huang, Pietro Musumeci, Chuanxiang Tang, Renkai Li
https://arxiv.org/abs/2508.039…

Sub-5-fs compression and synchronization of relativistic electron bunches enabled by a high-gradient $α$-magnet and low-jitter photoinjector
Generating high-brightness relativistic electron bunches with few-femtosecond duration, while simultaneously achieving few-fs synchronization with ultrafast lasers, remains an outstanding challenge at the frontier of accelerator physics and ultrafast science. In this Letter, we present the beam physics and experimental demonstration of a new method that, for the first time, enables simultaneous control of bunch duration and synchronization with few-fs precision. Timing stabilization is achieved…

Broadband on-chip SiN lasers
Ken Liu
https://arxiv.org/abs/2508.02347 https://arxiv.org/pdf/2508.02347

Broadband on-chip SiN lasers
Broadband active materials are pivotal for advancing emerging technologies spanning on-chip optical interconnects, artificial intelligence, quantum systems and precision metrology. Current semiconductor gain media face bandwidth limitations; and Ttitanium-doped sapphire (Ti:sapphire), the most widely used broadband light-emitting material, covering the red to short-wave near-infrared (SW-NIR) spectrum, lacking emission in the entire visible range. Here, on-chip integrated silicon nitride (SiN) …

Multipulse Soliton Attractors Facilitated by High-Birefringence Fibers
Xuepeng Wang, Haoyu Feng, Zhentao Ju, Boris A. Malomed, Chaoqing Dai
https://arxiv.org/abs/2508.10274 http…

Multipulse Soliton Attractors Facilitated by High-Birefringence Fibers
The stability of optical solitons is a crucial factor in various applications. This work reveals a novel stable multipulse soliton attractor in fiber lasers. The attractor represents a bound state of multiple solitons, pulling other dynamical states toward itself. By introducing a polarization-maintaining fiber (PMF), the enhanced birefringence in the cavity induces the differential group delay (DGD) between the polarization components of the pulse, leading to soliton splitting and, ultimately,…

Characterization of non-planar ring oscillators at a wavelength of 1064 nm for high precision metrology
Henning Vahlbruch, Fabian Meylahn, Benno Willke
https://arxiv.org/abs/2508.10477

Characterization of non-planar ring oscillators at a wavelength of 1064 nm for high precision metrology
Ultra-stable laser light is essential for high-precision interferometric measurements, in particular for the next generation of gravitational wave detectors, where high power lasers with unprecedented low power and frequency noise are demanded. Since the seed laser for high-power laser system has a large influence on the overall noise characteristics, the use of the lowest noise seed laser is beneficial. This study compares a newly developed seed laser, based on a non-planar ring oscillator (NP…

Optical Fiber-Waveguide Hybrid Architecture for Mid-Infrared Ring Lasers
Tinghui An, T Toney Fernandez, Yuchen Wang, Yiguang Jiang, Benjamin Johnston, Solenn Cozic, Marcel Poulain, Thipahine Rault, Long Zhang, Alex Fuerbach
https://arxiv.org/abs/2509.03965

Optical Fiber-Waveguide Hybrid Architecture for Mid-Infrared Ring Lasers
We report a mid-infrared ring laser via fiber-to-waveguide hybrid integration enabled by directional couplers fabricated in fluoride glasses. Directional couplers were inscribed into fluoride glass using femtosecond laser direct writing, forming low-loss waveguides with a high positive refractive index change. The waveguides were optimized for efficient guidance at a wavelength of 2.7 {\textmu}m. Directional couplers with systematically varied coupling gap and interaction lengths were fabricate…

Narrow-linewidth, piezoelectrically tunable photonic integrated blue laser
Anat Siddharth, Asger B. Gardner, Xinru Ji, Shivaprasad U. Hulyal, Mikael S. Reichler, Alaina Attanasio, Johann Riemensberger, Sunil A. Bhave, Nicolas Volet, Simone Bianconi, Tobias J. Kippenberg
https://arxiv.org/abs/2508.02568…

Narrow-linewidth, piezoelectrically tunable photonic integrated blue laser
Frequency-agile lasers operating in the ultraviolet-to-blue spectral range (360-480 nm) are critical enablers for a wide range of technologies, including free-space and underwater optical communications, optical atomic clocks, and Rydberg-atom-based quantum computing platforms. Integrated photonic lasers offer a compelling platform for these applications by combining low-noise performance with fast frequency tuning in a compact, robust form factor through monolithic integration. However, realiz…

High-background X-ray single particle imaging enabled by holographic enhancement with 2D crystals
Abhishek Mall, Zhou Shen, Kartik Ayyer
https://arxiv.org/abs/2508.07953 https:/…

High-background X-ray single particle imaging enabled by holographic enhancement with 2D crystals
X-ray single particle imaging (SPI) has offered the potential to visualize structures of biomolecules at near-atomic resolution. However, state-of-the-art structures at X-ray free electron lasers (XFELs) are limited to moderate resolution, primarily due to background scattering. We computationally explore a modified SPI technique based on holographic enhancement from a strongly scattering 2D crystal lattice placed near the object. The Bragg peaks from the crystal enable structure retrieval even…

Theory of quantum spin-Hall topological lasers
Alberto Mu\~noz de las Heras, Iacopo Carusotto
https://arxiv.org/abs/2509.20920 https://arxiv.org/pdf/2509.2…

Theory of quantum spin-Hall topological lasers
We theoretically investigate a quantum spin-Hall topological laser formed by an array of dielectric ring resonators endowed of saturable gain. The system preserves time-reversal symmetry, the clockwise and counter-clockwise modes in each ring resonator acting as two pseudospin states that experience opposite synthetic magnetic fields. We consider ring resonators featuring an internal S-shaped waveguide asymmetrically coupling the two pseudospin states. In spite of the non-magnetic nature of the…

Nonlinear Photonic Neuromorphic Chips for Spiking Reinforcement Learning
Shuiying Xiang, Yonghang Chen, Haowen Zhao, Shangxuan Shi, Xintao Zeng, Yahui Zhang, Xingxing Guo, Yanan Han, Ye Tian, Yuechun Shi, Yue Hao
https://arxiv.org/abs/2508.06962

Nonlinear Photonic Neuromorphic Chips for Spiking Reinforcement Learning
Photonic computing chips have made significant progress in accelerating linear computations, but nonlinear computations are usually implemented in the digital domain, which introduces additional system latency and power consumption, and hinders the implementation of fully-functional photonic neural network chips. Here, we propose and fabricate a 16-channel programmable incoherent photonic neuromorphic computing chip by co-designing a simplified MZI mesh and distributed feedback lasers with satu…

How Does Incubation Affect Laser Material Processing?
Matthias Lenzner, J\"orn Bonse
https://arxiv.org/abs/2509.08326 https://arxiv.org/pdf/2509.08326…

How Does Incubation Affect Laser Material Processing?
In the last decades, the subject of laser-induced damage (LID) moved from a topic of scientific interest toward laser material processing for technical applications. When using pulsed lasers, the cumulative effect known as incubation is one of the most fundamental features of the processing event. Incubation manifests by the fact that the critical fluence for LID (known as laser-induced damage threshold, LIDT) depends on the number of pulses N exciting one spot on the sample. In most cases, the…

H\"ansch-Couillaud locking of a large Sagnac interferometer: advancing below the flicker floor
Jannik Zenner, Karl Ulrich Schreiber, Simon Stellmer
https://arxiv.org/abs/2510.08183

Hänsch-Couillaud locking of a large Sagnac interferometer: advancing below the flicker floor
Large Sagnac interferometers in the form of active ring lasers have emerged as unique rotation sensors in the geosciences, where their sensitivity allows to detect geodetic and seismological signals. The passive laser gyroscope variant, however, is still at a stage of development, and adequate laser frequency stabilization techniques are explored to reach the desired levels of sensitivity and stability. Here, we present the first Hänsch-Couillaud locked passive laser gyroscope. We employ a loc…

Passive harmonic mode-locked laser on lithium niobate integrated photonics
Yu Wang, Guanyu Han, Jan-Philipp Koester, Hans Wenzel, Wei Wang, Wenjun Deng, Ziyao Feng, Meng Tian, Andrea Al\`u, Andrea Knigge, Qiushi Guo
https://arxiv.org/abs/2510.03522

Passive harmonic mode-locked laser on lithium niobate integrated photonics
Mode-locked lasers (MLLs) are essential for a wide range of photonic applications, such as frequency metrology, biological imaging, and high-bandwidth coherent communications. The growing demand for compact and scalable photonic systems is driving the development of MLLs on various integrated photonics material platforms. Along these lines, developing MLLs on the emerging thin-film lithium niobate (TFLN) platform holds the promise to greatly broaden the application space of MLLs by harnessing T…

On-chip room-temperature CW lasing from a III-V nanowire integrated with a Si photonic crystal platform
Masato Takiguchi, Takuro Fujii, Hisashi Sumikura, Akihiko Shinya, Shinji Matsuo, Masaya Notomi
https://arxiv.org/abs/2510.05477

On-chip room-temperature CW lasing from a III-V nanowire integrated with a Si photonic crystal platform
We report the demonstration of continuous-wave (CW) lasing at room temperature from a III-V semiconductor nanowire integrated into a Si photonic crystal (PhC) cavity. Conventional hybrid nanowire lasers [M. Takiguchi. et.al., APL Photonics, 2, 046106 (2017)], which typically feature circular nanowire-cross-sections, suffer from a weak optical confinement, preventing CW lasing under ambient conditions. To overcome this limitation, we fabricated nanowires with rectangular cross-sections via dry e…

Extreme-ultraviolet laser generation at 118 nm via adaptive random additional periodic-phase engineering in a LiF crystal
Yanling Cheng, Bin Zhang, Fei Liang, Haohai Yu, Huaijin Zhang
https://arxiv.org/abs/2508.05412

Extreme-ultraviolet laser generation at 118 nm via adaptive random additional periodic-phase engineering in a LiF crystal
Extreme ultraviolet (EUV) coherent sources below 120nm are of paramount significance for promoting next-generation nano-scale lithography,precision spectroscopy, and exploring the emerging physical phenomena in quantum materials. Nonlinear optical conversion serves as the only feasible approach to obtain solid state EUV lasers, yet the intrinsic strong absorption at EUV and giant phase mismatch among light waves have hindered the realization of highly-efficient EUV light sources. Herein, we pro…

Unleashing HHG Efficiency: The Role of Driving Pulse Duration
Robert Klas, Martin Gebhardt, Jan Rothhardt, Jens Limpert
https://arxiv.org/abs/2510.04259 https://

Unleashing HHG Efficiency: The Role of Driving Pulse Duration
High harmonic generation (HHG) is a crucial technology for compact, high-brightness extreme ultraviolet (XUV) and soft X-ray sources, which are key to advancing both fundamental and applied sciences. The availability of advanced driving lasers, with tunable wavelength, power, and pulse duration, opens new opportunities for optimizing HHG-based sources. While scaling laws for wavelength are well understood, this work focuses on how pulse duration impacts HHG efficiency and introduces a unified f…

Self-cooling, blue-detuned dissipative Kerr microresonator soliton comb
Kenji Nishimoto, Kaoru Minoshima, Naoya Kuse
https://arxiv.org/abs/2508.00432 https://

Self-cooling, blue-detuned dissipative Kerr microresonator soliton comb
Dissipative Kerr solitons (DKSs) generated in high-Q microresonators driven by continuous-wave (CW) lasers provide chip-scale optical frequency combs composed of mutually coherent CW lines. However, their small mode volume makes them highly susceptible to thermal fluctuations, and the resulting thermo-refractive noise (TRN) perturbs the repetition rate $f_{\rm rep}$. Here, we experimentally demonstrate a blue-detuned DKS in a coupled-ring microresonator. By employing avoided-mode-crossing (AMX)…

Integrated broadband optical isolator via dynamic rotating destructive interference
Kyunghun Han, Yiliang Bao, Junyeob Song, David Long, Sean Bresler, Daron Westly, Jason Gorman, Thomas LeBrun, Kartik Srinivasan, Vladimir Aksyuk
https://arxiv.org/abs/2509.02866

Integrated broadband optical isolator via dynamic rotating destructive interference
Photonic integrated circuits route and shape light on a chip, but back-reflections feed back into coherent on-chip lasers, destabilizing operation and corrupting signals. Robust operation requires an integrated optical isolator that strongly suppresses backward propagation while maintaining low-loss, broadband forward transmission. However, prior on-chip isolators rely on magneto-optic materials or resonance-based filters, which respectively demand non-standard processes or inherently constrain…

Repetition-Rate-Difference Tunable Dual-Comb Fiber Laser Using Bidirectional Lyot filtering
Yuanjun Zhu, Bowen Liu, Maolin Dai, Yifan Ma, Shinji Yamashita, Takasumi Tanabe, Sze Yun Set
https://arxiv.org/abs/2509.01077

Repetition-Rate-Difference Tunable Dual-Comb Fiber Laser Using Bidirectional Lyot filtering
Single cavity dual-comb fiber lasers adopting different multiplexing configurations are benefited from the natures of common-mode noise suppression and superior coherence. Particularly, repetition-rate tunable dual-combs enable non-ambiguous ranging and aliasing-free spectroscopy. However, their sampling rate and spectral resolution is severely restricted by the mechanical delay lines. In a previous work, as rapid as 500 kHz/s tuning rate was realized to address this issue, while the minimum co…

Complex Band Structures and Bound States in the Continuum: A Unified Theoretical Framework
Jie Liu, Ziyun Peng, Qianju Song, Ang Chen, Liping Yang, Chunxiong Zheng, Dezhuan Han
https://arxiv.org/abs/2509.03163

Complex Band Structures and Bound States in the Continuum: A Unified Theoretical Framework
Complex band structures describe resonant modes in periodic systems finite in one direction, crucial for applications in photonics like sensors and lasers. The imaginary frequency component, $ω''$, tied to quality factors, is often probed through numerical or phenomenological models, limiting deeper insights. Here, we introduce a first-principles framework deriving complex band structures from scattering matrix poles, integrated with perturbation theory to define minimal Hilbert spaces based o…

Adaptive optics design for high-energy kW-class multi-slab laser amplifier
Tom\'a\v{s} Paliesek, Martin Divok\'y, Jan Pila\v{r}, Martin Smr\v{z}, Tom\'a\v{s} Mocek
https://arxiv.org/abs/2508.02259

Adaptive optics design for high-energy kW-class multi-slab laser amplifier
We demonstrate real-time wavefront correction in a high-energy high-average-power DiPOLE100/Bivoj laser using adaptive optics. A bimorph deformable mirror and Shack-Hartmann wavefront sensor reduced wavefront error tenfold and improved the Strehl ratio elevenfold. Design aspects such as deformable mirror actuator geometry, optimal placement, and loop frequency are discussed for integration into next-generation high-energy high-average-power lasers.

Transition from exceptional points to observable nonlinear bifurcation points in anti-PT symmetric coupled cavity systems
Takahiro Uemura, Kenta Takata, Masaya Notomi
https://arxiv.org/abs/2509.01062

Transition from exceptional points to observable nonlinear bifurcation points in anti-PT symmetric coupled cavity systems
Exceptional points (EPs) in anti-parity-time (APT)-symmetric systems have attracted significant interest. While linear APT-symmetric systems exhibit structural similarities with nonlinear dissipative systems, such as mutually injection-locked lasers, the correspondence between exceptional points in linear non-Hermitian Hamiltonians and bifurcation phenomena in nonlinear lasing dynamics has remained unclear. We demonstrated that, in a two-cavity system with APT symmetry and gain saturation nonli…

Universal Numerical Simulation Model for Laser Material Processing
Andreas Otto, Michele Buttazzoni, Carlos Dur\'an, Tobias Florian, Constantin Zenz
https://arxiv.org/abs/2509.22666

Universal Numerical Simulation Model for Laser Material Processing
High power lasers are used for a variety of manufacturing processes on time and length scales that cover many orders of magnitude and on different materials. The variety of processes achievable through laser-material interaction results from numerous coupled, nonlinear physical phenomena. Simulation models can be used to gain process understanding, explain experimentally observed phenomena, and optimize or design processes. However, the inherent complexity and diversity of the phenomena make mo…

Post-compression of a Q-switched laser in a glass-rod multi-pass cell
Peer Biesterfeld (Leibniz University Hannover, Institute of Quantum Optics, Welfengarten 1, Hannover, Germany), Arthur Sch\"onberg (Deutsches Elektronen-Synchrotron DESY, Notkestra{\ss}e 85, 22607 Hamburg, Germany), Marc Seitz (Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestra{\ss}e 85, Hamburg, Germany), Nayla Jimenez (Deutsches Elektronen-Synchrotron DESY, Notkestra{…

Post-compression of a Q-switched laser in a glass-rod multi-pass cell
Q-switched lasers are compact, cost-effective, and highly pulse energy-scalable sources for nanosecond-scale laser pulses. The technology has been developed for many decades and is widely used in scientific, industrial and medical applications. However, their inherently narrow bandwidth imposes a lower limit on pulse duration - typically in the few-hundred-picosecond range - limiting the applicability of Q-switched technology in fields that require ultrafast laser pulses in the few-picosecond o…

Electrically-pumped soliton microcombs on thin-film lithium niobate
Xiaomin Lv, Ze Wang, Tianyu Xu, Chen Yang, Xing Jin, Binbin Nie, Du Qian, Yanwu Liu, Kaixuan Zhu, Bo Ni, Qihuang Gong, Fang Bo, Qi-Fan Yang
https://arxiv.org/abs/2510.00371

Electrically-pumped soliton microcombs on thin-film lithium niobate
Thin-film lithium niobate (TFLN) has enabled efficient on-chip electro-optic modulation and frequency conversion for information processing and precision measurement. Extending these capabilities with optical frequency combs unlocks massively parallel operations and coherent optical-to-microwave transduction, which are achievable in TFLN microresonators via Kerr microcombs. However, fully integrated Kerr microcombs directly driven by semiconductor lasers remain elusive, which has delayed integr…

Large-Area Metal-Integrated Grating Electrode Achieving Near 100% Infrared Transmission
Karolina Bogdanowicz, Weronika Glowadzka, Tristan Smolka, Michal Rygala, Marcin Kaluza, Marek Ekielski, Oskar Sadowski, Magdalena Zadura, Magdalena Marciniak, Marcin Gebski, Michal Wasiak, Marcin Motyka, Anna Szerling, Tomasz Czyszanowski
https://arxiv.…

Large-Area Metal-Integrated Grating Electrode Achieving Near 100% Infrared Transmission
Highly transparent and conductive electrodes operating in the infrared (IR) are critically needed for a broad range of technologies, including light-emitting diodes, lasers and photodetectors, which are key building blocks of infrared cameras, LiDARs, and thermal systems such as IR heaters. While transparent conductive electrodes (TCEs) have seen substantial progress in the visible spectrum, their performance in the IR remains limited due to increased absorption and reflection caused by the pla…

Dichography: Two-frame Ultrafast Imaging from a Single Diffraction Pattern
Linos Hecht, Andre Al Haddad, Bj\"orn Bastian, Thomas M. Baumann, Johan Bielecki, Christoph Bostedt, Subhendu De, Alberto De Fanis, Simon Dold, Thomas Fennel, Fanny Goy, Christina Graf, Robert Hartmann, Georg Jakobs, Maximilian Joschko, Gregor Knopp, Katharina Kolatzki, Sivarama Krishnan, Bj\"orn Kruse, Asbj{\o}rn {\O}. L{\ae}gdsmand, Bruno Langbehn, Suddhasattwa Mandal, Tommaso Mazza, Michael Meyer, C…

Dichography: Two-frame Ultrafast Imaging from a Single Diffraction Pattern
X-ray free-electron lasers can nowadays deliver pairs of ultrabright, ultrashort light pulses with controllable delays at different photon energies. When combined with diffraction experiments, the interaction of these pulses with a sample at different times can produce two snapshots of an evolving system, enabling spatial and temporal resolution of ultrafast dynamics in nanomatter at and beyond the terahertz time scale. However, light detectors are orders of magnitude slower. The diffraction si…

Towards direct nonlinear compression of energetic sub-nanosecond pulses to the ultrafast regime
Gaspard Beaufort, Nayla Jimenez, Gunnar Arisholm, Victor Hariton, Ayhan Tajalli, Ingmar Hartl, Anne-Lise Viotti, Marcus Seidel
https://arxiv.org/abs/2507.20883

Towards direct nonlinear compression of energetic sub-nanosecond pulses to the ultrafast regime
Applications of terawatt-class lasers can enormously benefit from pulse trains with kHz repetition rates. The associated unprecedented combinations of peak and average powers require the development of new concepts for scalable ultrashort pulse generation. We propose using multi-mirror multi-pass cells as a compact and cost-efficient solution for the direct post-compression of sub-nanosecond pulses into the femtosecond regime. We simulate spectral broadening of 100-mJ, 300-ps pulses to a sub-ps…

Electro-optic frequency comb-empowered precise measurement of the dynamic frequency of a laser
Weiwei Yang, Xingyu Jia, Jingyi Wang, Xinlun Cai, Yang Li, Guanhao Wu
https://arxiv.org/abs/2508.16278

Electro-optic frequency comb-empowered precise measurement of the dynamic frequency of a laser
Frequency-modulated lasers (FMLs) are widely used in spectroscopy, biology, and LiDAR. The performance of these applications highly depends on the fast and precise tracking of the FMLs' absolute frequency, which remains a challenge. Here we demonstrate integrated lithium niobate electro-optic frequency combs with arbitrarily tunable repetition rates and a 29.45-nm bandwidth, enabling precise tracking of the absolute frequency of an FML with a chirp rate as high as $2\times10^{18}\,\mathrm{Hz/s}…

Wave morphing and flat-top ground states in photonics systems driven by artificial gauge fields
Peishen Li, Xiaoyu Zhang, Feifan Wang, Ye Chen, Xuefan Yin, Yuri Kivshar, Chao Peng
https://arxiv.org/abs/2509.21183

Wave morphing and flat-top ground states in photonics systems driven by artificial gauge fields
In quantum physics, classical optics, and many other wave systems, wave confinement in a potential well produces is associated with discrete oscillatory states, and the ground state is typically assumed to vanish uniformly. An open question is whether the ground state can counterintuitively support a flat-top, nonzero envelope, offering new opportunities for quantum emitters, optical antennas, and lasers. Here, we show that by applying the Byers-Yang theorem with an artificial gauge field, ener…

Noise-Induced Limits on Responsivity and SNR for Nonlinear Exceptional Point Sensing
Todd Darcie, J. Stewart Aitchison
https://arxiv.org/abs/2509.20346 https://

Noise-Induced Limits on Responsivity and SNR for Nonlinear Exceptional Point Sensing
Exceptional points (EPs) have been suggested for ultra-sensitive sensing because the eigenfrequency splitting grows as the nth-root of a perturbation, suggesting divergent responsivity. In ideal linear devices, however, this responsivity gain is reconciled by a matching divergence in the quantum shot-noise floor, so the net signal-to-noise ratio remains unchanged. Recent work has extended this argument to nonlinear devices, such as above-threshold lasers, predicting other divergences at an EP t…

Integrated Architecture for the Automated Generation and Coil Stabilization of a PZT-Enabled Microcomb
Mark W. Harrington, Steven M. Zhu, Rahul Chawlani, Kaikai Liu, Shuman Sun, Ruxuan Liu, Xu Yi, Daniel J. Blumenthal
https://arxiv.org/abs/2507.16979

Integrated Architecture for the Automated Generation and Coil Stabilization of a PZT-Enabled Microcomb
Silicon nitride Dissipative Kerr Soliton (DKS) microcombs have emerged as a future solution to bring metrological optical frequency comb capabilities into a photonic integrated platform with mass-scale fabrication benefits. Precision applications demand low comb line phase noise as well as high repetition rate stability, but current approaches to achieve this involve complex architectures, multiple lasers, and high-power components, which are challenging to integrate to the chip scale. To achie…