Tootfinder

Efficient and scalable inter-module switching for distributed quantum computing architectures
Kamil Bradler
https://arxiv.org/abs/2508.19088 https://arxiv.…

Efficient and scalable inter-module switching for distributed quantum computing architectures
Large-scale fault-tolerant quantum computers of the future will likely be modular by necessity or by design. Modularity is inevitable if the substrate cannot support the desired error-correction code due to its planar geometry or manufacturing constraints resulting in a limited number of logical qubits per module. Even if the computer is compact enough there may be functional requirements to distribute the quantum computation substrate over distant regions of varying scales. In both cases, matt…

A $Z_4$ Scotogenic Model with Higgs Portal
Noel Jonathan Jobu, Kenji Nishiwaki
https://arxiv.org/abs/2508.18713 https://arxiv.org/pdf/2508.18713

A $Z_4$ Scotogenic Model with Higgs Portal
We propose a new Scotogenic type model based on a global $Z_4$ symmetry involving dark matter candidates. After the symmetry breaking as $Z_4$ to $Z_2$ via the singlet scalar vacuum expectation value (VEV), the lightest Majorana fermion works as a viable thermal freeze-out dark matter (DM) candidate, and the mass terms for active neutrinos are generated as a finite quantum correction at the 1-loop level. A key point of realising our Scotogenic structure is to introduce two types of Majorana fer…

Optical Switching of Moir\'e Chern Ferromagnet
Xiangbin Cai, Haiyang Pan, Yuzhu Wang, Abdullah Rasmita, Shunshun Yang, Yan Zhao, Wei Wang, Ruihuan Duan, Ruihua He, Kenji Watanabe, Takashi Taniguchi, Zheng Liu, Jes\'us Z\'u\~niga P\'erez, Bo Yang, Weibo Gao
https://arxiv.org/abs/2508.19602

Optical Switching of Moiré Chern Ferromagnet
Optical manipulation of quantum matter offers a non-contact, high-precision and fast control. Fractional Chern ferromagnet states in moiré superlattices are promising for topological quantum computing, but an effective optical control protocol has remained elusive. Here, we demonstrate robust optical switching of integer and fractional Chern ferromagnets in twisted MoTe2 bilayers using circularly polarized light. Highly efficient optical manipulation of spin orientations in the topological fer…

Gain-Assisted and Dynamically Controlled Optical Bistability for Quantum Logic Gate Applications
Parkhi Bhardwaj, Poonam Yadav, Bodhaditya Santra, Shubhrangshu Dasgupta
https://arxiv.org/abs/2508.18332

Gain-Assisted and Dynamically Controlled Optical Bistability for Quantum Logic Gate Applications
The propagation of a probe field in an N-type four level cold atomic system is investigated under the influence of multiple coherent fields. Coherent control of quantum interference enables switching of the probe field between transparency and gain regimes. Subsequent analysis focuses on how the introduction of gain in the probe transition lowers the threshold for optical bistability, thereby enhancing the nonlinear response of the system at reduced input intensities. A detailed analysis of opt…

Optical control over topological Chern number in moir\'e materials
Olivier Huber, Kilian Kuhlbrodt, Eric Anderson, Weijie Li, Kenji Watanabe, Takashi Taniguchi, Martin Kroner, Xiaodong Xu, Atac Imamoglu, Tomasz Smolenski
https://arxiv.org/abs/2508.19063

Optical control over topological Chern number in moiré materials
Controlling quantum matter with light offers a promising route to dynamically tune its many-body properties, ranging from band topology to superconductivity. However, achieving such optical control for strongly correlated electron systems in the steady-state has remained elusive. Here, we demonstrate all-optical switching of the spin-valley degree of freedom of itinerant ferromagnets in twisted MoTe2 homobilayers. This system uniquely features flat valley-contrasting Chern bands and exhibits a …

Zero-energy resonances in ultracold hydrogen sticking to liquid helium films of finite thickness
R. Karahanyan, A. Voronin, V. Nesvizhevsky, A. Semakin, S. Vasiliev
https://arxiv.org/abs/2509.14652

Zero-energy resonances in ultracold hydrogen sticking to liquid helium films of finite thickness
We investigated quantum states of ultracold hydrogen atoms in a combined potential comprising the H-He film interaction in the presence of a substrate and the Earth gravitational field. We show that the shift and width of the gravitational quantum states are determined by the complex scattering length for the H-He film-substrate potential. We demonstrate that for specific helium film thicknesses above a substrate, zero-energy resonances occur if the combined potential supports a bound state exa…

Single-Shot Universality in Quantum LDPC Codes via Code-Switching
Shi Jie Samuel Tan, Yifan Hong, Ting-Chun Lin, Michael J. Gullans, Min-Hsiu Hsieh
https://arxiv.org/abs/2510.08552

Single-Shot Universality in Quantum LDPC Codes via Code-Switching
Code-switching is a powerful technique in quantum error correction that allows one to leverage the complementary strengths of different codes to achieve fault-tolerant universal quantum computation. However, existing code-switching protocols that encapsulate recent generalized lattice surgery approaches often either require many rounds of measurements to ensure fault-tolerance or suffer from low code rates. We present a single-shot, universal protocol that uses code-switching between high-rate …

Stacking-induced type-II quantum spin Hall insulators with high spin Chern number in unconventional magnetism
Chao-Yang Tan, Panjun Feng, Ze-Feng Gao, Fengjie Ma, Peng-Jie Guo, Zhong-Yi Lu
https://arxiv.org/abs/2508.05365

Stacking-induced type-II quantum spin Hall insulators with high spin Chern number in unconventional magnetism
Generally, stacking two monolayer type-I quantum spin Hall insulators gives rise to a trivial insulator. However, whether or not stacking two type-II quantum spin Hall insulators results in a trivial insulator has not yet been explored. In this letter, based on the calculations of lattice model, we demonstrate that stacking two type-II quantum spin Hall insulators does not yield a trivial insulator, but instead forms a quantum spin Hall insulator with high spin Chern number. In this phase, ther…

Cavity-based optical switching via phase modulation in warm rubidium vapor
Georgia Booton, Tabijah Wasawo, William O. C. Davis, Cameron McGarry, K. R. Rusimova, Alex O. C. Davis, Josh Nunn, Peter J. Mosley
https://arxiv.org/abs/2508.06255

Cavity-based optical switching via phase modulation in warm rubidium vapor
Optical switching remains a key outstanding challenge for scalable fault-tolerant photonic quantum computing due to the trade-off between speed, bandwidth, and loss. Scalable quantum photonics demands all three, to enable high computational clock rates and resource efficient scaling to large systems. We present a cavity-based optical switch that overcomes this limitation, demonstrating 22 ns rise time, insertion loss of 2.4 dB, and 17.5 dB extinction ratio. All-optical control is achieved via p…

A quantum computing approach to efficiently simulating correlated materials using impurity models and dynamical mean field theory
Norman Hogan, Efekan K\"okc\"u, Thomas Steckmann, Liam P. Doak, Carlos Mejuto-Zaera, Daan Camps, Roel Van Beeumen, Wibe A. de Jong, A. F. Kemper
https://arxiv.org/abs/2508.05738

A quantum computing approach to efficiently simulating correlated materials using impurity models and dynamical mean field theory
The accurate theoretical description of materials with strongly correlated electrons is a formidable challenge, at the forefront of condensed matter physics and computational chemistry alike, and it is one of the targets for quantum computing. Dynamical Mean Field Theory (DMFT) is a successful approach that predicts behaviors of such systems by incorporating some correlated behavior, but it is limited by the need to calculate the Green's function for the impurity model. This work proposes a fra…