Tootfinder

Noise-Robust Phase Connectivity Estimation via Bayesian Circular Functional Models
Shonosuke Sugasawa, Takeru Matsuda, Tomoyuki Nagakawa
https://arxiv.org/abs/2509.06418 https:/…

Noise-Robust Phase Connectivity Estimation via Bayesian Circular Functional Models
The phase locking value (PLV) is a widely used measure to detect phase connectivity. Main drawbacks of the standard PLV are it can be sensitive to noisy observations and does not provide uncertainty measures under finite samples. To overcome the difficulty, we propose a model-based PLV through nonparametric statistical modeling. Specifically, since the discrete time series of phase can be regarded as a functional observation taking values on circle, we employ a Bayesian model for circular-varia…

Multiscale phase oscillations induced by cluster synchronisation in human connectome core network
Bosiljka Tadic, Marija Mitrovic Dankulov, Roderick Melnik
https://arxiv.org/abs/2507.07583

Multiscale phase oscillations induced by cluster synchronisation in human connectome core network
Brain imaging data mapping onto human connectome networks enables the investigation of global brain dynamics, where the brain hubs play an essential role in transferring activity between different brain parts. At this scale, the synchronisation processes are increasingly investigated as one of the key mechanisms revealing many aspects of brain functional coherence in healthy brains and revealing deviations due to various brain disorders. For the human connectome core network, consisting of the …

Unconventional Materials for Light Dark Matter Detection
Yonit Hochberg, Dino Novko, Rotem Ovadia, Antonio Politano
https://arxiv.org/abs/2507.07164 https:…

Unconventional Materials for Light Dark Matter Detection
We propose the use of several unconventional materials as detectors for dark matter with mass beneath the MeV scale. These include the transition-metal dichalcogenide TiSe$_2$ hosting a low-energy plasmon in the charge-density-wave phase, Sr$_2$RuO$_4$ containing a low-energy acoustic demon mode, and hole-doped diamond with tunable optical and acoustic plasmon frequencies. We perform first-principles density functional theory computations of their loss functions at non-vanishing momenta and est…

Origin of insulating-like behavior of Bi$_2$Sr$_2$CaCu$_2$O$_{8 x}$ under pressure: A first-principles study
Xin Du, Jian-Feng Zhang, Zhong-Yi Lu, Kai Liu
https://arxiv.org/abs/2507.07336

Origin of insulating-like behavior of Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ under pressure: A first-principles study
Recent experimental study on Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ superconductors has revealed an unexpected quantum phase transition from superconducting state to insulatinglike state under pressure [Zhou et al., Nat. Phys. 18, 406 (2022)]. To better understand the physical origin of this pressure-induced phenomenon, here we have studied the structural, electronic, and magnetic properties of undoped and O-doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (Bi2212) under pressures based on density-functional theory …

Two-legged approximation for building non-empirical hybrids and analyzing correlation at finite temperature
Brittany P. Harding, Francisca Sagredo, Vincent Martinetto, Aurora Pribram-Jones
https://arxiv.org/abs/2509.07970

Two-legged approximation for building non-empirical hybrids and analyzing correlation at finite temperature
Warm dense matter is a highly energetic phase characterized by strong correlations, thermal effects, and quantum effects of electrons. Thermal density functional theory is commonly used in simulations of this challenging phase, driving the development of temperature-dependent approximations to the exchange-correlation free energy. In this work, a finite-temperature extension of the two-legged adiabatic connection construction is demonstrated for the uniform electron gas and asymmetric Hubbard d…

Enhanced spin-to-charge conversion in La$_{0.67}$Sr$_{0.33}$MnO$_3$/NdNiO$_3$ bilayers at the nickelate metal-insulator phase transition
Biswajit Sahoo, Sarmistha Das, Akilan K, Alexandre Pofelski, Sebastien Petit-Watelot, Juan-Carlos Rojas-S\'anchez, Yimei Zhu, Alex Frano, Eric E Fullerton
https://arxiv.org/abs/2508.05300

Enhanced spin-to-charge conversion in La$_{0.67}$Sr$_{0.33}$MnO$_3$/NdNiO$_3$ bilayers at the nickelate metal-insulator phase transition
Phase transition materials such as NdNiO3 (NNO) when coupled with low damping ferromagnets such as La$_{0.67}$Sr$_{0.33}$MnO$_3$ (LSMO) can lead to new multi-functional material systems harnessing the interplay of charge, spin and orbital degrees of freedom. In this study, we probe the evolution of the spin-to-charge conversion in epitaxial all-oxide LSMO (12 nm)/NNO (4, 8, and 16 nm) bilayers. Using spin pumping ferromagnetic resonance we track the spin-charge conversion in the NNO layer throu…

Functional renormalization group study of rho condensate at a finite isospin chemical potential in the quark meson model
Mohammed Osman, Defu Hou, Wentao Wang, Hui Zhang
https://arxiv.org/abs/2508.02745

Functional renormalization group study of rho condensate at a finite isospin chemical potential in the quark meson model
We investigate the effect of an isospin chemical potential ($μ_{I}$) within the quark-meson model, which approximates quantum chromodynamics (QCD) by modeling low energy phenomena such as chiral symmetry breaking and phase structure under varying conditions of temperature and chemical potential. Using the functional renormalization group (FRG) flow equations, we calculate the phase diagram in the chiral limit within the two-flavor quark-meson model in a finite $μ_{I}$ with $ρ$ vector meson i…

Ionization/dissociation-driven first order phase transitions: on a new class of first order phase transitions
Genri Norman, Ilnur Saitov
https://arxiv.org/abs/2509.01273 https:/…

Ionization/dissociation-driven first order phase transitions: on a new class of first order phase transitions
In this work, we compare various models for describing the phase transition of the fluid hydrogen into a conducting state, including both chemical models of plasma and first-principle simulations within the framework of the density functional theory (DFT). The comparison of the results indicates the plasma nature of the phase transition in warm dense hydrogen. We propose a concept of a new class of first-order phase transitions: ionization or dissociation-driven phase transitions, with which th…

The use of open boundaries in stochastic hydrodynamic models of nucleation
James F. Lutsko
https://arxiv.org/abs/2508.05528 https://arxiv.org/pdf/2508.0552…

The use of open boundaries in stochastic hydrodynamic models of nucleation
Stochastic hydrodynamics is a central tool in the study of first order phase transitions at a fundamental level. Combined with sophisticated free energy models, e.g. as developed in classical Density Functional Theory, complex processes such as crystallization can be modeled and information such as free energy barriers, nucleation pathways and the unstable eigenvector and eigenvalues determined. The latter are particularly interesting as they play key roles in defining the natural (unbiased) or…

Chirality transfer in lyotropic twist-bend nematics
Anna Ashkinazi, Hemani Chhabra, Anouar El Moumane, Maxime M. C. Tortora, Jonathan P. K. Doye
https://arxiv.org/abs/2508.03544

Chirality transfer in lyotropic twist-bend nematics
Using molecular simulations and classical density functional theory, we study the liquid-crystalline phase behaviour of a series of bent rod-like mesogens with a controlled degree of chirality introduced through a twist at the centre of the particle. In the achiral limit, isotropic, uniaxial nematic, twist-bend nematic and smectic phases form as the packing fraction increases. On introducing chirality, the symmetry between the right- and left-handed twist-bend phases is broken. The phase with t…

Doping Induced Magnetic and Electronic phase Transition in Ferrimagnetic Half-metallic Mn$_{4}$Al$_{11}$ Compound
Sujoy Datta, Prashant Singh
https://arxiv.org/abs/2507.05206

Doping Induced Magnetic and Electronic phase Transition in Ferrimagnetic Half-metallic Mn$_{4}$Al$_{11}$ Compound
The future of spintronic and semiconductor applications demands materials with tailored electronic and magnetic properties. This study uses density functional theory to investigate the electronic structure of the half-metallic compound Mn$_{4}$Al$_{11}$ under uniaxial strain and in its Ge-substituted derivatives. Strain analysis shows that although the half-metallic band-gap collapses under strain beyond $-2\%$, the ferrimagnetic character remains stable. Ge substitution at six inequivalent Al-…

An \textsf{AT1} phase-field framework for quasi-static anti-plane shear fracture: Unifying $\xi$-based adaptivity and nonlinear strain energy density function
Maria P. Fernando, S. M. Mallikarjunaiah
https://arxiv.org/abs/2506.23249

An \textsf{AT1} phase-field framework for quasi-static anti-plane shear fracture: Unifying $ξ$-based adaptivity and nonlinear strain energy density function
This work introduces a novel \textsf{AT1} phase-field framework for simulating quasi-static anti-plane shear fracture in geometrically linear elastic bodies. A key feature of this framework is the unification of $ξ$-based local mesh adaptivity -- where $ξ$ represents the characteristic length of the damage zone -- and an algebraically nonlinear strain energy density function. A modified Francfort-Marigo energy functional, together with its Ambrosio-Tortorelli-type regularization, is hereby pr…

Functional Renormalization for Signal Detection: Dimensional Analysis and Dimensional Phase Transition for Nearly Continuous Spectra Effective Field Theory
Riccardo Finotello, Vincent Lahoche, Dine Ousmane Samary
https://arxiv.org/abs/2507.01064

Functional Renormalization for Signal Detection: Dimensional Analysis and Dimensional Phase Transition for Nearly Continuous Spectra Effective Field Theory
Signal detection is one of the main challenges of data science. According to the nature of the data, the presence of noise may corrupt measurements and hinder the discovery of significant patterns. A wide range of techniques aiming at extracting the relevant degrees of freedom from data has been thus developed over the years. However, signal detection in almost continuous spectra, for small signal-to-noise ratios, remains a known difficult issue. This paper develops over recent advancements pro…

Flight-Ready Precise and Robust Carrier-Phase GNSS Navigation Software for Distributed Space Systems
Samuel Y. W. Low, Toby Bell, Simone D'Amico
https://arxiv.org/abs/2508.18246

Flight-Ready Precise and Robust Carrier-Phase GNSS Navigation Software for Distributed Space Systems
This paper presents the full requirements analysis, design, development, and testing of high-precision navigation flight software for Distributed Space Systems (DSS) using Carrier Phase Differential GNSS (CDGNSS). Five main contributions are made. First, a survey of flown and upcoming DSS missions with stringent precision requirements is conducted, from which a thorough requirements analysis is distilled to guide development and testing. Second, a real-time navigation functional architecture is…

From Generation to Adaptation: Comparing AI-Assisted Strategies in High School Programming Education
Tong Hu, Songzan Wang
https://arxiv.org/abs/2506.15955

From Generation to Adaptation: Comparing AI-Assisted Strategies in High School Programming Education
This exploratory case study investigated two contrasting pedagogical approaches for LCA-assisted programming with five novice high school students preparing for a WeChat Mini Program competition. In Phase 1, students used LCAs to generate code from abstract specifications (From-Scratch approach), achieving only 20% MVP completion. In Phase 2, students adapted existing Minimal Functional Units (MFUs), small, functional code examples, using LCAs, achieving 100% MVP completion. Analysis revealed t…

Gradient regularity for double-phase orthotropic functionals
Stefano Almi, Chiara Leone, Gianluigi Manzo
https://arxiv.org/abs/2507.18474 https://arxiv.org…

Gradient regularity for double-phase orthotropic functionals
We prove higher integrability for local minimizers of the double-phase orthotropic functional \[ \sum_{i=1}^{n}\int_Ω\left(\left|u_{x_i}\right|^p+a(x)\left| u_{x_i}\right|^q\right)dx \] when the weight function $a \geq0$ is assumed to be $α$-Hölder continuous, while the exponents $p, q$ are such that $2 \leq p \leq q$ and $\frac{q}{p} < 1 + \fracα{n}$. Under natural Sobolev regularity of~$a$, we further obtain explicit Lipschitz regularity estimates for local minimizer…

Thermoelectric Potential of NaVAs Half-Heusler Alloy: Insights from Ab-initio Calculations
Rajinder Singh, Shyam Lal Gupta, Sumit Kumar, Lalit Abhilashi, Diwaker, Ashwani Kumar
https://arxiv.org/abs/2509.05991

Thermoelectric Potential of NaVAs Half-Heusler Alloy: Insights from Ab-initio Calculations
This work presents a comprehensive investigation of the HH alloy NaVAs using first - principles methods, emphasizing its potential applications in various fields, including spintronics, thermoelectrics, and optoelectronics. We utilized density functional theory (DFT) within the full-potential linearized augmented plane wave (FLAPW) framework. Structural optimizations indicate that the alloy stabilizes in the ferromagnetic phase. Both mechanical and dynamical stability have been confirmed throug…

A variationally consistent and asymptotically convergent phase-field model for solute precipitation and dissolution
Andrea Lamperti, Laura De Lorenzis
https://arxiv.org/abs/2507.13270

A variationally consistent and asymptotically convergent phase-field model for solute precipitation and dissolution
We propose a novel phase-field model for solute precipitation and dissolution in liquid solutions. Unlike in previous studies with similar scope, in our model the two non-linear coupled governing equations of the problem, which deliver the solute ion concentration and the phase-field variable, are derived in a variationally consistent way starting from a free energy functional of Modica-Mortola type. The phase-field variable is assumed to follow the non-conservative Allen-Cahn evolution law, wh…

The effect of droplet configurations within the Functional Renormalization Group of low-dimensional Ising models
Ivan Balog, Lucija Nora Farka\v{s}, Maroje Marohni\'c, Gilles Tarjus
https://arxiv.org/abs/2506.23415

The effect of droplet configurations within the Functional Renormalization Group of low-dimensional Ising models
We explore the application of the nonperturbative functional renormalization group (NPFRG) within its most common approximation scheme based on truncations of the derivative expansion to the $Z_2$-symmetric scalar $φ^4$ theory as the lower critical dimension $d_{\rm lc}$ is approached. We aim to assess whether the NPFRG - a broad, nonspecialized method which is accurate in $d\geq 2$ - can capture the effect of the localized (droplet) excitations that drive the disappearance of the phase transi…

RIROS: A Parallel RTL Fault SImulation FRamework with TwO-Dimensional Parallelism and Unified Schedule
Jiaping Tang, Jianan Mu, Zizhen Liu, Ge Yu, Tenghui Hua, Bin Sun, Silin Liu, Jing Ye, Huawei Li
https://arxiv.org/abs/2508.16376

RIROS: A Parallel RTL Fault SImulation FRamework with TwO-Dimensional Parallelism and Unified Schedule
With the rapid development of safety-critical applications such as autonomous driving and embodied intelligence, the functional safety of the corresponding electronic chips becomes more critical. Ensuring chip functional safety requires performing a large number of time-consuming RTL fault simulations during the design phase, significantly increasing the verification cycle. To meet time-to-market demands while ensuring thorough chip verification, parallel acceleration of RTL fault simulation is…

Unconventional Materials for Light Dark Matter Detection
Yonit Hochberg, Dino Novko, Rotem Ovadia, Antonio Politano
https://arxiv.org/abs/2507.07164 https://

Unconventional Materials for Light Dark Matter Detection
We propose the use of several unconventional materials as detectors for dark matter with mass beneath the MeV scale. These include the transition-metal dichalcogenide TiSe$_2$ hosting a low-energy plasmon in the charge-density-wave phase, Sr$_2$RuO$_4$ containing a low-energy acoustic demon mode, and hole-doped diamond with tunable optical and acoustic plasmon frequencies. We perform first-principles density functional theory computations of their loss functions at non-vanishing momenta and est…

From trigonal to triclinic: Symmetry-tuned Rashba effects in buckled honeycomb SrHfO$_{3}$-based heterostructures
Okan K\"oksal
https://arxiv.org/abs/2508.01967 https://

From trigonal to triclinic: Symmetry-tuned Rashba effects in buckled honeycomb SrHfO$_{3}$-based heterostructures
Harnessing the interplay of symmetry breaking and spin-orbit coupling, we investigate Rashba spin splitting in buckled honeycomb (SrHfO$_3$)$_2$/(LaAlO$_3$)$_4$(111) superlattices using density functional theory (DFT) calculations with a Hubbard $U$ term and a Wannier-based tight-binding (TB) model. In the non-centrosymmetric $P1$ phase, pronounced Rashba-type splitting emerges near the $M$ and $K$ points accompanied by a helical in-plane spin texture, while the centrosymmetric $P321$ phase rem…

Multi-timescale frequency-phase matching for high-yield nonlinear photonics
Mahmoud Jalali Mehrabad, Lida Xu, Gregory Moille, Christopher J. Flower, Supratik Sarkar, Apurva Padhye, Shao-Chien Ou, Daniel G. Suarez-Forero, Mahdi Ghafariasl, Yanne Chembo, Kartik Srinivasan, Mohammad Hafezi
https://arxiv.org/abs/2506.15016

Multi-timescale frequency-phase matching for high-yield nonlinear photonics
Integrated nonlinear photonic technologies, even with state-of-the-art fabrication with only a few nanometer geometry variations, face significant challenges in achieving wafer-scale yield of functional devices. A core limitation lies in the fundamental constraints of energy and momentum conservation laws. Imposed by these laws, nonlinear processes are subject to stringent frequency and phase matching (FPM) conditions that cannot be satisfied across a full wafer without requiring a combination …

Exploring PdCrAs Half-Heusler Alloy for Sustainable Energy Solutions: An Ab-initio Study
Rajinder Singh, Shyam Lal Gupta, Sumit Kumar, Lalit Abhilashi, Diwaker, Ashwani Kumar
https://arxiv.org/abs/2509.05987

Exploring PdCrAs Half-Heusler Alloy for Sustainable Energy Solutions: An Ab-initio Study
This work presents a comprehensive investigation of the HH alloy PdCrAs using first - principles methods, highlighting its potential applications in various fields, including spintronics, thermoelectrics, and optoelectronics. We employed density functional theory (DFT) within the full potential linearized augmented plane wave (FLAPW) framework. Structural optimizations indicate that the alloy stabilizes in the ferromagnetic phase. Both mechanical and dynamical stability have been confirmed thro…

Addressing Phase Discrepancies in Functional Data: A Bayesian Approach for Accurate Alignment and Smoothing
Jacopo Gardella, Raffaele Argiento, Alessandro Casa, Alessia Pini
https://arxiv.org/abs/2506.14650

Addressing Phase Discrepancies in Functional Data: A Bayesian Approach for Accurate Alignment and Smoothing
In many real-world applications, functional data exhibit considerable variability in both amplitude and phase. This is especially true in biomechanical data such as the knee flexion angle dataset motivating our work, where timing differences across curves can obscure meaningful comparisons. Curves of this study also exhibit substantial variability from one another. These pronounced differences make the dataset particularly challenging to align properly without distorting or losing some of the i…

Real-time deep learning phase imaging flow cytometer reveals blood cell aggregate biomarkers for haematology diagnostics
Kerem Delikoyun, Qianyu Chen, Liu Wei, Si Ko Myo, Johannes Krell, Martin Schlegel, Win Sen Kuan, John Tshon Yit Soong, Gerhard Schneider, Clarissa Prazeres da Costa, Percy A. Knolle, Laurent Renia, Matthew Edward Cove, Hwee Kuan Lee, Klaus Diepold, Oliver Hayden

Real-time deep learning phase imaging flow cytometer reveals blood cell aggregate biomarkers for haematology diagnostics
While analysing rare blood cell aggregates remains challenging in automated haematology, they could markedly advance label-free functional diagnostics. Conventional flow cytometers efficiently perform cell counting with leukocyte differentials but fail to identify aggregates with flagged results, requiring manual reviews. Quantitative phase imaging flow cytometry captures detailed aggregate morphologies, but clinical use is hampered by massive data storage and offline processing. Incorporating …

Anomaly freedom in effective Loop Quantum Cosmology refined: extended functional dependence of the counter-terms
Maxime De Sousa, Aur\'elien Barrau, Killian Martineau
https://arxiv.org/abs/2506.14308

Anomaly freedom in effective Loop Quantum Cosmology refined: extended functional dependence of the counter-terms
Instead of assuming that they depend only on the background variables, we investigate the hypothesis that counter-terms appearing in the deformed algebra approach to loop quantum cosmology depend on the full phase-space variables. We derive the associated anomalies and solve the entire system in several specific cases. New restrictions on the generalized holonomy corrections are obtained.

Molecular Control of Floquet Topological Phase in Non-adiabatic Thouless Pumping
Ruiyi Zhou, Yosuke Kanai
https://arxiv.org/abs/2506.12147 https://

Molecular Control of Floquet Topological Phase in Non-adiabatic Thouless Pumping
Nonadiabatic Thouless pumping of electrons is studied in the framework of topological Floquet engineering, particularly focused on how changes to chemical moieties can control the emergence of the Floquet topological phase. We employ real-time time-dependent density functional theory to investigate the extent to which the topological invariant, the winding number, is impacted by molecular-level changes to trans-polyacetylene. In particular, several substitutions to trans-polyacetylene are studi…

Nuclear $\beta$-decay half-lives within the subtracted second random-phase approximation
Danilo Gambacurta, Marcella Grasso
https://arxiv.org/abs/2506.18849

Nuclear $β$-decay half-lives within the subtracted second random-phase approximation
We employ, within the framework of Skyrme energy-density functional theory, the subtracted second random-phase approximation, recently developed for charge-exchange excitations, to compute $β$-decay half-lives in four nuclei, $^{24}$O, $^{34}$Si, $^{78}$Ni, and $^{132}$Sn. Following our recent results on the description of the Gamow-Teller strength, we proceed coherently in the present work by computing $β$-decay half-lives using the bare value of the axial-vector coupling constant $g_A$. Hal…

A Non-Local Orientation Field Phase-Field Model for Misorientation- and Inclination- Dependent Grain Boundaries
Xiao Han, Axel van de Walle
https://arxiv.org/abs/2508.01688 http…

A Non-Local Orientation Field Phase-Field Model for Misorientation- and Inclination- Dependent Grain Boundaries
We propose to incorporate grain boundary (GB) anisotropy in phase-field modeling by extending the standard partial differential equations formulation to include a non-local functional of an orientation field. Regardless of the number of grains in the simulation, the model uses a single orientation field and incorporates grain misorientation and inclination information obtained from sampling the orientation field at optimized locations in the vicinity of the grain boundary. The formalism enables…

Joint Active and Passive Beamforming for Energy-Efficient STARS with Quantization and Element Selection in ISAC Systems
Li-Hsiang Shen, Yi-Hsuan Chiu
https://arxiv.org/abs/2507.16210

Joint Active and Passive Beamforming for Energy-Efficient STARS with Quantization and Element Selection in ISAC Systems
This paper investigates a simultaneously transmitting and reflecting reconfigurable intelligent surface (STARS)-aided integrated sensing and communication (ISAC) systems in support of full-space energy-efficient data transmissions and target sensing. We formulate an energy efficiency (EE) maximization problem jointly optimizing dual-functional radar-communication (DFRC)-empowered base station (BS) ISAC beamforming and STARS configurations of amplitudes, phase-shifts, quantization levels as well…

The equation of state and surface tension of QCD in the first order phase transition region
Yuan-jun Mei, Yi Lu, Fei Gao, Yu-xin Liu
https://arxiv.org/abs/2507.13697

The equation of state and surface tension of QCD in the first order phase transition region
We build up a complete description of QCD phase structure by applying the parametrization of the chiral and deconfinement order parameters upon the calculations from functional QCD approaches. In particular in the first order phase transition region at high chemical potential, both the phase transition line using Maxwell construction and the coexistence boundary lines from the spinodal decompostion are determined. We compute the thermodynamic quantities including the number density, the energy …

Learning the bulk and interfacial physics of liquid-liquid phase separation
Silas Robitschko, Florian Samm\"uller, Matthias Schmidt, Robert Evans
https://arxiv.org/abs/2507.08395

Learning the bulk and interfacial physics of liquid-liquid phase separation
We use simulation-based supervised machine learning and classical density functional theory to investigate bulk and interfacial phenomena associated with phase coexistence in binary mixtures. For a prototypical symmetrical Lennard-Jones mixture our trained neural density functional yields accurate liquid-liquid and liquid-vapour binodals together with predictions for the variation of the associated interfacial tensions across the entire fluid phase diagram. From the latter we determine the cont…

Stabilization of Ferroelectric Hafnia and Zirconia through Y2O3 doping
Li Yin, Cong Liu, R. E. Cohen
https://arxiv.org/abs/2509.00393 https://arxiv.org/pdf…

Stabilization of Ferroelectric Hafnia and Zirconia through Y2O3 doping
We investigate the possible stabilization of ferroelectricity in bulk Y2O3-doped hafnia and zirconia. We use density functional theory (DFT) with large random supercells of hafnia and zirconia and study the relative phase stability of the centrosymmetric cubic and monoclinic phases compared with the polar orthorhombic phase. We find that Y2O3-doping stabilizes the polar ferroelectric phase over the monoclinic baddeleyite phase in both hafnia and zirconia.

Multi-Gap superconductivity in HgS under pressure
Pietro Maria Forcella, Cesare Tresca, Antonio Sanna, Gianni Profeta
https://arxiv.org/abs/2507.21869 https://

Multi-Gap superconductivity in HgS under pressure
Mercury chalcogenides are a class of materials that exhibit diverse structural phases under pressure, leading to a range of exotic physical properties, including topological phases and chiral phonons. In particular, the phase diagram of mercury sulfide (HgS) remains difficult to characterize, with significant uncertainty surrounding the transition pressure between phases. Based on recent experimental results, we employ Density Functional Theory and Superconducting Density Functional Theory to i…

Weighted nonlocal area functionals without the triangle inequality
Serena Dipierro, Enrico Valdinoci, Mary Vaughan
https://arxiv.org/abs/2506.19048 https:/…

Weighted nonlocal area functionals without the triangle inequality
We consider a weighted nonlocal area functional in which the coefficients do not satisfy the triangle inequality. In the context of three phase transitions, this means that one of the weights is larger than the sum of the other two, say $$σ_{-1,1} > σ_{-1,0} + σ_{0,1}.$$ We show that the energy can be reduced by covering interfaces between phases $-1$ and $1$ with a thin strip of phase $0$. Moreover, as the fractional parameter $s\nearrow1$, we prove that the nonlocal energies $Γ$-converg…

From Density Functional Theory to Spin Hamiltonians: Magnetism in $d^5$ Honeycomb Compound OsCl$_3$
Ritwik Das, Indra Dasgupta
https://arxiv.org/abs/2506.22279

From Density Functional Theory to Spin Hamiltonians: Magnetism in $d^5$ Honeycomb Compound OsCl$_3$
Magnetism in strongly correlated honeycomb systems with $d^5$ electronic configuration has garnered significant attention due to its potential to realize the Kitaev spin liquid state, characterized by exotic properties. However, real materials exhibit not only Kitaev exchange interactions but also other magnetic exchanges, which may drive the transition from a spin liquid phase to a long-range ordered ground state. This work focuses on modelling the effective spin Hamiltonian for two-dimensiona…

Protocol for Clustering 4DSTEM Data for Phase Differentiation in Glasses
Mridul Kumar, Yevgeny Rakita
https://arxiv.org/abs/2509.00943 https://arxiv.org/pd…

Protocol for Clustering 4DSTEM Data for Phase Differentiation in Glasses
Phase-change materials (PCMs) such as Ge-Sb-Te alloys are widely used in non-volatile memory applications due to their rapid and reversible switching between amorphous and crystalline states. However, their functional properties are strongly governed by nanoscale variations in composition and structure, which are challenging to resolve using conventional techniques. Here, we apply unsupervised machine learning to 4-dimensional scanning transmission electron microscopy (4D-STEM) data to identify…

Observation of Altermagnetic Spin Splitting in an Intercalated Transition Metal Dichalcogenide
Milo Sprague, Mazharul Islam Mondal, Anup Pradhan Sakhya, Resham Babu Regmi, Surasree Sadhukhan, Arun K. Kumay, Himanshu Sheokand, Igor I. Mazin, Nirmal J. Ghimire, Madhab Neupane
https://arxiv.org/abs/2508.12985

Observation of Altermagnetic Spin Splitting in an Intercalated Transition Metal Dichalcogenide
Altermagnetism is a novel magnetic phase combining characteristics of both antiferromagnetism and ferromagnetic ordering. Despite growing theoretical interest in altermagnetic materials, reports of experimentally verified high Neel temperature layered compounds are limited or remain to be firmly established. Here, we present an angle resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) study of Co1/4TaSe2, a compound we identify as a layered altermagnetic material. Ma…

Metriplectic bracket for guiding-center Vlasov-Maxwell-Landau theory
A. J. Brizard, H. Sugama
https://arxiv.org/abs/2506.22289 https://

Metriplectic bracket for guiding-center Vlasov-Maxwell-Landau theory
The metriplectic formulation of collisional guiding-center Vlasov-Maxwell-Landau theory is presented. The guiding-center Landau collision operator, which describes collisions involving test-particle and field-particle guiding-center orbits, is represented in terms of a symmetric dissipative bracket involving functional derivatives of the guiding-center Vlasov phase-space density $F_{\rm gc}$ and the electromagnetic fields $({\bf D}_{\rm gc},{\bf B})$, where the guiding-center displacement vecto…

Axially Deformed Proton-Neutron Relativistic Quasiparticle Finite Amplitude Method for Charge-Exchange Transitions
Chen Chen, Zhengzheng Li, Yinu Zhang, Yifei Niu
https://arxiv.org/abs/2509.02110

Axially Deformed Proton-Neutron Relativistic Quasiparticle Finite Amplitude Method for Charge-Exchange Transitions
The quasiparticle finite amplitude method (QFAM) is extended to describe charge-exchange transitions based on the relativistic Hartree-Bogoliubov model, adopting the point-coupling energy density functional DD-PC1 and a finite-range separable pairing force. After validation through comparison with relativistic quasiparticle random-phase approximation (QRPA) results in spherical nuclei, the deformation effects on isobaric analog resonances (IAR) and Gamow-Teller (GT) transitions in Zn isotopes a…

Odd-Parity Magnetism in Fe-Based Superconductors
Reuel Dsouza, Andreas Kreisel, Brian M. Andersen, Daniel F. Agterberg, Morten H. Christensen
https://arxiv.org/abs/2508.21673 ht…

Odd-Parity Magnetism in Fe-Based Superconductors
Odd-parity magnetism constitutes an intriguing phase of matter which breaks inversion symmetry while preserving time-reversal symmetry. Here we demonstrate that the Fe-based superconductors exhibiting coplanar magnetic order realize an odd-parity magnetic state by combining low-energy modeling with density-functional theory. In the absence of spin-orbit coupling, the electronic spins are polarized along the $k_z$-direction and the splitting of the up and down states exhibits an $h$-wave form-fa…

On the adsorption of oxygen to high entropy alloy surfaces up to 2ML coverage using Density Functional Theory and Monte Carlo calculations
Tyler D. Dole\v{z}al, Adib J. Samin
https://arxiv.org/abs/2507.20084

On the adsorption of oxygen to high entropy alloy surfaces up to 2ML coverage using Density Functional Theory and Monte Carlo calculations
To enhance our understanding of oxidation in high-entropy alloys, the early stages of oxidation on the surface of Al10Nb15Ta5Ti30Zr40 were studied using density functional theory and thermodynamic modeling. Surface slabs were generated from bulk configurations sampled from equilibrium using a multicell Monte Carlo method for phase prediction. The bulk structure was found to be a single BCC phase in good agreement with experimental observations. The oxygen adsorbed with a strong preference for s…

Phonon Dynamics of Topological Quantum Materials
Vivek Kumar
https://arxiv.org/abs/2507.17203 https://arxiv.org/pdf/2507.17203

Phonon Dynamics of Topological Quantum Materials
The thesis presents a comprehensive Raman spectroscopic and first-principle density functional theory based investigation of V_(1-x)PS_(3) ; PbTaSe_(2) and 1T-TaS_(2). In V_(1-x)PS_(3),the detection of fractionalized excitations (Majorana fermions) suggests a potential Kitaev spin liquid phase, which becomes more pronounced as dimensionality decreases. Evidence of temperature-driven structural phase transition and topological surface phonons has been detected in PbTaSe_(2). TaS_(2) in 1T-phase …

$\Gamma$-convergence for nonlocal phase transitions involving the $H^{1/2}$ norm
Tim Heilmann
https://arxiv.org/abs/2507.11054 https://

$Γ$-convergence for nonlocal phase transitions involving the $H^{1/2}$ norm
We study functionals \begin{equation*} F_\varepsilon (u) := λ_\varepsilon \int_ΩW(u) \, dx + \varepsilon \|u\|_{H^{1/2}}^2 \end{equation*} for a double well potential $W$ and the Gagliardo seminorm $\|\cdot\|_{H^{1/2}}$ when $\varepsilon \ln(λ_\varepsilon) \rightarrow k$ as $\varepsilon \rightarrow 0^+$ and show compactness in the space of $BV$ functions on $Ω$ and the $Γ$-convergence to the classical surface tension functional.

The CP2K Program Package Made Simple
Marcella Iannuzzi, Jan Wilhelm, Frederick Stein, Augustin Bussy, Hossam Elgabarty, Dorothea Golze, Anna Hehn, Maximilian Graml, Stepan Marek, Beliz Sertcan G\"okmen, Christoph Schran, Harald Forbert, Rustam Z. Khaliullin, Anton Kozhevnikov, Mathieu Taillefumier, Rocco Meli, Vladimir Rybkin, Martin Brehm, Robert Schade, Ole Sch\"utt, Johann V. Pototschnig, Hossein Mirhosseini, Andreas Kn\"upfer, Dominik Marx, Matthias Krack, J\"ur…

The CP2K Program Package Made Simple
CP2K is a versatile open-source software package for simulations across a wide range of atomistic systems, from isolated molecules in the gas phase to low-dimensional functional materials and interfaces, as well as highly symmetric crystalline solids, disordered amorphous glasses, and weakly interacting soft-matter systems in the liquid state and in solution. This review highlights CP2K's capabilities for computing both static and dynamical properties using quantum-mechanical and classical simu…

Machine Learning Potentials for Alloys: A Detailed Workflow to Predict Phase Diagrams and Benchmark Accuracy
Siya Zhu, Doguhan Sariturk, Raymundo Arroyave
https://arxiv.org/abs/2506.16771

Machine Learning Potentials for Alloys: A Detailed Workflow to Predict Phase Diagrams and Benchmark Accuracy
High-entropy alloys (HEAs) have attracted increasing attention due to their unique structural and functional properties. In the study of HEAs, thermodynamic properties and phase stability play a crucial role, making phase diagram calculations significantly important. However, phase diagram calculations with conventional CALPHAD assessments based on experimental or ab-initio data can be expensive. With the emergence of machine-learning interatomic potentials (MLIPs), we have developed a program …

Mott transition from the non-analyticity of the one-body reduced density-matrix functional
Zhengqian Cheng, Chris A. Marianetti
https://arxiv.org/abs/2508.14110 https://

Mott transition from the non-analyticity of the one-body reduced density-matrix functional
One-body reduced density-matrix functional (1RDMF) theory has yielded promising results for small systems such as molecules, but has not addressed quantum phase transitions such as the Mott transition. Here we explicitly execute the constrained search within a variational ansatz to construct a 1RDMF for the multi-orbital Hubbard model with up to seven orbitals in the thermodynamic limit. The variational ansatz is the \mathcal{N}=3 ansatz of the variational discrete action theory (VDAT), which c…

Superconducting Diode Effect in Weak Localization Regime
Naratip Nunchot, Youichi Yanase
https://arxiv.org/abs/2507.21897 https://arxiv.org/pdf/2507.21897

Superconducting Diode Effect in Weak Localization Regime
We study a dirty two-dimensional superconductor with Rashba spin-orbit coupling and in-plane Zeeman fields described by the nonlinear sigma model that includes short-range electron-electron interactions from the Coulomb and Cooper channels. The renormalized Ginzburg-Landau theory, which includes the weak localization effects at the one-loop level, is constructed by using the Keldysh functional formalism. It is shown that the tricritical point appears in the phase diagram. The superconducting di…

Towards construction of microscopic model for smart coating of a solid surface
O. Pizio
https://arxiv.org/abs/2506.14628 https://arxi…

Towards construction of microscopic model for smart coating of a solid surface
The density functional approach for classical associating fluids is used to explore the wetting phase diagrams for model systems consisting of water and graphite-like solid surfaces chemically modified by a small amount of grafted chain molecules. The water-like fluid model is adopted from the work of Clark et al. [Mol. Phys., 104, 3561 (2006)]. It very well describes the bulk water vapor-liquid coexistence. Each chain molecule consists of tangentially bonded hard sphere segments. We focus on t…

Phonon spectrum in the spin-Peierls phase of CuGeO$_3$
L. Spitz, A. Razpopov, S. Biswas, H. Lane, S. E. Nikitin, K. Iida, R. Kajimoto, M. Fujita, M. Arai, M. Mourigal, Ch. R\"uegg, R. Valent\'i, B. Normand
https://arxiv.org/abs/2507.12409

Phonon spectrum in the spin-Peierls phase of CuGeO$_3$
CuGeO$_3$ has long been studied as a prototypical example of the spin-Peierls transition in a $S = 1/2$ Heisenberg chain. Despite intensive investigation of this quasi-one-dimensional material, systematic measurements and calculations of the phonon excitations in the dimerized phase have not to date been possible, leaving certain aspects of the spin-Peierls phenomenon unresolved. We perform state-of-the-art density functional theory (DFT) calculations to compute the electronic structure and pho…

Quantum Anharmonic Effects in Hydrogen-Bond Symmetrization of High-Pressure Ice
Qi Zhang, Lei Wang
https://arxiv.org/abs/2507.01452 https://

Quantum Anharmonic Effects in Hydrogen-Bond Symmetrization of High-Pressure Ice
The nuclear quantum effects of hydrogen play a significant role in determining the phase stability of water ice. Hydrogen-bond symmetrization occurs as hydrogen atoms tunnel in a double-well potential, ultimately occupying the midpoint between oxygen atoms and transforming ice VIII into ice X under high pressure. Quantum fluctuations lower this transition from classical predictions of over 100 GPa to 60 GPa. We reveal that the Perdew-Burke-Ernzerhof functional underestimates the hydrogen double…

QED-IR as Topological Quantum Theory of Dressed States
J. Gamboa, F. Mendez
https://arxiv.org/abs/2507.11668 https://arxiv.org/pdf/25…

QED-IR as Topological Quantum Theory of Dressed States
We investigate quantum electrodynamics in the infrared regime (QED-IR) using the adiabatic approximation and the framework of the functional Berry phase. In this approach, the physical state space is exact, nonperturbatively dressed, and endowed with a topological structure. Electrons do not exist as bare particles, but as topologically protected electron-photon clouds, defining a new kind of infrared quantum. These clouds are weakly bound in energy -- with a binding scale estimated at \( Λ_{\…

A min-max variational approach to the existence of gravity water waves
Dennis Kriventsov, Georg S. Weiss
https://arxiv.org/abs/2508.12159 https://arxiv.org…

A min-max variational approach to the existence of gravity water waves
We establish the existence of gravity water waves by applying a mountain pass theorem to a singular perturbation of the Alt-Caffarelli functional associated with the two-dimensional water wave equations. Our approach is formulated entirely in physical coordinates and does not require the air phase to be connected, nor does it rely on symmetry or monotonicity in the $x$ or $y$ directions. The framework presented allows for both a variational approach to a variety of fluid equilibrium problems an…

Understanding high photocatalytic activity of the TiO2 high-pressure columbite phase by experiments and first-principles calculations
Jacqueline Hidalgo-Jimenez, Taner Akbay, Tatsumi Ishihara, Kaveh Edalati
https://arxiv.org/abs/2508.12559

Understanding high photocatalytic activity of the TiO2 high-pressure columbite phase by experiments and first-principles calculations
The clean production of hydrogen as a zero-emission fuel can be done using photocatalysis, with TiO2 being one of the most promising photocatalysts. However, the activity of TiO2 anatase and rutile phases is still limited. In this study, an oxygen-deficient high-pressure phase of TiO2, columbite, is stabilized by a high-pressure torsion method. The phase is utilized as an active photocatalyst for hydrogen production, and the mechanism of its high activity is examined using density functional th…

Gapless superfluidity in neutron stars: Normal-fluid fraction
Valentin Allard, Nicolas Chamel
https://arxiv.org/abs/2506.10649 https://

Gapless superfluidity in neutron stars: Normal-fluid fraction
Our previous investigation within the time-dependent nuclear energy-density functional theory showed that the nuclear superfluids contained inside cold neutron stars could become gapless under certain circumstances. The absence of a gap in the energy spectrum of quasiparticle excitations leads to a specific heat that is comparable to that in the normal phase in sharp contrast with the exponential suppression in the BCS phase of type $^1S_0$ pairing. Here, we further study gapless superfluidity …

Evaluating Moment Tensor Potential in Ag-Cu Alloy: Accuracy, Transferability, and Phase Diagram Fidelity
Mashroor S. Nitol, Marco J. Echeverr\'ia Iriarte, Doyl E. Dickel, Saryu J. Fensin
https://arxiv.org/abs/2508.18129

Evaluating Moment Tensor Potential in Ag-Cu Alloy: Accuracy, Transferability, and Phase Diagram Fidelity
A Moment Tensor Potential (MTP) has been developed for the Cu-Ag binary alloy and its accuracy, transferability, and thermodynamic fidelity evaluated. The model was trained on a diverse dataset encompassing solid, liquid, and interfacial configurations derived from density functional theory (DFT) calculations. Benchmarking against experiment and DFT data demonstrated significant improvements over the widely used classical Embedded Atom Method (EAM) potential, particularly in predicting defect e…

Hidden Bose-Einstein Singularities in Correlated Electron Systems: III. Thermodynamic Signals
Takafumi Kita
https://arxiv.org/abs/2506.19211 https://

Hidden Bose-Einstein Singularities in Correlated Electron Systems: III. Thermodynamic Signals
We study thermodynamic consequences of the hidden Bose-Einstein singularities, which have been predicted to cause a pseudogap phase, based on quantum field theory of ordered phases. Starting from the Luttinger-Ward functional for the grand thermodynamic potential, we derive expressions of the Helmholtz free energy, internal energy, entropy, and heat capacity in a form suitable for numerical studies. They are applied to the weakly attractive Hubbard model in three dimensions to calculate the the…

Robustness of Floquet topological phase at room temperature: a first-principles dynamics study
Ruiyi Zhou, Yosuke Kanai
https://arxiv.org/abs/2506.12005 ht…

Robustness of Floquet topological phase at room temperature: a first-principles dynamics study
Nonadiabatic Thouless pumping of electrons is studied within the framework of topological Floquet engineering, particularly focused on how atomic lattice dynamics affect the emergent Floquet topological phase in trans-polyacetylene under the driving electric field. As similarly done in the earlier work [Zhou and Kanai, J. Phys. Chem. Lett., 12, 4496 (2021)], the real-time time-dependent density functional theory and Ehrenfest dynamics simulations were used to investigate the extent to which the…

First principles study of [111]-oriented epitaxially strained Rare-Earth Nickelate NdNiO$_3$
Alexander Lione, Jorge \'I\~niguez-Gonz\'alez, Nicholas C. Bristowe
https://arxiv.org/abs/2507.20819

First principles study of [111]-oriented epitaxially strained Rare-Earth Nickelate NdNiO$_3$
Density functional theory is used to investigate the effect of biaxial strain on the structural, electronic and magnetic properties of [111]-oriented NdNiO$_3$, as a representative of the rare-earth perovskites that undergo metal-to-insulator transitions. We find that this constraint on the system induces unique structural phase transitions not previously observed under the well-studied bulk or [001]-oriented strained systems. We also report unique electronic behaviour, including amplification …

Strongly correlated altermagnet CaCrO$_3$
Zhenfeng Ouyang, Peng-Jie Guo, Rong-Qiang He, Zhong-Yi Lu
https://arxiv.org/abs/2507.14081 https://

Strongly correlated altermagnet CaCrO$_3$
Altermagnetism, a newly discovered magnetic phase, has spurred growing research activity. Studies from a perspective of dynamical electronic correlation still remain scarce. Employing density functional theory plus dynamical mean-field theory (DFT+DMFT) that incorporates dynamical electronic correlation, we demonstrate that CaCrO$_3$ is a strongly correlated altermagnet. Our DFT+DMFT calculations successfully reproduce the correlated metallic behavior of CaCrO$_3$ and quantitatively capture the…

The 6H-Perovskite Dimer Lattice with Antiferromagnetic Interactions: Ba$_3$ARu$_2$O$_9$
Daniel M. Pajerowski, David A. Dahlbom, Daniel Phelan, Yu Li, Alexander I. Kolesnikov
https://arxiv.org/abs/2508.10676

The 6H-Perovskite Dimer Lattice with Antiferromagnetic Interactions: Ba$_3$ARu$_2$O$_9$
We investigate the magnetic behavior of the 6H-perovskite dimer lattice Ba$_3$Zn$_{1-x}$Ca$_x$Ru$_2$O$_9$ using analytical theory, density functional theory, inelastic neutron scattering, and modeling of historical magnetization and neutron-scattering data. A dimer mean-field theory built upon classical Luttinger-Tisza analysis generates a phase diagram revealing a transition from a nonmagnetic singlet to a finite-moment ground state as interdimer couplings increase. A (generalized) linear spin…