Optics
Optical Waveguide-Pair Design for CMOS-Compatible Hybrid III-V-on-Silicon Quantum Dot Lasers
Peter Raymond Smith, Konstantinos Papatryfonos and David R. Selviah
The development of compact, energy-efficient integrated
lasers operating at 1.3 um remains a critical focus in silicon photonics, essential for advancing data communications and optical interconnect technologies. This paper presents a numerical study of distributed Bragg reflector (DBR) hybrid III-V-on-silicon
lasers, analyzing design trade-offs and optimization strategies based on supermode theory. The III-V section of the design incorporates InAs/(Al)GaAs
quantum dots (QDs), which offer improved temperature insensitivity at the cost of more complex III-V/Si optical coupling, due to the high refractive index of (Al)GaAs. Consequently, many current
laser designs rely on silicon waveguides with a thickness exceeding 220 nm, which helps coupling but limits their compatibility with standard CMOS technologies. To address this challenge, we perform detailed simulations focusing on 220-nm-thick silicon waveguides. We first examine how the mode profiles jointly depend on the silicon waveguide dimensions and the geometry and composition of the III-V stack. Based on this analysis, we propose a novel epitaxial design that enables effective III-V/Si coupling, with the optical mode strongly confined within the III-V waveguide in the gain section and efficiently transferred to the silicon waveguide in the passive sections. Moreover, the final design is shown to be robust to fabrication-induced deviations from nominal parameters.
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Atomic Physics
Diffuse Laser Cooling Based on the $6\mathrm{P}_{3/2}$ Excited State of Rubidium Atoms via 420 nm Blue Light
Jia Zhang, Xun Gao Zheng Xiao, Xiaolei Guan Ruihang Chen et al. (+2 more)
To date, the
laser cooling of rubidium atoms has inevitably relied on 780 nm cooling light corresponding to the first excited state $5\mathrm{P}_{3/2}$. Surprisingly, we demonstrate
laser cooling directly utilizing 420 nm blue light for active optical clock, which corresponds to the high excited state $6\mathrm{P}_{3/2}$ of Rb atom. Experimentally, we successfully apply the 420 nm diffuse
laser cooling technique to prepare a cold $^{87}\mathrm{Rb}$ atomic cloud with a length of up to one meter, and measure the cold-atom absorption spectroscopy. The cold atom number is approximately $4.4\times10^{7}$. We systematically compare the cooling effects of 420 nm and 780 nm diffuse
laser cooling, and verify the feasibility of blue light cooling using high excited state. This work directly employs blue light to cool and manipulate ground-state Rb atoms to the 6P excited state, providing a new and efficient approach for the cold-atom active optical clock. It is also expected to open up research directions and application prospects in frontier fields such as Rydberg atoms, ultracold
quantum gases Bose-Einstein condensation,
quantum information, and so on.
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All authors Jia Zhang, Xun Gao Zheng Xiao, Xiaolei Guan Ruihang Chen, Mengyuan Han Tiantian Shi, Jingbiao Chen
Instrumentation and Detectors
Multiplexed SiPM Readout of Plastic Scintillating Fiber Detector for Muon Tomography
Chenghan Lv, Kun Hu, Huiling Li et al. (+5 more)
Muon tomography is a non-destructive imaging technique that uses
cosmic-ray
muons to probe dense materials. Bar scintillator and scintillating fiber detectors equipped with one-dimensional SiPM arrays offer compact, high-resolution solutions, but large-area implementations require effective reduction of readout channels while preserving detector performance. To address this challenge, we present a novel multiplexing scheme based on a diode-based symmetric charge division
circuit combined with a position-encoding
algorithm, enabling up to $N_{\textrm{SiPM}}^{\textrm{max}}=C^{2}_{N_{\textrm{ele}}}$ SiPM channels to be read out using only ${N_{\textrm{ele}}}$ electronic channels.
Circuit simulations confirm the feasibility of the multiplexing design and guide the choice of appropriate diodes to preserve SiPM signal integrity. The approach was validated using a SciFi detector module comprising 21 SiPM channels multiplexed into 7 electronic channels. Electronic tests show that this multiplexing
circuit exhibits low crosstalk between electronic channels, and preserves linearity over a dynamic range from $\sim$10 to 122 photoelectrons.
Cosmic-ray measurements further show that the multiplexed SciFi detector achieves a detection efficiency above 95% and a spatial resolution of about 0.65~mm, with only minor degradation compared to the direct (per SiPM channel) readout. These results verify that the proposed method provides a scalable and cost-effective readout solution for large-area
muon tomography systems and is applicable to other scintillator-based detectors employing similar one-dimensional SiPM array readout.
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All authors Chenghan Lv, Kun Hu, Huiling Li, Hui Liang, Cong Liu, Hongbo Wang, Zibing Wu, Weiwei Xu
Biological Physics · Cross-listed from cond-mat.soft
Neural optimization of the most probable paths of 3D active Brownian particles
Bin Zheng, Zhongqiang Xiong, Changhao Li et al. (+7 more)
We develop a variational neural-network framework to determine the most probable path (MPP) of a 3D active Brownian particle (ABP) by directly minimizing the Onsager-Machlup integral (OMI). To obtain the OMI, we use the Onsager-Machlup variational principle for active systems and construct the Rayleighian of the ABP by including its active power. This approach reveals
geometric transitions of the MPP from in-plane I- and U-shaped paths to 3D helical paths as the final time and net displacement are varied. We also demonstrate that the initial and final boundary conditions have a significant impact on the MPPs. Our results show that neural optimization combined with the Onsager-Machlup variational principle provides an efficient and versatile framework for exploring optimal transition pathways in active and nonequilibrium systems.
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All authors Bin Zheng, Zhongqiang Xiong, Changhao Li, Zhanglin Hou, Ziluo Zhang, Xinpeng Xu, Li-Shing Lin, Kenta Ishimoto, Kento Yasuda, Shigeyuki Komura
Optics
Nanoelectromechanical spectral control of silicon bowtie nanocavities for quantum light sources
Sergei Lepeshov, Daniel Alec Farbowitz, Thor August Schimmell Weis et al. (+4 more)
We present the design, fabrication, and characterization of tunable waveguide-coupled silicon bowtie cavities with strong spatial electromagnetic field confinement. We use nanoelectromechanical in-plane actuation for the tuning, as this combines cryocompatibility with an ultralow power consumption. Our device leverages a mode volume below 0.2 cubic wavelengths in the material to reach theoretical Purcell factors above 6,500 and waveguide-coupling efficiency above 30% across the full experimentally measured spectral-tuning range of 11 nm. Notably, the Purcell factor in our cavity depends only weakly on the applied voltage. Our spectral measurements demonstrate reversible tuning of bowtie cavities, and we directly show the in-plane actuation using in-situ characterization in a scanning electron microscope. Our results constitute the first demonstration of a low-loss dielectric tunable bowtie nanocavity with strong light confinement. This solves a key issue for experiments on strong light-matter interactions for cavity
quantum electrodynamics and scalable photonic
quantum technologies.
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All authors Sergei Lepeshov, Daniel Alec Farbowitz, Thor August Schimmell Weis, Bingrui Lu, Babak Vosoughi Lahijani, Mikkel Heuck, Søren Stobbe
Atmospheric and Oceanic Physics · Cross-listed from astro-ph.EP
Coupled atmospHere Interior modeL Intercomparison (CHILI) Protocol Version 1.0: A CUISINES Intercomparison Project of Magma Ocean Models
Tim Lichtenberg, Laura Schaefer, Joshua Krissansen-Totton et al. (+23 more)
Spectroscopic characterization of rocky
exoplanets with the James Webb Space
Telescope has brought the origin and
evolution of their atmospheres into the focus of
exoplanet science. Time-evolved models of the feedback between interior and atmosphere are critical to predict and interpret these observations and link them to the
Solar System terrestrial
planets. However, models differ in methodologies and input data, which can lead to significant differences in interpretation. In this paper, we present the experimental protocol of the Coupled atmospHere Interior modeL Intercomparison (CHILI) project. CHILI is an (exo-)
planet model intercomparison project within the Climates Using Interactive Suites of Intercomparisons Nested for
Exoplanet Studies (CUISINES) framework, which aims to support a diverse set of multi-model intercomparison projects in the
exoplanet community. The present protocol includes the initial set of participating magma ocean models, divided into evolutionary and static models, and two types of test categories, one focused on
Solar System
planets (Earth & Venus) and the other on
exoplanets orbiting low-mass M-
dwarfs. Both test categories aim to quantify the
evolution of key markers of the links between planetary atmospheres and interiors over geological timescales. The proposed tests would allow us to quantify and compare the differences between coupled atmosphere-interior models used by the
exoplanet and planetary science communities. Results from the proposed tests will be published in dedicated follow-up papers. To encourage the community to join this comparison effort and as an example, we present initial test results for the early Earth and TRAPPIST-1 b, conducted with models differing in the treatment of energy transport in the planetary interior and atmosphere, surface boundary layer, geochemistry, and the in- and outgassing of volatile compounds.
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All authors Tim Lichtenberg, Laura Schaefer, Joshua Krissansen-Totton, Yamila Miguel, Denis E. Sergeev, Philipp Baumeister, Jessica Cmiel, Leoni J. Janssen, T. Giang Nguyen, Yoshinori Miyazaki, Harrison Nicholls, Alexandra Papesh, Hugo Pelissard, Bo Peng, Junellie Perez, Emma Postolec, Mariana Sastre, Arnaud Salvador, Hanno Spreeuw, Andrea Zorzi, Thomas J. Fauchez, Keiko Hamano, Jérémy Leconte, Maxime Maurice, Lena Noack, Laurent Soucasse
Optics
CoSP: Reconfigurable Multi-State Metamaterial Inverse Design via Contrastive Pretrained Large Language Model
Shujie Yang, Xuzhe Zhao, Yuqi Zhang et al. (+2 more)
Metamaterials, known for their ability to manipulate light at subwavelength scales, face significant design challenges due to their complex and sophisticated structures. Consequently, deep learning has emerged as a powerful tool to streamline their design process. Reconfigurable multi-state metamaterials (RMMs) with adjustable parameters can switch their optical characteristics between different states upon external stimulation, leading to numerous applications. However, existing deep learning-based inverse design methods fall short in considering reconfigurability with multi-state switching. To address this challenge, we propose CoSP, an intelligent inverse design method based on contrastive pretrained large
language model (LLM). By performing contrastive pretraining on multi-state spectrum, a well-trained spectrum encoder capable of understanding the spectrum is obtained, and it subsequently interacts with a pretrained LLM. This approach allows the model to preserve its linguistic capabilities while also comprehending Maxwell's Equations, enabling it to describe material structures with target optical properties in natural
language. Our experiments demonstrate that CoSP can design corresponding thin-film metamaterial structures for arbitrary multi-state, multi-band optical responses, showing great potentials in the intelligent design of RMMs for versatile applications.
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All authors Shujie Yang, Xuzhe Zhao, Yuqi Zhang, Yansong Tang, Kaichen Dong
Accelerator Physics
Characteristics of electromagnetic radiation and the interference protection on a small-sized direct-acting electron accelerator with a plasma opening switch
D.V. Vinnikov, O.M. Ozerov, V.V. Katrechko et al. (+7 more)
An experimental study of the parameters of electromagnetic and X-ray radiation was carried out on a small-sized direct-acting electron accelerator with inductive storage and a
plasma opening switch. Frequency spectra have been determined, and the diagnostics of the power of the microwave component of the spectrum has been tested. An analytical comparison of radiation signals and power signals has been carried out. A method for determining the directivity pattern using a broadband power sensor has been proposed. An anechoic chamber and a reflective screen were used to suppress interference.
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All authors D.V. Vinnikov, O.M. Ozerov, V.V. Katrechko, V.I. Tkachov, S.V. Marchenko, V.V. Ehorenkov, S.A. Petrenko, B.O. Brovkin, O.V. Manuilenko, I.N. Onishchenko
Optics
End-to-end deep learning for superoscillatory subtraction imaging
Zhongwei Jin, Keyi Chen, Qiuyu Ren et al. (+7 more)
Breaking the diffraction limit in optical imaging is crucial for resolving subwavelength details in a wide range of applications, where superoscillatory imaging and subtraction imaging are two common strategies for surpassing conventional resolution limits. We propose an end-to-end deep learning framework that integrates superoscillatory focusing and subtraction imaging into a single jointly-optimized vectorial Debye integral neural network pipeline, eliminating the traditional two-step acquisition and manual weighting process. With this end-to-end neural network, we further improve the focusing capability of the system to the sub-100-nm regime, enabling deep-subwavelength imaging resolution.
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All authors Zhongwei Jin, Keyi Chen, Qiuyu Ren, Zhigang Dai, Ruoping Yao, Zhi Hong, Bin Fang, Fangzhou Shu, Shengtao Mei, Yiping Lu
Chemical Physics
Structure and Spectroscopy of Criegee Intermediates in Gas- and Aqueous Environments
Cangtao Yin, Meenu Upadhyay and Markus Meuwly
The dynamics and spectroscopy of the small (H$_2$COO) and large (CH$_3$CHOO) Criegee intermediates (CIs) in the gas phase, inside/on water droplets, on amorphous solid water (ASW) and in bulk water are investigated using validated energy functions. For both species, facile
diffusion between surface and inside positions for water droplets are found whereas on amorphous solid water at low temperatures (50 K) no surface
diffusion is observed on the multiple-nanosecond time scale. This is at variance with other species, such as CO or NO on ASW. The infrared spectroscopy of both CIs in contact with an aqueous environment leads to shifts of the spectral features on the order of a few to a few tens of cm$^{-1}$, depending on the vibrational mode considered. This is consistent with Stark-induced spectral shifts for small molecules in
protein environments. However, the spectroscopy of both CIs in contact with water droplets does not depend on the positioning relative to the droplet (inside vs. surface).
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Optics
Understanding and improving axial detection in optical tweezers based on the interference of forward- and backward- scattered light
Isaac Pérez Castillo, Simon Leturcq, Sylvain Domitin et al. (+3 more)
Fast and accurate 3D position detection in optical tweezers (OT) is essential for quantitatively monitoring subtle variations in the mechanical properties of microscopic systems ranging from biomolecules to
cells and colloids. Because standard OT configurations do not provide direct access to the axial position, axial detection typically relies on temporal fluctuations in forward-scattered optical power to infer the position of the particle. This approach generally assumes a linear-response regime in which the signal arises from the interference between the forward scattered and the nonscattered optical fields; however, under certain conditions, the backward-scattered contribution becomes non-negligible, leading to deviations from the linear response. Here, we present a simple yet comprehensive model for axial detection in standard OT while explicitly accounting for the backward-scattered field. Together with experimental validation, this framework neatly explains the standing-wave response observed when the backward-scattered field interferes with the nonscattered and the forward-scattered components, enabling accurate estimation of trap stiffness and particle
diffusion under more general conditions. This work deepens our understanding of the phenomenology observed in real optical-tweezers measurements and extends their capabilities to conditions where standard approaches fail.
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All authors Isaac Pérez Castillo, Simon Leturcq, Sylvain Domitin, Ashley L. Nord, Francesco Pedaci, Alejandro V. Arzola
Atomic Physics
Optimization of experimental parameters for laser-slowing and magneto-optical trapping of MgF molecules
Dongkyu Lim and Eunmi Chae
Diatomic molecules are promising systems for
quantum science applications due to their complex energy structures and strong dipole-dipole interactions. Achieving ultracold temperatures is essential for these applications, but the complexity of molecular energy levels requires precise optimization of experimental parameters for
laser slowing and magneto-optical trapping (MOT). Here, we simulate and optimize the complete process of slowing and trapping MgF molecules, from a buffer-gas beam source to MOT capture, using
Bayesian optimization. By combining
laser slowing and MOT simulations, we identify parameters that maximize the capture velocity and the ratio of trapped molecules. Our results demonstrate a maximum MOT capture velocity of 82.5 m/s, and 28.6% of the molecules that reach the MOT region are trapped under optimal conditions. These findings provide insights into experimental setups for MgF and similar molecules, offering a framework for advancing molecular
laser cooling and
quantum experiments.
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Optics
Single-mode magnon-polariton lasing and amplification controlled by dissipative coupling
Zi-Qi Wang, Zi-Yuan Wang, Yi-Pu Wang et al. (+1 more)
We demonstrate single-mode lasing of
magnon polaritons in a cavity magnonic system enabled by dissipative coupling between two passive modes, microwave cavity mode and
magnon mode in a ferrimagnetic
spin ensemble. The cavity mode is partially compensated through a feedback
circuit, which reduces its linewidth but retains its dissipative nature. By tuning the compensation strength and dissipative coupling strength, we reach a system cooperativity of unity, marking the lasing threshold and the formation of a zero-linewidth polariton mode. This mode also corresponds to a perfect Friedrich-Wintgen bound state in the continuum. Further increase of the cooperativity drives the system into the strong dissipative coupling regime, where
magnon polariton amplification arises between two real frequency scattering poles. These results reveal that dissipative coupling cooperativity carries a clear physical meaning and serves as a key parameter for controlling phase transitions. Dissipative coupling offers an alternative paradigm for tailoring light matter interactions, paving the way for advances in both information processing and
quantum technologies.
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All authors Zi-Qi Wang, Zi-Yuan Wang, Yi-Pu Wang, J. Q. You
Applied Physics
Moire-driven skyrmion family
Kuan He, Meng-Han Li, Shi-Da Fan et al. (+7 more)
Skyrmion family members, such as skyrmions, bimerons, and skyrmioniums, have been recently observed in
quantum, solid-state, water, and
magnetic systems. However, it remains challenging and crucial to identify a single platform for observing their coexistence and
evolution. Here, we describe a
bilayer twisted moire elastic system as a controllable platform for the generation of skyrmion family members with distinct topological charges across different wave systems. Our experimental results further reveal that the twist angle induces a synergistic
evolution between
lattice symmetry and topological characteristics, enabling the mutual transformation and stable coexistence of different skyrmion family members within a single system. More importantly, we demonstrate that such a platform supports the discontinuous transport of Lamb-wave-induced topological textures, revealing phason-like dynamics within the quasiperiodic structure. This work opens a new avenue for designing all-in-one topological wave devices.
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All authors Kuan He, Meng-Han Li, Shi-Da Fan, Zi-Bin Lin, Xiao-Ying Zhuang, Cheng-Lin Han, Li-Qun Chen, Zhao-Dong Xu, Xue-Feng Zhu, Tian-Zhi Yang
Optics
Design of Rectangular Waveguide-fed Metasurfaces for Near-Field Shaping using a Coupled Dipole Model
Insang Yoo, Dong Hwan Min, Thomas Fromenteze et al. (+1 more)
We present the design of rectangular waveguide-excited metasurfaces for near-field shaping using a coupled dipole framework. Waveguide-fed metasurfaces are array-like radiating systems typically constructed from one or more waveguides loaded with a series of subwavelength metamaterial apertures that function as radiators. The use of subwavelength radiating elements distributed across the aperture enables electromagnetic field control with subwavelength precision, offering significant potential for near-field shaping. Leveraging these capabilities, we demonstrate that the near-field patterns of rectangular waveguide-fed metasurfaces can be tailored using the coupled dipole model, which accounts for mutual interactions between metamaterial radiating elements. The validity and effectiveness of the proposed approach are verified through full-wave simulations and experiments in the X-band.
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All authors Insang Yoo, Dong Hwan Min, Thomas Fromenteze, Okan Yurduseven
Data Analysis and Statistics
Identifying statistical indicators of temporal asymmetry using a data-driven approach
Teresa Dalle Nogare and Ben D. Fulcher
The dynamics of time-reversible systems are statistically indistinguishable when observed forward or backward in time. A rich literature of statistical methods to distinguish irreversible dynamics from the reversible dynamics of linear, Gaussian systems can provide insights into underlying mechanisms and aid modeling and statistical quantification of time-series data. But these existing time-reversibility metrics have been developed individually, forming a fragmented body of research that makes it challenging to identify the most effective approaches developed to date, and the most promising new directions for development. Here we address these issues by systematically evaluating over 6000 time-series summary statistics, derived from across the time-series analysis literature, on their ability to distinguish the time-irreversibility of data simulated from a diverse range of 35 systems. Our large-scale data-driven comparison highlights the effectiveness of several key families of statistics, including time-asymmetric forms of generalized autocorrelation functions, time-series symbolic sequences, and
forecasting-related methods. All irreversible systems studied here could be accurately distinguished by a well-chosen time-series statistic, but no single statistic could accurately index the statistical form of irreversibility for all irreversible systems. This challenges the assumption that a given time-reversibility statistic will accurately capture time reversibility in general, and underscores the importance of tailoring statistical approaches to the time-reversal characteristics of a given system. Our results provide a unified understanding of the key algorithmic structures through which irreversibility can be effectively quantified from data, providing a foundation for connecting patterns in time series to the underlying mechanisms of the systems that generate them.
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Plasma Physics
Effects of Multi-scale Coupling on Particle Acceleration and Energy Partition in Magnetic Reconnection
Alexander Velberg, Adam Stanier, Xiaocan Li et al. (+3 more)
The interplay between kinetic and macroscopic scales during
magnetic reconnection is investigated using particle-in-
cell simulations of
magnetic island coalescence in the strongly-magnetized, relativistic pair
plasma regime. For large system sizes, secondary current sheet formation and downstream
turbulence driven by the reconnection
outflows dominate the global energy dissipation so that it is causally connected, but spatially and temporally de-coupled from the primary reconnecting current sheet. When compared to simulations of an isolated, force-free current sheet, these dynamics activate additional particle acceleration channels which are responsible for a significant population of the non-thermal particles, modifying the particle energy spectra.
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All authors Alexander Velberg, Adam Stanier, Xiaocan Li, Fan Guo, William Daughton, Nuno F. Loureiro
Fluid Dynamics
Local and global bifurcations to large-scale oblique patterns in inclined layer convection
Zheng Zheng, Sajjad Azimi, Florian Reetz et al. (+1 more)
In the inclined layer convection system, thermal convection in a Rayleigh–Bénard
cell tilted against
gravity, the flow is subject to competing buoyancy and shear forces. For varying inclination angle ($\gamma$) and Rayleigh number ($Ra$), a variety of spatio-temporal patterns is observed. We investigate the switching diamond panes (SDP) pattern, observed at $(\gamma, Ra)\simeq(100\degree,10000)$, which exhibits large-scale oblique features and is one of the five complex tertiary patterns at Prandtl number $Pr=1.07$. First, we study the linear instability of the secondary-state transverse convection rolls and the five branches including two travelling waves and three periodic orbits, bifurcating simultaneously from it. These non-generic bifurcations arise from the breaking of the spatial $D_4$ and $O(2)$
symmetries of transverse rolls, and the resulting bifurcated solutions show large-scale diamond-shaped amplitude modulations. Second, we explore a periodic orbit that captures both the large-scale structure and small-scale defects of modulated rolls. Parametric continuation in $Ra$ reveals the global homoclinic bifurcation via which this periodic orbit emerges. Third, the boundary of the basins of attraction of two dynamically relevant periodic orbits has been characterised. Specifically, additional steady and time-periodic solutions are identified on the basin boundary and their bifurcation structures are analysed. Together, using non-linear invariant solutions and their bifurcations, we take a further step toward understanding the emergence and dynamics of SDP far from the onset of convection, where linear methods have not been applied successfully.
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All authors Zheng Zheng, Sajjad Azimi, Florian Reetz, Tobias M. Schneider
Optics
Near-Field Topology-Optimized Superchiral Metasurfaces for Enhanced Chiral Sensing
Zhongjun Jiang, Soyaib Sohag and You Zhou
The detection and discrimination of molecular chirality are essential for advancing pharmaceutical and biological applications. While nanophotonic platforms offer a route to enhance
chiral light-matter interactions, existing device concepts for
chiral sensing remain heuristic, resulting in limited
chiral enhancement and control over
chiral hotspot placement within nanostructures. Here, we introduce an inverse-design framework that directly optimizes superchiral near fields in photonic nanostructures and demonstrate its powerful opportunities for enantioselective analysis. We first show that freeform achiral metasurfaces can be optimized to achieve an 800-fold
chiral density enhancement, with fully customizable
chiral hotspot placement for direct molecular interaction. We further demonstrate ultrasensitive detection of
chiral analytes and achieve a 116-fold increase in detection sensitivity over the native enantiomeric response. Lastly, we extend our platform to determine
chiral-molecule concentration and resolve enantiomeric excess in
chiral mixtures. Our framework offers a generic route to enabling nanophotonic platforms for detecting
chiral compounds and can be integrated with a broad range of
spin-based photonic materials for applications in valleytronics,
chiral emission control, and topological photonics.
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Medical Physics
PySERA: Open-Source Standardized Python Library for Automated, Scalable, and Reproducible Handcrafted and Deep Radiomics
Mohammad R. Salmanpour, Amir Hossein Pouria, Sirwan Barichin et al. (+5 more)
Radiomics enables the extraction of quantitative biomarkers from medical images for precision modeling, but reproducibility and scalability remain limited due to heterogeneous software implementations and incomplete adherence to standards. Existing tools also lack unified support for deep learning based radiomics. To address these limitations, we introduce PySERA, an open source, Python native, standardized radiomics framework designed for automation, reproducibility, and seamless AI integration. PySERA reimplements the MATLAB based SERA platform within a modular, object oriented architecture and computes 557 features, including 487 Image Biomarker Standardization Initiative (IBSI) compliant features, 10 moment invariant descriptors, and 60 diagnostic features, together with deep learning radiomics
embeddings from pretrained networks such as ResNet50, DenseNet121, and VGG16. The framework provides standardized preprocessing, including resampling, discretization, and normalization, multi format image input and output, adaptive
memory management, and a parallel multicores extraction engine. PySERA integrates natively with major machine learning ecosystems including scikit learn, PyTorch, TensorFlow, MONAI and others. In IBSI
benchmarks, PySERA achieved more than 94 percent reproducibility and outperformed PyRadiomics while closely matching MITK. Across eight public
datasets, it achieved predictive accuracies ranging from 0.54 to 0.87, consistently exceeding PyRadiomics. PySERA unifies handcrafted and deep learning radiomics in a transparent, scalable, and extensible Python framework, establishing a robust foundation for reproducible, AI ready imaging research.
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All authors Mohammad R. Salmanpour, Amir Hossein Pouria, Sirwan Barichin, Yasaman Salehi, Sonya Falahati, Isaac Shiri, Mehrdad Oveisi, Arman Rahmim
Atomic Physics · Cross-listed from quant-ph
High-Fidelity Raman Spin-Dependent Kicks in the Presence of Micromotion
Haonan Liu, Varun D. Vaidya, Monica Gutierrez Galan et al. (+3 more)
We propose high-fidelity single-
qubit spin-dependent kicks (SDKs) for trapped ions using nanosecond Raman pulses via amplitude modulation of a continuous-wave
laser with a tunable beat frequency. We develop a general method for maintaining SDK performance in the presence of micromotion by identifying optimal choices of the RF phase and frequency that suppress unwanted backward kicks. The proposed scheme enables SDK infidelities as low as $10^{-9}$ in the absence of micromotion, and below $10^{-5}$ with micromotion. This study lays the foundation for the realization of sub-trap-period and high-fidelity two-
qubit gates based on SDKs.
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All authors Haonan Liu, Varun D. Vaidya, Monica Gutierrez Galan, Alexander K. Ratcliffe, Amrit Poudel, C. Ricardo Viteri
Atomic Physics · Cross-listed from cond-mat.quant-gas
A low-energy effective Hamiltonian for Landau quasiparticles: I. A unified theory of transport and superfluidity in Fermi liquids
Pierre-Louis Taillat and Hadrien Kurkjian
We introduce a new renormalisation scheme to construct the Landau quasiparticles of
Fermi fluids. The scheme introduces an energy cutoff $\Lambda$ to remove the resonant couplings, enabling the dressing of the particles into quasiparticles via a
unitary transformation. The dynamics of the quasiparticles is then restricted to low-energy transitions and is fully determined by an effective
Hamiltonian which unifies the Landau function $f$, the pair interaction $g$ responsible for superfluidity, and the collision amplitude $\mathcal{A}$ responsible for transport and equilibration. Studying the flow equation that results from infinitesimal variations of the cutoff, we recover the Bethe-Salpeter relation between $f$ and the forward limit of $\mathcal{A}$, and we demonstrate an analogue relation between $g$ and the frontal limit of $\mathcal{A}$. We show that our effective theory captures all the low-energy phenomena of
Fermi liquids, from the equation of state to the transport properties, both in the normal and in the superfluid phase. We apply it to the calculation of non-
Fermi liquid corrections to the quasiparticle lifetime. This publication is continued by arXiv:2607.07041 where we apply the effective theory to a
Fermi fluid of ultracold atoms.
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Plasma Physics
Asymptotic-preserving semi-implicit finite volume scheme for Extended Magnetohydrodynamics
Yi Han Toh, Joshua Dolence and Karthik Duraisamy
A Finite Volume (FV) scheme is developed for solving the extended magnetohydrodynamic (XMHD) equations, yielding accurate results in the ideal, resistive, and
Hall MHD limits. This is accomplished by first re-writing the XMHD equations such that it allows the
algorithm to retain the use of ideal MHD Riemann solvers and the constrained transport method to preserve divergence-free
magnetic fields. Incorporation of electron inertia and displacement current introduces additional numerical stiffness which motivates a semi-implicit FV scheme that re-formulates the XMHD model as a relaxation system. The equations are then advanced in time using an explicit 2nd-order Runge-Kutta scheme with operator splitting applied to the implicit source term updates at each sub-stage. For additional numerical stability, a density-dependent slope limiter is implemented to increase flux diffusivity at low density regions where non-ideal effects become significant. The
algorithm is subsequently implemented in a scalable adaptive mesh refinement (AMR) framework. As the new
algorithm retains many aspects of the ideal MHD formulations, it asymptotes naturally to the ideal MHD limit. Moreover, it shows promising results at the resistive and
Hall MHD limits. This is verified against reference test problems for ideal, resistive and
Hall MHD.
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