arXivDaily arXiv每日学术速递 周一至周五更新
重置
全部学科分类 1401
热门方向导航
2606.19238 2026-06-18 physics.med-ph 新提交

Introduction to Quantum Ophthalmology

量子眼科学导论

Mukhit Kulmaganbetov, Dmitry Pushin, Taranjit Singh, Pinki Chahal, David Cory, Iman Salehi, Andrew Silva, Ben Thompson, Dusan Sarenac

AI总结 本文探讨量子技术在眼科学中的四种应用方向:光子受限视网膜成像、关联成像、纳米光学探针和量子极限视觉感知,展示了量子方法在提升成像质量和研究视觉功能方面的潜力。

详情
AI中文摘要

量子技术正在多个研究领域迅速发展,对生物医学成像和传感的影响日益增大。我们通过四个互补方向考察其在眼科学中的新兴作用:光子受限视网膜成像、基于关联的成像、纳米光学探针和量子极限视觉感知。光学相干断层扫描和单光子探测的进步使得在严格光子预算限制下成像成为可能,在保持图像质量的同时减少光毒性。基于关联的方法(包括鬼成像)为低光和散射环境下的图像形成提供了替代策略,尽管实际实施仍受限于检测效率和采集时间。同时,纳米级光学平台(如量子点)提供了可调谐且光稳定的探针,用于增强对比度和靶向递送,但生物相容性和临床转化仍面临挑战。最后,单光子水平和结构光场实验表明,视觉系统本身在接近物理检测极限下运行,并可通过受控光学状态进行探测。尽管这些方法大多仍处于早期阶段,但它们共同展示了量子及量子启发方法如何增强当前的眼科成像和诊断技术,同时为在明确物理约束下研究视觉功能提供新工具。

英文摘要

Quantum technologies are rapidly advancing across multiple research domains, with a growing impact on biomedical imaging and sensing. We examine their emerging role in ophthalmology through four complementary directions: photon-limited retinal imaging, correlation based imaging, nanoscale optical probes, and quantum-limited visual perception. Advances in optical coherence tomography and single-photon detection enable imaging under strict photon budget constraints, reducing phototoxicity while preserving image quality. Correlation-based approaches, including ghost imaging, offer alternative strategies for image formation in low-light and scattering environments, although practical implementation remains limited by detection efficiency and acquisition time. In parallel, nanoscale optical platforms such as quantum dots provide tunable and photostable probes for enhanced contrast and targeted delivery, with ongoing challenges related to biocompatibility and clinical translation. Finally, experiments at the single-photon level and with structured light fields demonstrate how the visual system itself operates near physical detection limits and can be probed using controlled optical states. While many of these approaches remain at an early stage, they collectively illustrate how quantum and quantum-inspired methods may augment current ophthalmic imaging and diagnostic technologies while providing new tools for studying visual function under well-defined physical constraints.

2606.19205 2026-06-18 physics.comp-ph 新提交

Discovering a well-conditioned analytic continuation problem via dictionary learning

通过字典学习发现一个良态解析延拓问题

Thomas Chuna, Phil-Alexander Hofmann, Alexander Benedix-Robles, Tobias Dornheim

AI总结 提出正则化随机优化方法(RSOM),将解析延拓重构为字典学习问题,发现稀疏字典将病态逆问题映射为良态低维问题,在合成测试和电子气QMC数据上表现优异。

Comments 25 pages, 8 figures, 3 algorithms, to be submitted to Computer Physics Communications

详情
AI中文摘要

许多物理学领域使用量子蒙特卡洛(QMC)模拟来模拟虚时 $\tau$ 中的量子系统,并估计虚时关联函数(ITCF)。然而,从ITCF中提取动态 $\omega$ 依赖的量是一个众所周知的困难任务,称为解析延拓(AC),它相当于求解一个指数级病态的逆问题。在AC文献中,存在竞争性的随机方法和正则化方法,以及新兴的使用参数化模型(如神经网络)的工作。在这里,我们超越了这些社区之间的传统界限,引入了正则化随机优化方法(RSOM)。该方法将AC重新表述为一个字典学习问题,发现一个稀疏字典来表示解。我们的方法受到字典学习在许多科学领域产生的惊人结果的启发。值得注意的是,RSOM发现了一个稀疏字典,将病态逆问题映射到一个良态的低维问题。我们证明,该方法在常见的合成测试问题以及来自有限温度电子气的真实QMC数据上都能产生有竞争力的结果。这项工作揭示了在所有随机和正则化方法中都存在一个字典,并且字典学习为未来的AC方法提供了新的攻击角度。

英文摘要

Many fields of physics use quantum Monte Carlo (QMC) simulations to simulate quantum systems in imaginary-time $τ$ and estimate imaginary-time correlation functions (ITCF). However, extracting dynamic $ω$-dependent quantities from ITCFs is a notoriously difficult task, known as analytic continuation (AC), that amounts to solving an exponentially ill-conditioned inverse problem. Within the AC literature, there are competing stochastic and regularized approaches, as well as an emerging collection of works using parameterized models like neural networks. Here we transcend the traditional divides between the communities, introducing the regularized stochastic optimization method (RSOM). This method reformulates AC as a dictionary learning problem, discovering a sparse dictionary to represent the solution. Our approach is motivated by the astounding results dictionary learning has produced in many scientific fields. Remarkably, RSOM discovers a sparse dictionary that maps an ill-conditioned inverse problem to a low-dimensional problem that is well-conditioned. We demonstrate that the method yields competitive results for common synthetic test problems as well as for authentic QMC data from the finite temperature electron gas. This work exposes that a dictionary exists within all stochastic and regularized methods and that dictionary learning provides a new angle of attack for future AC methods.

2606.19165 2026-06-18 physics.optics 新提交

High-speed electrically driven liquid-crystal compact optical skyrmion encoder

高速电驱动液晶紧凑型光学斯格明子编码器

Yu-Ping Tang, Zhenyu Guo, Ze-Yu Wang, Le Yu, Long-Yang Wang, Nilo Mata-Cervera, Yu Wang, Ning Wang, Yijie Shen, Ling-Ling Ma, Yan-Qing Lu

AI总结 提出基于图案化液晶自旋轨道器件的高速可切换光学斯格明子发生器,通过电压调控液晶延迟实现斯格明子态与非斯格明子态的可逆切换,响应时间达毫秒级,循环速率约403 Hz,并展示了图像编码解码应用。

Comments 15 pages, 5 figures

详情
AI中文摘要

光学斯格明子具有拓扑偏振纹理,能在外部扰动下保持拓扑鲁棒性,使其成为抗干扰光学信息传输的有前景载体。然而,现有光学斯格明子生成方案大多依赖静态光学元件或固定纳米结构,难以实现拓扑态的高速动态切换。这里,我们提出一种基于图案化液晶自旋轨道器件的高速可切换光学斯格明子发生器。该器件利用液晶的面内取向来印刻固定的Pancharatnam-Berry几何相位,同时施加电压快速调节液晶延迟,实现斯格明子态与非斯格明子态的可逆切换。实验结果表明,该器件具有毫秒级电响应,双向响应时间分别为1.76 ms和0.72 ms,对应理想循环速率约403 Hz,使其成为迄今为止最快的可切换光学斯格明子发生器。此外,通过利用这种快速拓扑刷新能力,我们演示了图像编码和解码,为高速、可刷新、抗干扰的拓扑光学信息传输提供了新的液晶器件平台。

英文摘要

Optical skyrmions possess topological polarization textures that can maintain topological robustness under external perturbations, making them promising carriers for disturbance-resistant optical information transmission. However, existing optical skyrmion generation schemes mostly rely on static optical elements or fixed nanostructures, making high-speed dynamic switching of the topological state difficult. Here, we propose a high-speed switchable optical skyrmion generator based on a patterned liquid-crystal spin-orbit device. The device employs the in-plane orientation of liquid crystals to imprint a fixed Pancharatnam-Berry geometric phase, while an applied voltage rapidly tunes the liquid-crystal retardance, enabling reversible switching between skyrmion and non-skyrmion states. Experimental results show that the device exhibits millisecond electrical response, with bidirectional response times of 1.76 ms and 0.72 ms, corresponding to an ideal cycling rate of approximately 403 Hz, making it the fastest switchable optical skyrmion generator to date. Furthermore, by exploiting this rapid topological refreshing capability, we demonstrate image encoding and decoding, providing a new liquid-crystal device platform for high-speed, refreshable, and disturbance-resistant topological optical information transmission.

2606.19114 2026-06-18 physics.optics 新提交

Extreme mid-infrared field enhancement and anapoles in high-index plasmonic metamaterials

高折射率等离激元超材料中的极端中红外场增强与anapole

Zoltan Sztranyovszky, Nicolas Spiesshofer, Caleb Todd, Rakesh Arul, Yeeun Roh, Rohit Chikkaraddy, Jeremy J. Baumberg, Angela Demetriadou

AI总结 本文基于金纳米颗粒自组装超材料,实现中红外波段有效折射率超过15且间隙场增强两个数量级,并通过设计支持anapole的紧凑超材料器件进一步增强纳米间隙场,使量子发射器的受激辐射响应增强三个数量级。

详情
AI中文摘要

高折射率材料支撑着广泛的光学技术,包括通信、成像、激光器和集成光子学系统。在这里,我们展示了一种基于金纳米颗粒聚集体的自组装超材料平台,其纳米尺度间隙在中红外波段表现出超过15的极高有效折射率,同时产生至少两个数量级的间隙场增强。这种高折射率和极端场增强的结合实现了异常强的光-物质相互作用。我们通过设计一个紧凑的高折射率超材料器件来演示这一点,该器件支持anapole,进一步增强了纳米间隙场。通过将具有太赫兹跃迁的量子发射器放置在等离激元间隙内,我们展示了受激辐射响应增强了至少三个数量级,突显了在非线性光学、频率上转换和振动强耦合中的应用。

英文摘要

High-refractive-index materials underpin a wide range of optical technologies, including communications, imaging, lasers, and integrated photonic systems. Here, we demonstrate a self-assembled metamaterial platform based on gold nanoparticle aggregates with nanometer-scale gaps exhibit remarkably high effective refractive indices exceeding 15 in the mid-infrared regime, while simultaneously producing gap-field enhancements of at least two-orders of magnitude. This combination of high refractive index and extreme field enhancement enables exceptionally strong light-matter interactions. We demonstrate this by designing a compact high-index metamaterial device supporting an anapole, which further enhances the nanogap field. By placing quantum emitters with terahertz transitions inside the plasmonic gaps, we show a stimulated-emission response enhanced by at least three orders of magnitude, highlighting applications in non-linear optics, frequency up-conversion and vibrational strong coupling.

2606.19093 2026-06-18 physics.ao-ph 新提交

AIFS-DOP: End-to-End Medium-Range Weather Prediction from Observations Alone with Machine Learning

AIFS-DOP:仅基于观测的端到端中期天气预报机器学习方法

Ewan Pinnington, Peter Lean, Mihai Alexe, Eulalie Boucher, Simon Lang, Patrick Laloyaux, Gert Mertes, Tomas Kral, Patricia de Rosnay, Matthew Chantry, Anthony McNally

AI总结 提出AIFS-DOP模型,仅用40年网格化观测数据训练,无需数值预报再分析数据,在2021/2022年预报评分中与ECMWF的IFS系统竞争,首次实现纯数据驱动模型在中期预报中与IFS相当。

Comments 12 pages, 10 figures

详情
AI中文摘要

我们介绍了用于直接观测预测的人工智能预报系统(AIFS-DOP)。AIFS-DOP在40年的网格化观测协调数据集上训练,不使用数值天气预报(NWP)再分析或模型数据。所得模型在2021/2022年的一年预报周期评分中与ECMWF的综合预报系统(IFS)具有竞争力。直接观测预测的这一进展标志着首次有仅基于观测训练的数据驱动模型在中期范围内与IFS在多个关键高层和地面主要评分上具有竞争力,当根据观测数据验证时。

英文摘要

We introduce the Artificial Intelligence Forecasting System for Direct Observation Prediction (AIFS-DOP). AIFS-DOP is trained on a 40-year harmonized dataset of gridded observations, without using numerical weather prediction (NWP) reanalysis or model data. The resulting model is competitive with ECMWF's Integrated Forecasting System (IFS) when scored on a one year period of forecasts across 2021/2022. This progress on Direct Observation Prediction represents the first time that a data-driven model, trained solely on observations, is competitive with the IFS at medium ranges for several key upper-air and surface headline scores, when verified against observation data.

2606.19018 2026-06-18 physics.flu-dyn math.AP 新提交

Global branches of Stokes waves of variable period on stratified fluids

分层流体上变周期Stokes波的全局分支

Vladimir Kozlov

AI总结 研究二维通道中分层稳态水波,考虑从层流分岔的Stokes波分支,以波周期为参数,提出新密度和Bernoulli函数类,使层流产生全局分岔分支,且分岔周期可任意大。

详情
AI中文摘要

我们考虑二维通道中的分层稳态水波。研究对象是从层流分岔的Stokes波分支。假设质量通量和Bernoulli常数固定,并将波的周期视为参数,其值可沿分支变化。提出了一类新的密度和Bernoulli函数,使得层流产生全局分岔分支。层流不一定是单向的,我们证明分岔分支可以从具有任意大周期的层流分岔出来。

英文摘要

We consider stratified steady water waves in a two dimensional channel. Our subject is branches of Stokes waves, bifurcating from laminar flows. We assume that the mass flux and the Bernoulli constant are fixed and consider the period of the wave as a parameter, which can change its value along the branch. A new class of density and Bernoulli functions is presented, for which laminar flows generate global bifurcation branches. The laminar flows are not necessary unidirectional and we show that the bifurcation branch can bifurcate from the laminar flow with arbitrary large period.

2606.18995 2026-06-18 physics.flu-dyn 新提交

Intermittency in Shell Models of Turbulent Cascades: from Single-Branch to Multi-Branch

湍流级联壳模型中的间歇性:从单分支到多分支

Flavio Tuteri, Sergio Chibbaro, Alexandros Alexakis

AI总结 通过多分支壳模型研究湍流间歇性,发现分支结构增强了间歇性,并建议简化描述需保留非线性动力学和几何组织。

详情
AI中文摘要

间歇性是湍流传输的核心特征之一:多尺度能量级联由罕见且强烈的涨落介导。我们在一个多分支壳模型中研究了这一现象,该模型将准局部三对角非线性相互作用与模拟小尺度自由度增长的分支结构相结合。与标准Sabra模型的比较表明,分支增强了间歇性,这由能量通量结构函数的异常标度指数测量。我们进一步使用乘数统计和大偏差估计来表征级联的乘性本质。我们的结果表明,湍流间歇性的简化描述应同时保留非线性动力学和几何组织。讨论了对Navier-Stokes湍流的启示。

英文摘要

Intermittency is one of the central features of turbulent transfer: the multi-scale energy cascade is mediated by rare and intense fluctuations. We investigate this phenomenon in a multi-branch shell model, which combines quasi-local triadic nonlinear interactions with a branching structure that mimics the growth of degrees of freedom toward small scales. Comparison with the standard Sabra model shows that branching enhances intermittency, as measured by anomalous scaling exponents of energy-flux structure functions. We further use multiplier statistics and large deviation estimates to characterize the multiplicative nature of the cascade. Our results suggest that reduced descriptions of turbulent intermittency should retain both nonlinear dynamics and geometrical organization. Implications on Navier-Stokes turbulence are discussed.

2606.18990 2026-06-18 physics.med-ph cs.NA math.NA 新提交

Quantitative Multi-Modal Optical Coherence Photoacoustic Elastography

定量多模态光学相干光声弹性成像

Ekaterina Sherina, Lisa Krainz, Wolfgang Drexler, Otmar Scherzer

AI总结 提出结合光学相干断层扫描(OCT)和光声断层扫描(PAT)的多模态弹性成像框架,通过混合反演算法融合互补信息,在硅胶体模上实现更高信噪比和更准确的刚度估计。

Comments 16 pages, 17 figures, 3 tables

详情
AI中文摘要

我们提出了一种新颖的多模态光学相干光声弹性成像(OCPE)框架,该框架结合了两种成像模态——光学相干断层扫描(OCT)和光声断层扫描(PAT),通过准静态弹性成像实现互补的吸收-散射测量,以提取定量组织特征。为此,我们开发了一种复杂的混合反演算法,用于融合OCT和PAT弹性成像测量中包含的互补信息层,并进行系统评估以评估混合弹性成像数据对应变和刚度重建的影响。在硅弹性体体模上的研究表明,OCT-PAT联合方法优于单模态OCT弹性成像和PAT弹性成像,产生更高的应变信噪比和改进的刚度估计。这些结果确立了多模态互补成像和数据融合在散射和吸收材料中进行准确、高分辨率弹性应变和刚度映射的优势。

英文摘要

We present a novel multi-modal optical coherence photoacoustic elastography (OCPE) framework, which combines two imaging modalities, optical coherence tomography (OCT) and photoacoustic tomography (PAT), to enable complementary absorption-scattering measurements for the extraction of quantitative tissue features via quasi-static elastography. For this, we develop a sophisticated hybrid inversion algorithm for merging the complementary information layers contained in both OCT and PAT-based elastography measurements, and perform systematic evaluations to assess the impact of hybrid elastography data on strain and stiffness reconstructions. Studies on a silicone elastomer phantom demonstrate that the combined OCT-PAT approach outperforms single-modality OCT elastography and PAT elastography, yielding higher strain signal-to-noise ratio and improved stiffness estimates. These results establish the advantage of multi-modal complementary imaging and data merging for accurate, high-resolution elastographic strain and stiffness mapping in both scattering and absorbing materials.

2606.18927 2026-06-18 physics.flu-dyn 新提交

APU-Accelerated Large Eddy Simulation with the Discontinuous Galerkin Solver GALÆXI

APU加速的间断伽辽金求解器GALÆXI大涡模拟

Spencer Starr, Anna Schwarz, Justin Du Plessis, Andreas Wanninger, Johanna Hintz, Rohan Kaushik, Patrick Kopper, Andrea Beck

AI总结 针对异构GPU架构,提出架构无关的DGSEM框架GALÆXI,在AMD MI300A APU上实现强/弱扩展分析,集成壁模型大涡模拟算法,并通过跨音速压气机叶栅算例验证其捕捉激波/湍流边界层相互作用的能力。

详情
AI中文摘要

由异构GPU架构驱动的百亿亿次计算时代,要求对传统CFD求解器进行根本性重新设计,以充分利用这些异构系统。间断伽辽金谱元法(DGSEM)因其高阶精度和局部计算模板,为这一转变提供了理想基础。本文通过连接硬件优化、软件实现和物理验证,展示了架构无关的DGSEM框架GALÆXI在开发和应用方面的最新进展。分析了GALÆXI在Hunter超级计算机上的AMD MI300A加速处理单元(APU)上的性能。具体而言,评估了强扩展和弱扩展性能,以及AMD MI300A上可用的计算分区模式的影响。其次,概述了将壁模型大涡模拟所需算法集成到GPU加速框架中的策略。通过平面湍流通道算例验证了这些算法。最后,将该求解器应用于一个高要求的流动问题——跨音速压气机叶栅的壁分辨大涡模拟。研究结果展示了GALÆXI准确捕捉复杂激波/湍流边界层相互作用的能力。

英文摘要

The exascale computing era, driven by heterogeneous GPU architectures, requires a fundamental redesign of traditional CFD solvers to fully leverage those heterogeneous systems. The discontinuous Galerkin spectral element method (DGSEM) provides an ideal foundation for this transition due to its high-order accuracy and local computational stencil. This work presents recent advances in the development and application of the architecture-agnostic DGSEM framework GALÆXI by linking hardware optimization, software implementation, and physical validation. The performance of GALÆXI on the AMD MI300A Accelerated Processing Units (APUs) featured on the Hunter supercomputer is analyzed. Specifically, evaluations of the strong and weak scaling performance and the impact of the compute partitioning modes available on the AMD MI300As are performed. Second, the strategy used to integrate the algorithms necessary for wall-modeled large eddy simulations into the GPU-accelerated framework is outlined. Validation of those algorithms is presented in the form of a plane turbulent channel testcase. Finally, the solver is applied to a demanding flow problem in the form of a wall-resolved large eddy simulation of a transonic compressor cascade. The results from this investigation demonstrate the capabilities of GALÆXI to accurately capture complex shock-wave/turbulent boundary-layer interactions.

2606.18901 2026-06-18 physics.ao-ph physics.data-an 新提交

Multifractal Dynamics of Tropical Atlantic SST Indices: Nonlinear Scaling Structure and Episodic Statistical Association with ENSO Variability

热带大西洋海温指数的多重分形动力学:非线性标度结构与ENSO变率的间歇性统计关联

Sebastián Jaroszewicz, Nahuel Mendez, Maria P. Beccar-Varela, Maria Cristina Mariani

AI总结 利用MFDFA分析三个热带大西洋海温指数的多重分形特性,发现TASI具有更宽的多重分形谱且包含非线性贡献,移动窗口分析显示强厄尔尼诺事件期间多重分形宽度显著降低,滞后相关揭示与ENSO的间歇性关联。

详情
AI中文摘要

热带大西洋表现出由内部海洋-大气相互作用和远程气候强迫驱动的复杂海表温度(SST)变率。我们使用1981年至2025年的周数据,对三个海温指数——南大西洋热带(SAT)、热带南大西洋(TSA)和热带大西洋海温梯度指数(TASI)——进行了比较多重分形分析。多重分形去趋势波动分析(MFDFA)揭示了所有指数中稳健的尺度依赖行为。TASI显示出比SAT(0.27)和TSA(0.34)宽得多的多重分形谱(Δh约0.72)。替代数据测试表明,SAT和TSA中的多重分形性主要由线性自相关解释,而TASI包含与相位相关的额外非线性贡献。为了研究时间变率,我们引入了一个移动窗口MFDFA框架,跟踪多重分形宽度的演变。在1997-1998年和2015-2016年两次主要厄尔尼诺事件期间观察到显著减小,表明在极端太平洋强迫下多尺度变率受到抑制。滞后相关分析揭示了与海洋尼诺指数在15-18个月延迟下的显著负相关,与已知的大西洋-太平洋遥相关一致。然而,格兰杰因果性和传递熵检验未检测到显著的因果联系,表明这是一种间歇性而非持续性的关系。滞后多重分形互相关分析进一步揭示了尺度依赖的跨海盆耦合。这些结果表明,时间依赖的多重分形测度为表征非线性大西洋变率提供了一个有用的框架,并将TASI识别为一个动态独特的指数,其标度性质包含区域海温指数单独无法捕捉的信息。

英文摘要

The Tropical Atlantic exhibits complex sea surface temperature (SST) variability driven by internal ocean-atmosphere interactions and remote climate forcing. We perform a comparative multifractal analysis of three SST indices, South Atlantic Tropical (SAT), Tropical Southern Atlantic (TSA), and the Tropical Atlantic SST Gradient Index (TASI), using weekly data from 1981 to 2025. Multifractal Detrended Fluctuation Analysis (MFDFA) reveals robust scale-dependent behavior in all indices. TASI displays a substantially broader multifractal spectrum (Delta h about 0.72) than SAT (0.27) and TSA (0.34). Surrogate-data tests show that multifractality in SAT and TSA is mainly explained by linear autocorrelations, whereas TASI contains an additional nonlinear contribution associated with phase correlations. To investigate temporal variability, we introduce a moving-window MFDFA framework that tracks the evolution of multifractal width. Significant reductions are observed during the major 1997-1998 and 2015-2016 El Nino events, indicating a suppression of multiscale variability under extreme Pacific forcing. Lagged correlation analysis reveals a significant negative association with the Oceanic Nino Index at delays of 15-18 months, consistent with known Atlantic-Pacific teleconnections. However, Granger causality and Transfer Entropy tests do not detect significant causal links, suggesting an episodic rather than persistent relationship. Lagged multifractal cross-correlation analysis further reveals scale-dependent inter-basin coupling. These results demonstrate that time-dependent multifractal measures provide a useful framework for characterizing nonlinear Atlantic variability and identify TASI as a dynamically distinct index whose scaling properties contain information not captured by regional SST indices alone.

2606.18845 2026-06-18 physics.plasm-ph physics.acc-ph 新提交

Wake Perturbations in Laser- and Beam-Driven Plasma Wakefield Accelerators: A Symmetry-Based Multipole Classification

激光驱动和束驱动等离子体尾波加速器中的尾波扰动:基于对称性的多极分类

Andrei C. Berceanu, Alessio Del Dotto

AI总结 通过理想化尾波吹泡的对称性群,将尾波横向扰动按方位角多极阶数m分类,统一解释了激光和束驱动尾波加速器中的束流品质退化现象,并提出了m=3响应通道的可能性。

Comments 14 pages, 4 figures, 1 appendix

详情
AI中文摘要

我们通过理想化尾波吹泡的对称性群——轴对称性 $\mathrm{SO}(2)_\phi$、绝热纵向平移和传播方向宇称——回顾了激光驱动(LWFA)和束驱动(PWFA)等离子体尾波加速器中的束流品质物理。尾波的横向扰动由整数方位角多极阶数 $m$ 分类,该阶数标记了 $\mathrm{SO}(2)_\phi$ 的不可约表示,最低的束流品质可观测量在特定多极处耦合:束团质心在 $m=1$,交叉平面发射度耦合在 $m=2$。一个辛类比将横向匹配与纵向束加载联系起来。LWFA 和 PWFA 共有的几种现象——软管不稳定性、脉冲前沿倾斜抖动、斑点不对称发射度增长、偏振依赖的质心运动、共振交叉平面混合——占据了两个最低的非平凡 $m$ 通道,并允许统一的讨论。正电子见证问题以相同的语言重新组织:每种已知的缓解方法都放弃了均匀密度吹泡的一个特定特征,这些特征来自一个有限集合。该分类还提出了一个 $m=3$ 响应通道的可能性,其幅度尚待确定。我们注意到与等离子体加速器的对称性等变贝叶斯优化的联系。

英文摘要

We review beam-quality physics in laser-driven (LWFA) and beam-driven (PWFA) plasma wakefield accelerators through the symmetry group of the idealised blowout wake -- axisymmetry $\mathrm{SO}(2)_ϕ$, adiabatic longitudinal translation, and propagation-direction parity. Transverse perturbations of the wake are classified by an integer azimuthal multipole order $m$ labelling the irreducible representations of $\mathrm{SO}(2)_ϕ$, with the lowest beam-quality observables coupling at a specific multipole: the bunch centroid at $m=1$, cross-plane emittance coupling at $m=2$. A symplectic analogy relates transverse matching to longitudinal beam loading. Several phenomena common to LWFA and PWFA -- hose instabilities, pulse-front-tilt jitter, spot-asymmetry emittance growth, polarisation-dependent centroid motion, resonant cross-plane mixing -- populate the two lowest non-trivial $m$-channels and admit a unified discussion. The positron-witness problem reorganises in the same language: each known mitigation abandons one specific feature of the uniform-density blowout, drawn from a finite set. The classification also raises the possibility of an $m=3$ response channel whose magnitude remains open. We note the connection to symmetry-equivariant Bayesian optimisation of plasma accelerators.

2606.18838 2026-06-18 physics.flu-dyn 新提交

On the governing mechanism of unsteadiness in bow shock-induced three-dimensional separation

弓形激波诱导三维分离的非定常性主导机制研究

S. Vayala, K. Ramachandra, K. Abhishek, N. R. Vadlamani, R. Sriram

AI总结 通过风洞实验和数值模拟,研究凸起物引起的弓形激波-湍流边界层相互作用中低频非定常性的驱动机制,发现分离长度是关键参数,并揭示激波运动受再附着区质量注入与马蹄涡核心展向质量输运之间的不平衡和时间延迟控制。

Comments 47 pages, 38 figures. Submitted to the journal for review

详情
AI中文摘要

我们研究了凸起物引起的弓形激波-湍流边界层相互作用中低频非定常性的驱动机制。在自由流马赫数2.87下进行了风洞实验,使用了不同形状和尺寸的凸起物。通过时间分辨的表面压力测量和纹影成像,非定常性表现为低频激波振荡,基于边界层厚度($\delta$)的斯特劳哈尔数为$St_{\delta}\sim 0.01$,而分离区域主要表现为中频压力振荡,$St_{\delta} \sim 0.1$。中跨分离长度$L_{sep}$被确定为决定激波振荡时间和长度尺度的关键参数。通过可压缩自适应分离涡模拟对一种特定情况(即边长15 mm的立方体凸起物)进行了相互作用的进一步细节研究。利用计算得到的3D数据,采用本征正交分解(POD)进行了详细的模态分析。激波足在中跨附近的拍动明显,除了相干的前后振荡外,壁面压力脉动的POD中反对称模态占主导。激波足的运动从中跨附近开始,而其他展向位置的激波足则滞后。拍动和非对称性与回流区的展向范围有关。利用低频模态重建的3D流场,结合两点相关性的佐证,推断再附着处注入分离区的质量与马蹄涡核心处展向离开的质量之间的不平衡和时间延迟控制了观察到的激波运动。

英文摘要

We investigate the driving mechanism of low-frequency unsteadiness in bow shock-turbulent boundary layer interactions due to protuberances. Wind tunnel experiments are conducted at a freestream Mach number of 2.87 with protuberances of different shapes and sizes. From time-resolved surface pressure measurements and schlieren imaging, the unsteadiness is characterized by low-frequency shock oscillations, with a Strouhal number of $St_δ\sim 0.01$ based on the boundary layer thickness ($δ$), while the separated region exhibits predominantly mid-frequency pressure oscillations, with $St_δ \sim 0.1$. Mid-span separation length, $L_{sep}$, is identified as a key parameter in determining time and length scales of shock oscillations. Further details of the interaction are examined through compressible adaptive detached eddy simulations for one particular case, viz.,the cubical protuberance of side 15 mm. A detailed modal analysis using proper orthogonal decomposition (POD) is performed with the 3-D data from computations. Flapping of shock-foot about mid-span was apparent, over and above the coherent to-and-fro oscillations, with the dominance of anti-symmetric mode in the POD of wall pressure fluctuations. The motion of the shock foot is initiated near mid-span, while the shock foot at other spanwise locations lags behind. The flap and asymmetries are related to the spanwise extent of reverse flow. From the reconstructed 3-D flow field using low-frequency modes, along with corroborating observations from the two-point correlations, it is inferred that the imbalance and time lag between the mass injected into the separated region at reattachment and the mass leaving spanwise at the horseshoe vortex core govern the observed shock motion.

2606.18813 2026-06-18 physics.optics 新提交

Magnetic-polarization-dependent spectroscopy of lanthanide-doped anisotropic crystals

镧系掺杂各向异性晶体的磁极化相关光谱

Zoe Liestmann, Luca Koldeweyh, Moritz Badtke, Sascha Kalusniak, Christian Kränkel, Hiroki Tanaka

AI总结 实验证明镧系掺杂各向异性晶体的吸收和发射光谱存在显著的磁极化依赖性,需引入第三种偏振(α偏振)进行完整表征。

Comments 18 pages, 11 figures, 7 tables

详情
AI中文摘要

我们实验证明,三价镧系掺杂各向异性晶体的吸收和发射光谱可以表现出显著的磁极化依赖性,这在迄今为止的光谱研究中很大程度上被忽视了。聚焦于掺杂Yb3+、Tm3+、Er3+和Ho3+的单轴激光基质LiYF4 (YLF),我们测量了理论上预测具有强磁偶极贡献的跃迁的磁极化相关吸收和发射光谱。我们的结果表明,即使在这些成熟的激光材料中,也存在磁偶极诱导的光谱各向异性,即相同电场取向但不同磁场取向下的光谱差异。单轴晶体的完整光谱表征需要三种偏振,包括α偏振,其中电场矢量E和磁场矢量H都垂直于c轴(E ⊥ c, H ⊥ c),以及常用的两种偏振π(E ∥ c, H ⊥ c)和σ(E ⊥ c, H ∥ c)。我们进一步讨论了观察到的磁偶极诱导光谱各向异性和计算的磁偶极分支比、各向异性对发射截面计算的影响,以及我们的结果对其他单轴和双轴晶体的相关性。

英文摘要

We experimentally demonstrate that absorption and emission spectra of trivalent lanthanide-doped anisotropic crystals can exhibit a significant magnetic-polarization dependence, which has been largely overlooked in spectroscopic studies to date. Focusing on the uniaxial laser host LiYF4 (YLF) doped with Yb3+, Tm3+, Er3+, and Ho3+, we measure magnetic-polarization-dependent absorption and emission spectra for transitions with strong magnetic-dipole (MD) contributions predicted by theory. Our results reveal that MD-induced spectral anisotropy, i.e., spectral differences for the same electric field orientation but for different magnetic field orientations, is present even in these well-established laser materials. A complete spectroscopic characterization of uniaxial crystals requires three polarizations, including the $α$-polarization, with both the electric field vector E and the magnetic field vector H perpendicular to the c-axis (E $\perp$ c, H $\perp$ c), in addition to the commonly used two polarizations $π$ (E $\parallel$ c, H $\perp$ c) and $σ$ (E $\perp$ c, H $\parallel$ c). We further discuss the observed MD-induced spectral anisotropy and calculated MD branching ratios, the impact of the anisotropy on emission cross-section calculations, and the relevance of our results to other uniaxial and biaxial crystals.

2606.18784 2026-06-18 physics.optics 新提交

Volumetric nanoscale localization using engineered point spread functions in light sheet microscopy

利用光片显微镜中的工程点扩散函数实现体积纳米级定位

R. E. Bautista Gonzalez, R. Mouthaan, A. Upadhya, D. J. X. Chow, K. R. Dunning, K. Dholakia

AI总结 结合双艾里工程点扩散函数与双光子光片荧光显微镜,实现大体积三维纳米级定位,横向精度<20 nm、轴向42 nm,并有望在毫米级样本中达到亚10 nm。

详情
AI中文摘要

在光学显微镜中,跨越大生物体积的纳米级三维定位仍然是一个突出的挑战,现有方法通常受限于成像速度、体积视场和定位精度,难以同时满足。在这里,我们通过将双艾里工程点扩散函数与双光子光片荧光显微镜相结合,克服了这些限制,实现了在整个大体积视场中的纳米级定位。我们的框架明确考虑了生物荧光团的宽带荧光发射特性,确保了在真实成像条件下的准确定位。我们在295 μm x 330 μm x 100 μm的体积上实现了横向<20 nm、轴向42 nm的定位精度,并有望在毫米级样本中实现亚10 nm定位。在荧光珠模型和活体哺乳动物卵母细胞中的实验证实了在受控和生物复杂环境中的稳健性能。这些结果为基于定位的超分辨率成像在生物相关体积上的可扩展策略奠定了基础,弥合了纳米级精度与大体积显微成像之间的差距。

英文摘要

Nanoscale three-dimensional localization across large biological volumes remains an outstanding challenge in optical microscopy, with existing approaches typically limited by imaging speed, volumetric field of view and localization precision when required simultaneously. Here, we overcome these limitations by combining a twin Airy engineered point spread function with two-photon light sheet fluorescence microscopy, enabling nanoscale localization throughout large volumetric fields of view. Our framework explicitly incorporates the broadband fluorescence emission characteristic of biological fluorophores, ensuring accurate localization under realistic imaging conditions. We achieve localization precisions of $<20$~nm laterally and 42~nm axially over volumes measuring 295~$μ$m x 330~$μ$m x 100~$μ$m , with a projected path to sub-10-nm localization in millimeter-scale specimens. Experiments in fluorescent bead phantoms and live mammalian oocytes confirm robust performance in both controlled and biologically complex environments. These results establish a scalable strategy for localization-based super-resolution imaging across biologically relevant volumes, bridging the gap between nanoscale precision and large-scale volumetric microscopy.

2606.18760 2026-06-18 physics.chem-ph 新提交

Giant Nonequilibrium Fluctuations at a Reactive Surface

反应表面上的巨大非平衡涨落

Hyun Tae Jung, Hyungjun Kim, Alejandro L. Garcia, Andrew J. Nonaka, John B. Bell, Ishan Srivastava, Changho Kim

AI总结 通过最小异质催化反应器模拟,发现气体中的巨大涨落可在接触的反应表面上诱导出微米尺度的空间相关涨落,源于吸附速率对分压的依赖。

详情
AI中文摘要

我们研究气体中的巨大涨落是否能在与气体接触的反应表面上诱导出相应的涨落。对最小异质催化反应器的数值模拟表明,这种涨落确实在表面上出现,空间相关性延伸至微米尺度。这些涨落源于吸附速率对反应物分压的依赖。因此,表面覆盖结构因子与分压的结构因子相似,在波数范围内表现出类似的增强和滚降行为。

英文摘要

We investigate whether giant fluctuations in a gas can induce corresponding fluctuations on a reactive surface in contact with the gas. Numerical simulations of a minimal heterogeneous catalytic reactor demonstrate that such fluctuations indeed emerge on the surface, with spatial correlations extending over micrometer scales. These fluctuations originate from the dependence of the adsorption rate on the reactant partial pressure. As a result, the surface-coverage structure factor mirrors that of the partial pressure, exhibiting similar enhancement and roll-off behavior across wave numbers.

2606.18745 2026-06-18 physics.comp-ph physics.plasm-ph 新提交

Extension of a multi-region free-surface MHD solver beyond the inductionless approximation

多区域自由表面MHD求解器超越无感应近似的扩展

Min Ki Jung, Brian Wynne, Francisco Saenz, Yufan Xu, Jabir Al-Salami, Yong-Su Na, Egemen Kolemen

AI总结 将开源求解器FreeMHD扩展至无感应近似之外,采用矢量势公式自洽求解感应磁场,并通过解析解和实验验证,为有限磁雷诺数条件下的聚变事件建模奠定基础。

详情
AI中文摘要

自由表面液态金属流是未来聚变反应堆面向等离子体组件的主要候选方案。现有的瞬态三维自由表面MHD求解器依赖于无感应近似,即忽略感应磁场。本文将开源求解器FreeMHD [B. Wynne et al., Phys. Plasmas 32, 013907 (2025)] 扩展到无感应近似之外,使用矢量势公式自洽地求解感应磁场,该公式通过构造强制满足$\nabla\cdot\boldsymbol{B}=0$,同时保留原始的多区域、两相框架。该求解器在多个哈特曼数范围内针对解析的Shercliff和Hunt管道流解进行了验证,并通过LMX-U实验的自由表面高度测量进行了验证。据我们所知,FreeMHD2是首个经过实验验证的开源自由表面液态金属求解器,能够在不采用无感应近似的情况下解析感应磁场的演化。通过移除而非放宽该近似,该公式为未来模拟大规模瞬态聚变事件中预期的有限磁雷诺数条件提供了基础。

英文摘要

Free-surface liquid metal flows are a leading candidate for the plasma-facing components of future fusion reactors. Existing transient, three-dimensional, free-surface MHD solvers rely on the inductionless approximation in which the induced magnetic field is neglected. This paper extends the open-source solver FreeMHD [B. Wynne et al., Phys. Plasmas 32, 013907 (2025)] beyond the inductionless approximation to resolve the induced magnetic field self-consistently using a vector-potential formulation that enforces $\nabla\cdot\boldsymbol{B}=0$ by construction while preserving the original multi-region, two-phase framework. The solver is verified against analytical Shercliff and Hunt duct-flow solutions across a range of Hartmann numbers and validated against free-surface height measurements from the LMX-U experiment. To the best of our knowledge, FreeMHD2 is the first open-source, experimentally validated free-surface liquid metal solver to resolve the evolution of the induced magnetic field without invoking the inductionless approximation. By removing this approximation rather than relaxing it, the formulation provides the basis for future modeling of the finite magnetic Reynolds number conditions expected in large-scale, transient fusion events.

2606.18711 2026-06-18 physics.optics quant-ph 新提交

Integration of diamond nanobeams with SnVs on Al2O3 waveguides for scalable quantum photonic chip application

用于可扩展量子光子芯片应用的SnV金刚石纳米梁与Al2O3波导的集成

Yeting Yang, Ryota Kitagawa, Tetsuya Miyatake, Masaharu Hida, Naoki Fushimi, Koki Kaminaka, Takuto Yamaguchi, Toshiki Iwai, Itsuki Takagi, Hidetsugu Matsukiyo, Satomi Ishida, Satoshi Iwamoto, Manabu Ohtomo, Toshiyuki Miyazawa, Kenichi Kawaguchi, Ryoichi Ishihara, Shintaro Sato

AI总结 本文通过双层制造工艺,将含SnV色心的金刚石纳米梁与Al2O3波导集成,实现了光学耦合,并观察到导出的SnV-发射,展示了可扩展的集成方法。

Comments 12 pages, 3 figures, submissted to JJAP

详情
AI中文摘要

金刚石中的锡空位(SnV)中心是集成量子光子学中有前途的固态量子比特。在这里,我们制造并表征了一种包含SnV中心的Al2O3双锥波导结构上的金刚石,展示了金刚石纳米梁与底层Al2O3波导之间的光学耦合。这些器件采用与晶圆级光刻兼容的双层制造方法实现。在所有光学活性器件中观察到清晰的导出的SnV-发射,表明集成结构中有效的光学耦合。这些结果展示了一种可扩展的制造方法,用于将金刚石色心与光子波导集成。

英文摘要

Tin vacancy (SnV) centers in diamond are promising solid state qubits for integrated quantum photonics. Here, we fabricate and characterize a diamond on Al2O3 dual taper waveguide structure containing SnV centers, demonstrating optical coupling between the diamond nanobeam and the underlying Al2O3 waveguide. The devices are realized using a bilayer fabrication approach compatible with wafer scale lithography. Clear guided SnV- emission is observed in all optically active devices, indicating effective optical coupling in the integrated structure. These results demonstrate a scalable fabrication approach toward integrating diamond color centers with photonic waveguides.

2606.18670 2026-06-18 physics.app-ph 新提交

Unified 1D Theory and Design Principles for Harmonic Electrothermal Characterization of Nanoscale Conductors

纳米导体谐波电热表征的统一一维理论与设计原理

Chuyue Peng, Joshua Ginzburg, Annika Shah, Matthias Kuehne

AI总结 提出统一理论桥接悬浮与基底支撑导体两种实验几何,通过统一热传递函数预测各谐波电压响应,并建立纳米导体表征的设计原理。

详情
AI中文摘要

基于交流焦耳加热电流的第三或其他谐波的电热表征被广泛用于固体导体及其环境(包括固体基底和流体)的热分析。然而,一种桥接两种典型实验几何——悬浮导体与基底支撑导体——中传热的统一理论一直缺失。这里,我们提出并验证了这样一个理论,它通过统一的热传递函数显式地考虑了有限导体长度、热质量和环境耦合。该框架能够预测驱动电流所有谐波(直流、1ω、2ω、3ω)下的电压响应,并制定纳米导体表征的设计原理。导体长度l是控制导体热质量主导热响应的频率范围的主要参数,其特征频率ω_c=α/l^2,其中α是导体的热扩散率——与先前报道的没有环境耦合的悬浮线的判据密切相关。我们的统一框架推广了这一结果,揭示了足够弱的环境耦合是ω_c控制热质量主导响应开始的必要条件。优化界面热阻和环境热阻抗可以进一步提高温度分辨率并促进在基底上的实现。

英文摘要

Electrothermal characterization based on the third or other harmonics of an ac Joule heating current is widely deployed for the thermal analysis of solid conductors and their environment, including solid substrates and fluids. However, a unified theory that bridges heat transfer in two archetypal experimental geometries - suspended vs. substrate-supported conductor - has been missing. Here, we present and validate such a theory that explicitly accounts for finite conductor length, thermal mass, and environmental coupling through a unified thermal transfer function. This framework enables the prediction of voltage responses at all harmonics of the driving current (dc, 1$ω$, 2$ω$, 3$ω$) and the formulation of design principles for the characterization of nanoscale conductors. The conductor length $l$ is the primary parameter controlling the frequency regime at which the conductor's thermal mass dominates the thermal response, with the characteristic frequency $ω_\mathrm{c}=α/l^2$, where $α$ is the conductor's thermal diffusivity - closely related to a criterion previously reported for suspended wires free from environmental coupling. Our unified framework generalizes this result, revealing that sufficiently weak environmental coupling is a necessary condition for $ω_\mathrm{c}$ to govern the onset of thermal-mass-dominated response. Optimization of interfacial thermal resistance and environmental thermal impedance may further improve temperature resolution and facilitate on-substrate implementations.

2606.18648 2026-06-18 physics.comp-ph 新提交

Deep Research in Physical Sciences: A Multi-Agent Framework and Comprehensive Benchmark

物理科学中的深度研究:多智能体框架与综合基准

Yigeng Jiang, Tengchao Yang, Taoyong Cui, Jiaxing Wan, Yuan Wang, Weida Wang, Zhiyu Liu, Chuyi Peng, Binzhao Luo, Maoli Gao, Huaihai Huang, Yuqianer Zeng, Ziyang Zheng, Dongchen Huang, Chao Chen, Zichao Liu, Weiping Shen, Shuchen Pu, Siyu Zhou, Runmin Ma, Yusong Hu, Fei Chao, Bo Zhang, Xiawu Zheng, Zifu Wang, Lei Bai, Yunqi Cai, Shufei Zhang

AI总结 提出PhySciBench基准评估LLM在物理科学中的深度研究能力,并开发DelveAgent多智能体框架,通过自适应规划、双粒度记忆和分层反思机制提升准确率并降低推理成本。

Comments 19 pages, 5 figures, 1 table;

详情
AI中文摘要

深度研究智能体是基于大型语言模型(LLM)的系统,专为自主、多步骤的科学推理而设计,在加速物理科学研究方面具有巨大潜力。然而,目前缺乏对其在该领域能力的全面深入评估。为填补这一空白,我们引入了PhySciBench,一个与物理科学研究高度相关的基准,包含200个专家策划的问题,涵盖物理和化学,分布在反映真实科学工作流程的六个任务类别中。对最先进模型和智能体系统在PhySciBench上的评估显示性能有限;即使是最强的基线Gemini Deep Research,准确率也仅为33.5%。对失败案例的分析发现了三个反复出现的缺陷:扩展推理链的脆弱性、跨步骤的知识迁移有限以及缺乏基于物理的自验证。受这些发现启发,我们开发了DelveAgent,一个模块化的多智能体框架,配备自适应规划循环、双粒度记忆和分层物理接地反思机制。在四个科学基准上,DelveAgent将准确率提高了最多7.5个百分点,同时将推理成本降低到最强基线的大约三分之一。这些结果确立了PhySciBench作为评估物理科学中AI系统关键基准的重要性,并表明架构专业化可以有效增强自主科学研究的可靠性。

英文摘要

Deep research agents are Large Language Model (LLM)-based systems designed for autonomous, multi-step scientific reasoning, and they hold immense potential for accelerating research in the physical sciences. However, comprehensive and in-depth evaluations of their capabilities within this domain remain lacking. To address this gap, we introduce PhySciBench, a benchmark highly relevant to physical science research, comprising 200 expert-curated questions, balanced between physics and chemistry, across six task categories that reflect real-world scientific workflows. Evaluations of state-of-the-art models and agent systems on PhySciBench reveal limited performance; even the strongest baseline, Gemini Deep Research, achieves an accuracy of only 33.5%. Analysis of failure cases identifies three recurrent deficiencies: fragility in extended reasoning chains, limited knowledge transfer across steps, and a lack of physics-grounded self-verification. Motivated by these findings, we develop DelveAgent, a modular multi-agent framework equipped with an adaptive planning loop, dual-granularity memory, and a hierarchical physics-grounded reflection mechanism. Across four scientific benchmarks, DelveAgent improves accuracy by up to 7.5 percentage points while reducing inference costs to approximately one-third of the strongest baseline. These results establish the significance of PhySciBench as a critical benchmark for evaluating AI systems in the physical sciences and demonstrate that architectural specialization can effectively enhance the reliability of autonomous scientific research.

2606.18604 2026-06-18 physics.bio-ph 新提交

A symmetric relaxation method for entire two-dimensional cellular networks and its implications

整个二维细胞网络的对称松弛方法及其意义

Kai Xu, Lifan Weng, Zihan Wang, Yuyang Lian, Bin Huang

AI总结 提出一种适用于内部和边缘顶点的对称松弛方法,模拟二维细胞网络松弛,验证了von Neumann-Mullins定律等,并揭示了对称松弛通过减少短边抑制T1拓扑转变。

详情
AI中文摘要

为了模拟整个二维细胞网络的松弛,本研究提出了一种适用于内部和边缘顶点的对称松弛方法。这两类顶点的松弛由相关细胞的中心角对称性和每个顶点的角度对称性决定,但主要考虑因素不同。使用具有不同不规则性的修剪Voronoi网络作为松弛模拟的初始网络。特别地,我们提出了一种正六边形无序化方法来生成Voronoi网络,并发现不规则性值为1的网络内部细胞表现出保守的边数分布,正如在其他二维细胞网络中发现的那样。模拟结果对内部和边缘细胞均符合von Neumann-Mullins定律,并且包含几何修正项的修正方程显著提高了预测质量。还再现了Aboav-Weaire定律和Lewis定律,其中后者显示松弛细胞趋向于椭圆的极大内接多边形。对边长、内角和形状指数的分析表明,对称松弛通过减少短边同时增加相邻细胞间的面积差异来抑制T1(邻居交换)拓扑转变。研究结果表明,当力不平衡克服对称松弛的稳定效应时,可能触发T1事件,这为二维泡沫中的T1提供了可能的机制解释。

英文摘要

To simulate the relaxation of an entire 2D cellular network, this study proposes a symmetric relaxation method for both inner and marginal vertices. The relaxations of these two types of vertices are determined by the central angle symmetry of associated cells and the angle symmetry at each vertex, but with different major considerations. Trimmed Voronoi networks with varying irregularity are used as initial networks for the relaxation simulation. In particular, we propose a regular hexagon disordering method to generate Voronoi networks and find that the inner cells of networks with an irregularity value of one exhibit a conserved edge number distribution, as found in other 2D cellular networks. Simulation results agree with the von Neumann-Mullins law for both inner and marginal cells, and a modified equation including a geometric correction term significantly improves prediction quality. The Aboav-Weaire law and Lewis law are also reproduced, with the latter showing that relaxed cells tend to approach the ellipses' maximum inscribed polygons. Analysis of edge length, interior angle, and shape index reveals that symmetric relaxation inhibits T1 (neighbour exchange) topological transitions by reducing short edges while increasing area disparity among neighbouring cells. The findings suggest that T1 events may be triggered when force disequilibrium overcomes the stabilising effect of symmetric relaxation, providing a possible mechanistic explanation for T1 in 2D foams.

2606.18602 2026-06-18 physics.flu-dyn 新提交

Response of a Turbulent Boundary Layer to a Synthetic Periodic Large-Scale Structure

湍流边界层对合成周期性大尺度结构的响应

Mitchell Lozier, Flint O. Thomas, Stanislav Gordeyev

AI总结 实验研究零压力梯度湍流边界层对外区大尺度扰动的动态响应,利用等离子体致动器引入合成大尺度结构,揭示其对近壁湍流调制的“自上而下”相互作用机制。

详情
AI中文摘要

实验研究了零压力梯度湍流边界层(TBL)对外区大尺度扰动的动态响应。基线TBL具有中等雷诺数,因此不存在自然产生的有能量的大尺度结构(LSS)。然后,在TBL的外区放置一个主动等离子体致动器,以引入周期性的、展向均匀的合成LSS。这种新颖的致动方案提供了一种新工具,用于实验检验TBL动力学/相互作用的“自上而下”观点。通过结合平面粒子成像测速和展向偏移热线,在致动器下游的大流向范围内研究了TBL对该合成结构的响应。实施锁相分析以分离和测量由该合成LSS引起的大尺度运动的流向发展和湍流振幅的变化。在近壁处的大尺度运动(由合成LSS线性叠加)与湍流振幅的周期性调制之间观察到强相关性。发现这种周期性调制与由诱导大尺度运动驱动的湍流产生和输运的相位相关变化有关。这些诱导大尺度运动的相速度,结合近壁处展向相干性的间歇变化,揭示了合成LSS对近壁循环动力学的额外但瞬态的影响。总体而言,这些结果表征了自上而下相互作用对全局TBL动力学的影响和局限性。

英文摘要

The dynamic response of a zero-pressure gradient turbulent boundary layer (TBL) to a large-scale perturbation in the outer region was investigated experimentally. The baseline TBL had a moderate Reynolds number such that there was no naturally occurring energetic large-scale structure (LSS) present. An active plasma-based actuator was then placed in the outer region of the TBL to introduce a periodic, spanwise-uniform, synthetic LSS. This novel actuation scheme provides a new tool by which to experimentally examine the `top-down' view of TBL dynamics/interactions. The TBL response to this synthetic structure was investigated using a combination of planar particle imaging velocimetry and spanwise offset hot-wires, over a large streamwise extent downstream of the actuator device. Phase-locked analysis was implemented to isolate and measure the streamwise development of large-scale motions and changes in turbulence amplitude induced by this synthetic LSS. A strong correlation was observed between large-scale motions near the wall, linearly superimposed from the synthetic LSS, and a periodic modulation of turbulence amplitudes. This periodic modulation was found to be linked to phase-dependent changes in both the production and transport of turbulence driven by the induced large-scale motions. The phase speed of these induced large-scale motions, coupled with intermittent changes to spanwise coherence near the wall, revealed an additional, but transient, effect of the synthetic LSS on near-wall cycle dynamics. Overall, these results characterize the influences, and limitations, of top-down interactions on global TBL dynamics.

2606.18570 2026-06-18 physics.chem-ph 新提交

Streamlining Analysis and Design of Two-Dimensional Electronic Spectroscopy using Machine Learning

利用机器学习简化二维电子光谱的分析与设计

Nicholas I. Hausman, Joseph Kelly, Michael S. Chen, Frank Hu, Angela Lee, Andrés Montoya-Castillo, Gabriela S. Schlau-Cohen, Thomas E. Markland

AI总结 提出基于高斯混合模型的机器学习框架,从有限或噪声的2DES数据中提取振动耦合信息,外推光谱至未测量时间延迟,并指导额外实验选择以提升精度。

Comments 28 pages, 16 figures

详情
AI中文摘要

二维电子光谱(2DES)提供了电子与核运动及动力学之间耦合的独特见解,使其成为材料科学和生物学等多个领域的关键技术。获取2DES数据需要一系列涉及多个脉冲的测量来构建完整图像——这是一项耗时的任务,通常需要在有限或噪声数据下工作。这里我们介绍一个基于机器学习的框架,旨在最大化从2DES实验中提取的数据,并为选择额外实验提供指导。我们设计了一个高斯混合模型来学习系统的潜在光谱密度,从而提取振动耦合并将2DES光谱外推到超出测量范围的其他时间延迟,并展示了我们的框架如何用于选择额外的测量以进一步提高精度。我们表明,我们的方法在多种系统上都能产生准确的结果,包括从气相中的光活性黄色蛋白到苯中的尼罗红再到水中的阴离子绿色荧光蛋白发色团的模拟,以及乙醇中尼罗蓝的实验。我们的工作提供了一条高效途径,以最小的实验成本从2DES中获取最大信息。

英文摘要

Two-dimensional electronic spectroscopy (2DES) offers unique insights into the coupling between electronic and nuclear motion and dynamics, making it a key technique in diverse fields, including materials science and biology. Obtaining 2DES data requires a series of measurements that involve multiple pulses to construct the full picture - a time-consuming task that often necessitates working with limited or noisy data. Here we introduce a machine-learning based framework that aims to maximize the data that can be extracted from 2DES experiments and provides guidance towards the selection of additional experiments. We design a Gaussian mixture model to learn the underlying spectral density of a system, allowing the extraction of vibronic couplings and the extrapolation of the 2DES spectra to other time delays beyond those measured, and demonstrate how our framework can be used to select additional measurements to further improve the accuracy. We show that our approach yields accurate results on a variety of systems, including simulations ranging from photoactive yellow protein in the gas phase to Nile red in benzene to the anionic green fluorescent protein chromophore in water, and experiments on Nile blue in ethanol. Our work provides an efficient route to extract maximum insights from 2DES while incurring minimal experimental costs.

2606.18522 2026-06-18 physics.app-ph quant-ph 新提交

Piezoelectric resonators in thin-film barium titanate from room temperature to millikelvin

从室温到毫开尔文的钛酸钡薄膜压电谐振器

Hao Tian, Shu-Yuan Chang, Nuha Akhtar, Kasra Sardashti, Mohammad Mirhosseini

AI总结 本研究制备并表征了薄膜钛酸钡上的声表面波谐振器,展示了高机电耦合系数和低电压快速开关能力,并在毫开尔文温度下观察到压电响应,为量子电路中的压电耦合提供了潜力。

详情
AI中文摘要

铁电材料具有强非线性,是射频信号处理、光通信和新兴量子系统等关键技术的基础。钛酸钡(BTO)是一个显著的例子,它结合了强压电和电光响应。虽然块体BTO已被研究数十年,但其最近可用的薄膜的压电性质以及在量子硬件相关的毫开尔文温度下的行为仍基本未被探索。在这里,我们在薄膜BTO上制备并表征了声表面波(SAW)谐振器。测量到的器件表现出高机电耦合(在5.2 GHz时k2eff为0.14),并工作至7.8 GHz。通过这些测量,结合多畴微结构的有限元建模,我们提取了有效压电系数d33eff为53 pC/N,与块体BTO相当。利用固有的铁电性,我们进一步展示了低电压快速(100 ns)开关,这对于可重构射频前端和参量放大器具有吸引力。将这些测量扩展到毫开尔文温度,我们发现压电响应持续存在,d33eff为19 pC/N,表明BTO在超导量子电路中用于压电耦合的潜力。这些结果将薄膜BTO定位为经典和量子信息技术中一个有前景的压电平台。

英文摘要

Ferroelectric materials, with their strong nonlinearities, underpin key technologies across radio-frequency (RF) signal processing, optical communications, and emerging quantum systems. Barium titanate (BTO) is a notable example, combining strong piezoelectric and electro-optic responses. While bulk BTO has been studied for decades, the piezoelectric properties of its recently available thin films, and their behavior at the millikelvin temperatures relevant to quantum hardware, remain largely unexplored. Here, we fabricate and characterize surface acoustic wave (SAW) resonators on thin-film BTO. The measured devices exhibit high electromechanical coupling (k2eff 0.14 at 5.2 GHz) and operate up to 7.8 GHz. From these measurements, combined with finite-element modeling of the multi-domain microstructure, we extract an effective piezoelectric coefficient d33eff of 53 pC/N, comparable to bulk BTO. Exploiting the intrinsic ferroelectricity, we further demonstrate low-voltage switching with a fast (100 ns) response, attractive for reconfigurable RF front-ends and parametric amplifiers. Extending these measurements to millikelvin temperatures, we find that the piezoelectric response persists, with d33eff 19 pC/N, pointing to the potential of BTO for piezoelectric coupling in superconducting quantum circuits. These results position thin-film BTO as a promising piezoelectric platform for both classical and quantum information technologies.

2606.18499 2026-06-18 physics.flu-dyn 新提交

Solution of the Newtonian plane Couette flow with dynamic wall slip using machine-learning methods

利用机器学习方法求解具有动态壁面滑移的牛顿平面库埃特流

Georgia Foutsitzi, Nikolaos Antoniadis, Georgios C. Georgiou

AI总结 比较物理信息神经网络(PINNs)和数据驱动深度算子网络(DeepONets)预测动态壁面滑移的牛顿平面库埃特流,DeepONet实现近实时推理,加速比达540倍。

Comments 25 pages, 11 figures, 3 tables

详情
AI中文摘要

本研究对物理信息神经网络(PINNs)和数据驱动深度算子网络(DeepONets)在预测具有动态壁面滑移的牛顿平面库埃特流演化方面进行了比较研究。虽然传统数值方法(如Crank-Nicolson格式)具有高精度,但其计算需求在实时应用中带来挑战。为此,我们首先实现PINN框架来求解特定物理参数的控制方程。随后,我们开发了一个数据驱动的DeepONet,在高保真数值数据上训练,以学习跨越广泛滑移边界条件和上壁速度的连续解算子。我们的结果表明,尽管PINN实现了优越的点精度(相对L_2误差为0.083%),但它仍然受限于需要针对特定实例重新训练。相比之下,DeepONet在未见和分布外信号上表现出稳健的泛化能力,平均相对误差分别为0.36%和0.88%。最值得注意的是,它提供了近乎瞬时的推理,相对于数值求解器实现了约540倍的加速比,相对于PINN实现了30.5%的加速比。这项工作展示了基于物理和数据驱动架构的协同作用,并将DeepONet确立为用于快速参数探索和实时流体动力学预测的高效替代模型。

英文摘要

This study presents a comparative investigation of Physics-Informed Neural Networks (PINNs) and data-driven Deep Operator Networks (DeepONets) for predicting the evolution of plane Newtonian Couette flow with dynamic wall slip. While traditional numerical methods, such as the Crank-Nicolson scheme, offer high accuracy, their computational demand poses challenges in real-time applications. To address this, we first implement a PINN framework to solve the governing equations for specific physical parameters. Subsequently, we develop a data-driven DeepONet, trained on high-fidelity numerical data, to learn the continuous solution operator across a broad range of slip boundary conditions and upper wall velocities. Our results indicate that while the PINN achieved superior point-wise precision with a relative L_2 error of 0.083%, it remains constrained by the requirement for instance-specific retraining. In contrast, the DeepONet demonstrates robust generalization on unseen and out-of-distribution signals with a mean relative error of 0.36% and 0.88%, respectively. Most notably, it provides near-instantaneous inference, achieving a speedup factor of approximately 540X over the numerical solver and 30.5% over the PINN. This work demonstrates the synergy between physics-based and data-driven architectures and establishes DeepONet as a highly efficient surrogate model for rapid parametric exploration and real-time fluid dynamics forecasting.

2606.18495 2026-06-18 physics.chem-ph physics.bio-ph physics.comp-ph q-bio.BM 新提交

Bayesian Sampling of Structural Ensembles: The Role of Ensemble-Counting Measures

结构系综的贝叶斯采样:系综计数测度的作用

Ivan Gilardoni, Giovanni Bussi

AI总结 本文提出Jeffreys测度作为系综计数测度,解决BELT框架中拉格朗日乘子空间平直测度导致的有限参考轨迹下后验分布不可归一化问题,并在RNA寡聚体模拟中验证了测度选择对贝叶斯估计的影响。

详情
AI中文摘要

结构系综精修被广泛用于将分子模拟与实验测量相结合。虽然大多数应用关注最大后验(MAP)系综,但后验分布的贝叶斯采样可以为任意可观测量提供不确定性估计和后验平均值。贝叶斯能量景观倾斜(BELT)框架引入了这一方向的一个显著步骤,其中对由拉格朗日乘子参数化的最大熵系综族进行采样。这里,我们表明在这种设置下,贝叶斯采样需要显式选择系综计数测度。特别是,原始BELT公式中使用的拉格朗日乘子空间的平直测度导致后验分布对于有限参考轨迹在形式上不可归一化。我们提出Jeffreys测度作为一种不变的系综计数处方,恢复了此处考虑的有限样本情况下的可归一化性,并为后验平均值提供了一致的定义。使用解析可处理的高斯模型和RNA寡聚体模拟的最大熵精修,我们比较了不同的系综计数测度,并表明它们可以显著影响贝叶斯估计。所得方法已在\ exttt{MDRefine}软件包中实现。

英文摘要

Structural ensemble refinement is widely used to integrate molecular simulations with experimental measurements. While most applications focus on the maximum-a-posteriori (MAP) ensemble, Bayesian sampling of the posterior distribution can provide uncertainty estimates and posterior averages for arbitrary observables. A notable step in this direction was introduced by the Bayesian Energy Landscape Tilting (BELT) framework, where sampling is performed on a family of maximum-entropy ensembles parametrized by Lagrange multipliers. Here, we show that Bayesian sampling in this setting requires an explicit choice of ensemble-counting measure. In particular, the flat measure in Lagrange-multiplier space used in the original BELT formulation leads to a posterior distribution that is formally non-normalizable for finite reference trajectories. We propose the Jeffreys measure as an invariant ensemble-counting prescription, restoring normalizability in the finite-sample situations considered here, and providing a consistent definition of posterior averages. Using both an analytically tractable Gaussian model and maximum-entropy refinement of RNA oligomer simulations, we compare different ensemble-counting measures and show that they can significantly affect Bayesian estimates. The resulting methodology has been implemented in the \texttt{MDRefine} software package.

2606.18447 2026-06-18 physics.app-ph 新提交

Epitaxial Growth of Ultra-smooth $δ$-NbN Thin Films on TiN-Buffered Sapphire by Room-Temperature Sputtering

室温溅射在TiN缓冲蓝宝石上外延生长超光滑$\delta$-NbN薄膜

Swagata Bhunia, Aakash Shandilya, Sounak Samanta, Bikash C Barik, Soumyadip Chatterjee, Parushottam Majhi, Siddarth Rastogi, Kantimay Das Gupta, Suddhasatta Mahapatra, Apurba Laha

AI总结 本研究通过室温溅射在TiN缓冲c-蓝宝石衬底上外延生长单晶$\delta$-NbN薄膜,实现了皮米级表面粗糙度,并探讨了TiN缓冲层对超导临界温度的影响。

详情
AI中文摘要

$\delta$相氮化铌(NbN)是一种有前景的超导材料,化学性质稳定,且与常规III族氮化物半导体晶格兼容。由于高临界温度(T$_{c}$)和高临界磁场(H$_{c}$),NbN在从单光子探测器、热电子辐射热计到基于超导电路的量子计算架构等多种应用中备受青睐。然而,以经济有效的方式合成相纯和化学计量比的$\delta$-NbN高质量外延薄膜具有挑战性。在本研究中,我们研究了通过室温溅射在TiN缓冲c-蓝宝石(Al$_{2}$O$_{3}$)衬底上外延生长单晶$\delta$-NbN。对于这些薄膜,我们展示了皮米尺度的表面粗糙度,这是迄今为止报道的最低值。观察到外延$\delta$-NbN薄膜的临界温度(T$_{c}$)随着TiN缓冲层的插入而降低,初步归因于邻近效应导致的库珀对泄漏。TiN和NbN层表现为双层系统,其中由于不存在氧化物中间层,库珀对泄漏得以促进。因此,T$_{c}$随着TiN层厚度的增加而降低。

英文摘要

The $δ$ phase of Niobium Nitride (NbN) is a promising superconducting material, which is chemically stable and shares lattice compatibility with conventional III-Nitride semiconductors. Due to a high critical temperature (T$_{c}$) and a high critical (magnetic) field (H$_{c}$), NbN is much-coveted for a diverse set of applications spanning from single photon detectors, and hot-electron bolometers to quantum computing architectures using superconducting circuits. However, synthesizing high-quality epitaxial films of phase pure and stoichiometric $δ$-NbN in a cost-effective manner, is challenging. In this study, we investigate the epitaxial growth of single crystalline $δ$-NbN on TiN-buffered c-sapphire (Al$_{2}$O$_{3}$) substrates by sputtering at room temperature. For these films, we demonstrate a surface-roughness in picometer-scale, the lowest reported till date. The critical temperature (T$_{c}$) of the epitaxial $δ$-NbN films was observed to decrease with the insertion of the TiN buffer layer, tentatively attributable to the leakage of Cooper pairs, due to the proximity effect. TiN and NbN layer behave as a bilayer system, wherein Cooper-pair leakage is facilitated by the absence of any oxide interlayer. Consequently, T$_{c}$ reduces with increasing thickness of the TiN layer.

2606.18391 2026-06-18 physics.optics 新提交

Constant sensitivity birefringence metrology using vector vortex beams

利用矢量涡旋光束实现恒定灵敏度的双折射测量

Gabriela Flores-Cova, Daniel Salamanca-Roldán, Carmelo Rosales-Guzmán, Daniel F. Urrego, Juan P. Torres

AI总结 提出利用矢量涡旋光束进行双折射测量,通过量子估计理论证明相位估计灵敏度与未知相位无关,实验验证了该方法的优越性。

详情
AI中文摘要

差分干涉对比(DIC)显微镜和手性分析是两种测量双折射的成像技术,即样品在两个正交偏振上引入的相位差。传统方法使用高斯光束,并通过偏振变化推断双折射,导致相位估计灵敏度依赖于未知相位。我们展示了一种新型双折射探测器。它利用矢量涡旋光束,这是一种携带相反轨道角动量(OAM)光学模式的结构光。使用量子估计理论工具,我们证明了相位估计的灵敏度与未知相位值无关,并且在原则上可以比传统方法更好。我们通过实验验证了所提出的方案,展示了结构光在鲁棒且均匀的双折射传感中的潜力。

英文摘要

Differential Interference Contrast (DIC) microscopy and chiral analysis are two imaging techniques that measure the birefringence, i.e., the phase difference introduced by a sample on two orthogonal polarizations. Conventional approaches employ Gaussian beams and infer birefringence from polarization changes, resulting in phase-estimation sensitivities that depend on the unknown phase. We demonstrate here a new type of birefringence detector. It makes use of a vector vortex beam, a type of structured light endowed with optical modes that carry opposite orbital angular momentum (OAM). Using quantum estimation theory tools, we demonstrate that the sensitivity of phase estimation is independent of the value of the unknown phase, and can be even better, in principle, than the conventional approach. We experimentally validate the proposed scheme, demonstrating the potential of structured light for robust and uniform birefringence sensing.

2606.18368 2026-06-18 physics.atom-ph physics.ins-det 新提交

Design and Performance of a Heated Gas Injector for Producing Cold Molecular Beams

用于产生冷分子束的加热气体注入器的设计与性能

Avneesh Verma, Jack Mango, Shungo Fukaya, Arian Jadbabaie, Sepehr Ebadi, Ronald F. Garcia Ruiz, John M. Doyle

AI总结 本文设计并实现了一种加热气体注入器,将热气体直接送入低温环境,具有坚固、易安装、热隔离好等优点,并用于产生冷BaF自由基,未来将用于激光冷却含镭分子。

Comments 12 pages, 10 figures

详情
AI中文摘要

我们实现了一种将热气体直接送入低温环境的注入器装置。该注入器具有多个优点,包括坚固性、刚性、安装简便,以及在热(约300 K)铜填充线和冷(<3 K)低温缓冲气体池之间出色的热隔离。在分子精密测量实验的实际条件下,观察到池上的热负荷小于200 mW。聚酰胺-酰亚胺(PAI)管是基本的设计特征。填充线通过环氧树脂粘合到管的一端,而管的另一端通过滑配合连接到黄铜接头上,实现完全真空密封。冷却时,PAI在黄铜接头上收缩,形成低温密封。该注入器易于安装和拆卸,且刚性良好,在冷却至4 K时未观察到填充线相对于池的显著位移。我们通过将SF6通过热填充线流入池中,并将冷He缓冲气体通过单独的低温填充线流入池中,同时激光烧蚀含钡靶材,来表征注入器的性能。这产生了冷BaF自由基,并通过吸收光谱检测。该注入器设计将用于激光冷却含镭分子,如RaF和RaOH,在这些应用中,出于科学和安全原因,需要将SF6和H2O试剂密封地输送到低温缓冲气体池中。这些分子对于研究对称性破缺的核性质和寻找标准模型之外的物理特别有意义。

英文摘要

We realize an injector device that supplies warm gas directly into a cryogenic environment. This injector has several advantageous features, including robustness, rigidity, simple installation, and excellent thermal isolation between a hot ($\sim$300 K) copper fill line and a cold ($<$3 K) cryogenic buffer gas cell. Less than 200 mW heat load on the cell is observed in realistic conditions of a molecular precision measurement experiment. A polyamide-imide (PAI) tube is the essential design feature. The fill line is epoxied to one end of the tube while the other end of the tube is connected to the cell via a slip-fit onto a brass nipple, realizing a complete vacuum-tight seal. PAI contracts on the brass nipple when cooled, forming a cryogenic leak-tight seal. The injector is easily (de-)mountable and rigid, with no significant displacement of the fill line relative to the cell observed during cooldown to 4 K. We characterize injector performance by flowing into the cell $\text{SF}_6$ through the hot fill line and cold $\text{He}$ buffer gas through a separate cryogenic fill line while laser ablating a barium-containing target. This produces cold BaF free radicals, detected using absorption spectroscopy. This injector design will be employed to laser cool radium-containing molecules, such as $\text{RaF}$ and $\text{RaOH}$, where leak-tight delivery of $\text{SF}_6$ and $\text{H}_2\text{O}$ reagents into a cryogenic buffer gas cell is required for scientific and safety reasons. These molecules are of particular interest for the study of symmetry-violating nuclear properties and searches for physics beyond the Standard Model.

2606.18296 2026-06-18 physics.med-ph 新提交

AI-Driven Lumped-Element Modeling of Human Respiratory System for Studying Voice Mechanics

AI驱动的呼吸系统集总参数建模用于研究发声力学

Maruf Md Ikram, Maryam Naghibolhosseini, Mohsen Zayernouri

AI总结 提出基于物理的呼吸、发声和发音子系统模型,结合深度学习提取的声门面积波形,首次模拟发声时的呼吸动力学,预测无法直接测量的声门下压力分布。

Comments 40 pages, 18 figures

详情
AI中文摘要

开发了一个基于物理的预测模型,涵盖人类呼吸、发声和发音子系统,用于模拟语音产生。将肺、可压缩气道和声带表示为弹簧-阻尼-质量控制的活塞-气缸系统,我们的数学模型稳健地捕捉了发声期间气道的复杂动力学。研究了肺组织和可压缩气道的非线性粘弹性特性,产生了一个响应灵敏且富有表现力的基线呼吸模型,能够进一步扩展为针对呼吸和发声的患者特异性模型。随后,将所得框架与声道机械表示集成,该表示由声门面积波形(GAW)控制,GAW捕捉了持续发声期间声带的运动。GAW通过深度学习从一名正常发音参与者的喉部高速视频内窥镜数据中提取。我们的新范式超越了呼吸系统建模,实现了AI驱动的发声建模,包括声带动力学、与流动空气动力学的相互作用以及由声带振荡行为引起的流动阻力。我们的研究首次实现了发声的呼吸动力学模拟,直接推进了声门下压力分布(无法在人体中直接无创测量)、动态阻力以及发声期间能量传递机制的预测,在发声力学领域具有重要意义。

英文摘要

A predictive physics-based model of human respiratory, phonatory, and articulatory subsystems is developed to simulate voice production. Representing lungs, compressible airways, and vocal folds as spring-damper-mass controlled piston-cylinder systems, our mathematical model robustly captures the intricate dynamics of airways during phonation. The nonlinear viscoelastic properties of lung tissues and compressible airways were investigated, yielding a responsive and expressive baseline respiratory model with the capability to further extend into a patient-specific model for both respiration and phonation. The resulting framework was subsequently integrated with a mechanical representation of the vocal tract, governed by the glottal area waveform (GAW) capturing the motion of vocal folds during sustained phonation. The GAW is extracted from laryngeal high-speed videoendoscopy data of a normophonic participant using deep learning. Our novel paradigm transcends beyond modeling the respiratory system, enabling AI-driven modeling of vocalization, including vocal fold dynamics, interactions with flow aerodynamics, and flow resistances, induced by the oscillatory behavior of vocal folds. Our investigation leads to the first-ever simulation of respiratory dynamics for vocalization, directly advancing the prediction of subglottal pressure distributions, impossible to measure directly and noninvasively in humans, dynamic resistances, and energy transfer mechanisms during phonation in voice mechanics.

2606.18277 2026-06-18 physics.soc-ph q-bio.PE 新提交

Multi-network comparison of between-farm contacts for infectious disease surveillance in swine production

猪生产中用于传染病监测的场间接触的多网络比较

Jason A. Galvis, Nicolas C. Cardenas, Gustavo Machado

AI总结 通过比较11种网络类型(车辆移动、动物移动和基于距离的场间接触),发现车辆移动网络(尤其是饲料运输)连接最密集,育肥场在多个网络中充当超级传播者,不同网络识别的高风险农场集合不同,支持将多种传播途径纳入疾病监测。

详情
AI中文摘要

了解猪场如何直接和间接地相互连接对于描述传染病传播至关重要。本研究旨在描述11种网络类型中猪场的连通性,包括车辆移动(即卡车和拖车)、动物移动和基于距离的场间接触,以识别生产类型之间以及可能一致被表征为超级传播者的场之间的联系。卡车和拖车移动网络连接最为密集,尤其是饲料运输,其连接水平比猪移动和基于距离的网络高98.7%至99.7%。这些网络还表现出农场之间最高程度和频率的连接,而聚合卡车网络(包括所有卡车类型)显示出作为连接农场的桥梁的最大潜力。育肥场在所有网络中都与其他农场类型高度互联。母猪场经常被其他农场类型访问,尤其是通过饲料卡车移动,占这些连接的8.7%。我们证明,在车辆移动和邻近网络中,育肥场作为超级传播者发挥了主要作用。当比较每个网络中按超级传播者得分排名前50的农场时,基于车辆的网络显示出最高的相似性,车辆网络之间共享高达89%的排名靠前的农场。相比之下,猪移动和基于距离的网络识别出大部分不同的排名靠前的农场集合,与其他接触网络分别最多共享4%和8%。总体而言,每个网络都表现出独特的连接结构,导致不同的高风险农场集合,特别是在向种猪场潜在传播方面。这些发现支持将多种传播途径整合到疾病监测中。

英文摘要

Understanding how swine farms are interconnected, directly and indirectly, is essential to characterizing infectious disease transmission. This study aimed to describe the connectivity of swine farms across 11 network types, including vehicle movements (i.e., trucks and trailers), animal movements, and distance-based farm-to-farm contacts, to identify links among production types and farms likely to be consistently characterized as super-spreaders. Truck and trailer movement networks were the most densely connected, particularly for feed transport, showing connectivity levels between 98.7% and 99.7% higher than those of pig movement and distance-based networks. These networks also exhibited the highest degree and frequency of connections between farms, while the aggregated truck network, which included all truck types, showed the greatest potential to act as a bridge connecting farms. Finisher farms were highly interconnected with other farm types across all networks. Sow farms were frequently reached by other farm types, especially through feed truck movements, representing up to 8.7% of these links. We demonstrated that in vehicle movements and proximity networks, finisher farms played a major role as super-spreaders. When comparing the top 50 farms ranked by super-spreader score in each network, vehicle-based networks showed the highest similarity, with up to 89% of top-ranked farms shared between vehicle networks. In contrast, pig movement and distance-based networks identified largely distinct sets of top-ranked farms, sharing at most 4% and 8%, respectively, with other contact networks. Overall, each network exhibited a distinct connectivity structure, resulting in different sets of high-risk farms, particularly regarding potential transmission to breeding farms. These findings support the integration of multiple transmission pathways into disease surveillance.