物理与天体物理最新文献

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Quantum Boltzmann Dynamics and Bosonized Particle-Hole Interactions in Fermion Gases 费米子气体中的量子玻尔兹曼动力学和玻色子粒子-空穴相互作用

IF 1.2 3区物理与天体物理 Q3 PHYSICS, MATHEMATICAL

Journal of Statistical Physics

Pub Date : 2025-12-19 DOI: 10.1007/s10955-025-03557-z

Esteban Cárdenas, Thomas Chen

In this paper, we study a gas of (N gg 1 ) weakly interacting fermions. We describe the time evolution of states that are perturbations of the Fermi ball, and analyze the dynamics in particle-hole variables. Our main result states that, for small values of the coupling constant and for appropriate initial data, the effective dynamics of the momentum distribution is determined by a discrete collision operator of quantum Boltzmann form.

本文研究了(N gg 1 )弱相互作用费米子气体。我们描述了费米球微扰态的时间演化，并分析了粒子-空穴变量的动力学。我们的主要结果表明，对于较小的耦合常数值和适当的初始数据，动量分布的有效动力学由量子玻尔兹曼形式的离散碰撞算符决定。

引用次数: 0

Underwater wireless optical communication employing a laser diode source based on dense blue spectral multiplexing 水下无线光通信采用基于密集蓝光谱复用的激光二极管光源

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2025-12-19 DOI: 10.1016/j.optlastec.2025.114561

Chenhui Zhang , Chuanbin Sun , Yawei Zhang , Pengcheng Wan , Xingchen Lin , Xueliang Li , Jie Liu , Meng Xiang , Yongnian Huang , Hongbo Zhu , Lijun Wang

The range of blue light has been established as a suitable spectrum for underwater wireless optical communication (UWOC) thanks to its exceptional transmissivity in the underwater environments. In this work, a laser diode (LD) source based on dense blue spectral multiplexing (DBSM) with 405 nm, 450 nm and 488 nm is proposed, which can achieve a transmission capacity of 18 Gbps by employing a 16-quadrature amplitude modulation discrete multitone modulation (16-QAM DMT) in a 2.4 m underwater link. Each of the three-wavelength LDs supports a data rate of up to 6 Gbps with corresponding bit error rates (BERs) of 3.53 × 10^-3, 3.49 × 10^-3 and 3.34 × 10^-3, all of which are less than the forward error correction (FEC) threshold of 3.8 × 10⁻³. This work pioneers the first validation of an LD source based on DBSM for UWOC, thereby increasing the number of available communication channels in the blue light spectrum.

由于蓝光在水下环境中具有优异的透射率，因此其范围已被确定为水下无线光通信（UWOC）的合适频谱。本文提出了一种基于405nm、450nm和488nm密集蓝谱复用（DBSM）的激光二极管（LD）源，在2.4 m水下链路中采用16正交调幅离散多音调制（16-QAM DMT），可实现18gbps的传输容量。每个三波长ld的数据速率最高可达6gbps，误码率分别为3.53 × 10-3、3.49 × 10-3和3.34 × 10-3，均小于FEC （forward error correction）阈值3.8 × 10-3。这项工作首次验证了基于DBSM的UWOC LD源，从而增加了蓝光频谱中可用通信信道的数量。

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引用次数: 0

Regulation of the Impact of Electron Beam on the Propagation of Dust-Ion Acoustic Waves 电子束对尘埃离子声波传播影响的调控

IF 1.7 4区物理与天体物理 Q2 PHYSICS, MULTIDISCIPLINARY

Brazilian Journal of Physics

Pub Date : 2025-12-19 DOI: 10.1007/s13538-025-01979-4

Amir Mohammad Ahadi

Comprehending the dynamics of dust acoustic modes and the ability to tune their effective parameters facilitates the optimization of plasma phenomena and structures, while also providing deeper insights into the underlying physics of oscillations involving massive charged grains. In this study, we investigate the influence of cathode potential on the evolution of dust ion acoustic (DIA) waves in a multicomponent dusty plasma containing a separate electron beam (e-beam). Our analysis reveals that cathode potential plays a crucial role in modulating the effect of the e-beam on DIA mode dynamics. Notably, at a specific cathode potential, denoted as (:{varphi:}_{CN}), the contribution of the e-beam to DIA wave propagation becomes negligible. Numerical results indicate that (:{varphi:}_{CN}) gradually increases with rising concentration of negatively charged grains, a trend that becomes more pronounced at elevated electron temperatures. Furthermore, in plasmas containing negatively charged grains, increasing the electron number density induces a nonlinear decrease in (:{varphi:}_{CN}), conversely, in plasmas with positively charged dust grains, the opposite trend is observed. Our findings offer an effective strategy for manipulating e-beam-induced modifications in DIA mode behavior.

了解尘埃声学模式的动力学和调整其有效参数的能力有助于等离子体现象和结构的优化，同时也为涉及大质量带电颗粒的振荡的潜在物理学提供了更深入的见解。在本研究中，我们研究了阴极电位对含有独立电子束（电子束）的多组分尘埃等离子体中尘埃离子声波（DIA）波演变的影响。我们的分析表明，阴极电位在电子束对DIA模式动力学的影响中起着至关重要的调节作用。值得注意的是，在特定的阴极电位下，表示为(:{varphi:}_{CN})，电子束对DIA波传播的贡献可以忽略不计。数值结果表明，(:{varphi:}_{CN})随带负电荷颗粒浓度的升高而逐渐增大，这一趋势在电子温度升高时更为明显。此外，在含有负电荷颗粒的等离子体中，电子数密度的增加导致(:{varphi:}_{CN})的非线性下降，相反，在带正电荷颗粒的等离子体中，观察到相反的趋势。我们的发现提供了一种有效的策略来操纵电子束引起的DIA模式行为的改变。

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引用次数: 0

Two decades of slot waveguides: light-matter interaction in integrated photonics 缝隙波导的二十年：集成光子学中的光-物质相互作用

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2025-12-19 DOI: 10.1016/j.optlastec.2025.114500

Muhammad Ali Butt

Slot waveguides have emerged as a key architecture in integrated photonics, enabling subwavelength confinement of light and greatly enhanced light-matter interaction. By exploiting the electric field discontinuity at high-index-low-index interfaces, slot geometries localize optical fields within nanoscale gaps, offering unique advantages over conventional strip and rib waveguides. Over the past two decades, slot waveguides have been demonstrated across diverse material platforms including silicon, polymers, chalcogenide glasses, lithium niobate, III-V semiconductors, and emerging two-dimensional materials. These platforms support a broad range of applications, from nonlinear photonics and electro-optic modulation to biochemical and gas sensing, with recent extensions into mid-infrared spectroscopy, terahertz guiding, quantum photonics, and neuromorphic computing. Despite their promise, slot waveguides face challenges related to fabrication tolerances, propagation losses, and material stability in hybrid designs. This review consolidates their fundamental principles, historical development, material platforms, and key applications, while critically assessing current limitations. Future perspectives highlight heterogeneous integration and application-driven design as pathways for establishing slot waveguides as foundational building blocks of next-generation integrated photonic platforms.

槽波导已成为集成光子学的关键结构，它实现了光的亚波长限制，并大大增强了光与物质的相互作用。通过利用高折射率-低折射率界面上的电场不连续，狭缝几何结构将光场定位在纳米级间隙内，与传统的条形波导和肋形波导相比，具有独特的优势。在过去的二十年里，槽波导已经在不同的材料平台上得到了证明，包括硅、聚合物、硫系玻璃、铌酸锂、III-V半导体和新兴的二维材料。这些平台支持广泛的应用，从非线性光子学和电光调制到生化和气体传感，最近扩展到中红外光谱学，太赫兹制导，量子光子学和神经形态计算。尽管槽波导前景光明，但在混合设计中仍面临制造公差、传播损耗和材料稳定性方面的挑战。本文综述了它们的基本原理、历史发展、材料平台和关键应用，同时批判性地评估了当前的局限性。未来的观点强调异构集成和应用驱动设计作为建立槽波导的途径，作为下一代集成光子平台的基础构建模块。

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引用次数: 0

Multi-frequency feature collaborative network for low-light image enhancement 弱光图像增强的多频特征协同网络

IF 5 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2025-12-19 DOI: 10.1016/j.optlastec.2025.114510

Yang Qin , Fengna Cheng , Shengqin Jiang

Low-light image degradation typically appears as the loss of high-frequency details (e.g., edge blurring) and distortions in low-frequency structures (e.g., color deviations). Thus, existing methods often adopt encoder–decoder frameworks to restore normal-light images, where shallow layers primarily capture high-frequency features and deeper layers focus on low-frequency components. However, this hierarchical separation results in a disjointed treatment of frequency components, limiting the model’s ability to capture their intrinsic relationships and ultimately hindering further performance gains. To this end, we propose a multi-frequency feature collaborative network for low-light image enhancement. We begin by introducing a multi-frequency collaborative learning strategy that leverages multiple distinct filters to extract prior information associated with specific frequency components to compensate for the loss of frequency information at each level of the network. Then we propose a collaborative fusion module to efficiently integrate these transformed priors with their corresponding hierarchical network features. This design captures interactive patterns among complementary frequency components across different network layers, thereby enhancing the modeling of complex mappings between low-light and normal-light images. Furthermore, we propose a channel-correlation correction loss, which anchors one color channel while constraining pixel differences across channels. This constraint captures subtle inter-pixel relationships within latent color channels, promoting more accurate color restoration. Finally, we validate the effectiveness of our method on multiple datasets, achieving state-of-the-art performance. Code is available at https://anonymous.4open.science/r/mfcn-81F6.

弱光图像退化通常表现为高频细节的丢失（例如，边缘模糊）和低频结构的扭曲（例如，颜色偏差）。因此，现有的方法通常采用编码器-解码器框架来恢复正光图像，其中浅层主要捕获高频特征，而深层则专注于低频成分。然而，这种分层分离导致频率分量的处理脱节，限制了模型捕捉其内在关系的能力，最终阻碍了进一步的性能提升。为此，我们提出了一种多频特征协同网络用于弱光图像增强。我们首先介绍了一种多频率协同学习策略，该策略利用多个不同的滤波器来提取与特定频率成分相关的先验信息，以补偿网络每个级别上频率信息的损失。然后，我们提出了一个协同融合模块，将这些转换后的先验与相应的层次网络特征有效地融合在一起。该设计捕获了跨不同网络层的互补频率分量之间的交互模式，从而增强了低光和正常光图像之间复杂映射的建模。此外，我们提出了一个通道相关校正损失，它锚定一个颜色通道，同时约束通道之间的像素差异。该约束捕获潜在颜色通道内微妙的像素间关系，促进更准确的颜色恢复。最后，我们在多个数据集上验证了我们方法的有效性，实现了最先进的性能。代码可从https://anonymous.4open.science/r/mfcn-81F6获得。

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引用次数: 0

Simulation of the Recording of the Brightest Gamma-ray Burst GRB 221009A by a Segmented Scintillation Detector 分段闪烁探测器记录最亮伽马暴GRB 221009A的模拟

IF 0.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Astronomy Letters-A Journal of Astronomy and Space Astrophysics

Pub Date : 2025-12-19 DOI: 10.1134/S1063773725700410

A. A. Mkrtchyan, A. S. Pozanenko, P. Yu. Minaev, D. D. Frederiks

We have simulated the recording of one of the brightest gamma-ray bursts, GRB 221009A, with a segmented scintillation detector. Based on the analysis of Konus-WIND observations, we reproduced the spectral characteristics of the burst in our simulation. Particular attention was given to the influence of instrumental (dead time and pile-up) effects on the accuracy of reconstructing the energy spectrum and polarization of the emission at extremely high fluxes. Detector segmentation was shown to reduce significantly the distortion of the recorded spectrum. We found that a reliable polarization measurement is possible at fluxes up to ({sim}10^{-5}) erg cm({}^{-2}) s({}^{-1}), whereas at fluxes ({sim}10^{-2}) erg cm({}^{-2}) s({}^{-1}) (the main peak of the burst light curve) a polarization measurement is impossible due to the significant influence of the dead time and pile-up effects.

我们用一个分段闪烁探测器模拟了最亮的伽马射线爆发之一GRB 221009A的记录。基于对Konus-WIND观测数据的分析，我们在模拟中再现了爆发的光谱特征。特别注意了仪器（死区和堆积）效应对重建极高通量发射能谱和极化精度的影响。结果表明，检测器分割可以显著降低记录光谱的失真。我们发现，在通量高达({sim}10^{-5}) erg cm ({}^{-2}) s ({}^{-1})处可以进行可靠的偏振测量，而在通量({sim}10^{-2}) erg cm ({}^{-2}) s ({}^{-1})（爆发光曲线的主峰）处，由于死区时间和堆积效应的显著影响，无法进行偏振测量。

引用次数: 0

Seeking the nearest neutron stars using a new local electron density map 用新的局部电子密度图寻找最近的中子星

IF 6.4 2区物理与天体物理 Q1 ASTRONOMY & ASTROPHYSICS

Journal of Cosmology and Astroparticle Physics

Pub Date : 2025-12-19 DOI: 10.1088/1475-7516/2025/12/051

Joseph Bramante, Katherine Mack, Nirmal Raj, Lijing Shao and Narayani Tyagi

Neutron stars provide a compelling testing ground for gravity, nuclear dynamics, and physics beyond the Standard Model, and so it will be useful to locate the neutron stars nearest to Earth. To that end, we revisit pulsar distance estimates extracted from the dispersion measure of pulsar radio waves scattering on electrons. In particular, we create a new electron density map for the local kiloparsec by fitting to parallax measurements of the nearest pulsars, which complements existing maps that are fit on the Galactic scale. This “near-Earth” electron density map implies that pulsars previously estimated to be around a hundred parsecs from Earth will require a long-baseline parallax measurement campaign, both to improve local electron density maps and determine the true distances to these promising pulsars. Nearby neutron stars would be valuable laboratories for testing fundamental physics phenomena, including several late-stage neutron star heating mechanisms, using current and forthcoming telescopes. We estimate the sensitivities of the upcoming Extremely Large Telescope and Thirty Meter Telescope to neutron stars heated by dark matter capture, and find that long observing times are required.

中子星为标准模型之外的重力、核动力学和物理学提供了一个令人信服的试验场，因此定位离地球最近的中子星将是有用的。为此，我们重新审视从脉冲星无线电波在电子上散射的色散测量中提取的脉冲星距离估计。特别是，我们通过拟合最近脉冲星的视差测量值，为当地千秒差距创建了一个新的电子密度图，这补充了现有的适合银河系尺度的地图。这张“近地”电子密度图意味着，先前估计离地球约100秒差距的脉冲星将需要一个长基线视差测量活动，既可以改善局部电子密度图，又可以确定这些有希望的脉冲星的真实距离。附近的中子星将成为宝贵的实验室，可以利用现有和即将到来的望远镜，测试基本物理现象，包括几个中子星后期的加热机制。我们估计了即将到来的超大望远镜和30米望远镜对被暗物质俘获加热的中子星的灵敏度，发现需要很长的观测时间。

{"title":"Seeking the nearest neutron stars using a new local electron density map","authors":"Joseph Bramante, Katherine Mack, Nirmal Raj, Lijing Shao and Narayani Tyagi","doi":"10.1088/1475-7516/2025/12/051","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/12/051","url":null,"abstract":"Neutron stars provide a compelling testing ground for gravity, nuclear dynamics, and physics beyond the Standard Model, and so it will be useful to locate the neutron stars nearest to Earth. To that end, we revisit pulsar distance estimates extracted from the dispersion measure of pulsar radio waves scattering on electrons. In particular, we create a new electron density map for the local kiloparsec by fitting to parallax measurements of the nearest pulsars, which complements existing maps that are fit on the Galactic scale. This “near-Earth” electron density map implies that pulsars previously estimated to be around a hundred parsecs from Earth will require a long-baseline parallax measurement campaign, both to improve local electron density maps and determine the true distances to these promising pulsars. Nearby neutron stars would be valuable laboratories for testing fundamental physics phenomena, including several late-stage neutron star heating mechanisms, using current and forthcoming telescopes. We estimate the sensitivities of the upcoming Extremely Large Telescope and Thirty Meter Telescope to neutron stars heated by dark matter capture, and find that long observing times are required.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"1 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145801443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dichroism and Birefringence in X-Ray Spectra of Forbidden Reflections 禁止反射x射线光谱的二色性和双折射

IF 0.4 4区物理与天体物理 Q4 PHYSICS, MULTIDISCIPLINARY

Moscow University Physics Bulletin

Pub Date : 2025-12-18 DOI: 10.3103/S0027134925701073

M. V. Gorbunova, E. N. Ovchinnikova, A. P. Oreshko

An approach employing the transmittance matrix has been implemented to calculate the intensity of Bragg reflections in resonant X-ray diffraction. This enables the inclusion of anisotropic effects that lead to a change in the polarization of radiation during propagation. Using the example of processing the spectra of forbidden reflections in an iron orthoborate crystal, performed with a program based on this approach, an improvement in the agreement between calculated results and experimental data is demonstrated in comparison with standard methods.

采用透射率矩阵计算了谐振x射线衍射中的布拉格反射强度。这使得包括各向异性效应，导致在传播期间辐射的偏振变化。以邻硼酸铁晶体禁反射光谱为例，用该方法编制的程序进行了处理，结果表明，与标准方法相比，计算结果与实验数据的一致性得到了提高。

引用次数: 0

Molybdenum Monocrystalline Material for Ultraviolet Plasmonics 紫外光等离子体用钼单晶材料

IF 11 1区物理与天体物理 Q1 OPTICS

Laser & Photonics Reviews

Pub Date : 2025-12-18 DOI: 10.1002/lpor.202501089

Zhe Liu, Yan Shen, Tao Cui, Xing Zhen, Tao Liu, Runze Zhan, Shuai Tang, Yu Zhang, Huanjun Chen, Lei Shao, Shaozhi Deng

Ultraviolet (UV) plasmonics has great potential in the applications of nano‐optoelectronic devices, food safety, and medical diagnosis. However, the reliable fabrication of high‐quality UV plasmonic materials remains a challenge. The commonly used UV plasmonic materials, such as Al and Pd, suffer from their poor morphological stability, surface roughness, and crystalline quality. In this study, we demonstrate a millimeter‐scale ultrasmooth molybdenum (Mo) monocrystal with a root‐mean‐square roughness of 0.282 nm, prepared via thermal evaporation deposition, exhibiting exceptional UV plasmonic performance. The growth mechanism of the Mo monocrystalline film is revealed using molecular dynamics methods. Additionally, highly repeatable plasmonic nanostructures are fabricated via focused ion beam milling and hole‐mask colloidal lithography. Such structures exhibit surface plasmon polariton (SPP) and localized surface plasmon resonance (LSPR) properties in the UV range. At the Mo‐air interface, the ratio of SPP propagation length to the decay length in dielectric materials reaches 12.74, and the field enhancement of LSPR has been shown to reach 102 times. The developed Mo monocrystalline material therefore exhibits promising plasmonic characteristics in the UV band, which together with its high melting point, strong structural stability, and excellent thermal conductivity, makes it promising for constructing UV plasmonic devices.

紫外等离子体在纳米光电器件、食品安全和医疗诊断等方面具有巨大的应用潜力。然而，高质量的紫外等离子体材料的可靠制造仍然是一个挑战。常用的UV等离子体材料，如Al和Pd，存在形态稳定性差、表面粗糙和结晶质量差的问题。在这项研究中，我们展示了一种毫米级的超光滑钼（Mo）单晶，其均方根粗糙度为0.282 nm，通过热蒸发沉积制备，具有优异的紫外等离子体性能。利用分子动力学方法揭示了Mo单晶膜的生长机理。此外，通过聚焦离子束铣削和孔掩膜胶体光刻技术制备了高度可重复的等离子体纳米结构。这种结构在紫外范围内表现出表面等离子激元（SPP）和局部表面等离子激元共振（LSPR）的特性。在Mo - air界面处，介质材料中的SPP传播长度与衰减长度之比达到12.74，LSPR的场增强达到102倍。因此，所开发的Mo单晶材料在紫外波段表现出良好的等离子体特性，加上其高熔点、强结构稳定性和优异的导热性，使其在构建紫外等离子体器件方面具有前景。

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引用次数: 0

Strain engineering of intrinsic multiferroic coupling in bilayer ScI2 双层ScI2中本征多铁耦合的应变工程

IF 4 2区物理与天体物理 Q2 PHYSICS, APPLIED

Applied Physics Letters

Pub Date : 2025-12-18 DOI: 10.1063/5.0281087

Xin Wang, Nan Wang, Yaru Chen, Tielei Song, Zhifeng Liu, Yan Xing, Xin Cui

Two-dimensional (2D) sliding ferroelectrics have emerged as promising candidates for next-generation nonvolatile memory technologies. However, integrating magnetic, ferroelectric, and ferrovalley properties within a single material system remains a significant challenge. Here, we propose a strategy combining interlayer sliding and strain engineering to synergistically control magnetism, ferroelectric polarization, magnetic anisotropy energy (MAE), and valley polarization in bilayer ScI2 through first-principles calculations. By altering the stacking order from AA to AB/BA configurations, the magnetic ground state transitions from antiferromagnetic (AFM) to ferromagnetic (FM) ordering, accompanied by the modulation of ferroelectric polarization and valley splitting. External strain further enables precise tuning of these properties: A compressive strain of −2% induces an AFM–FM transition in AB stacked ScI2, while a −6% strain enhances MAE beyond 1 meV. Notably, a tensile strain of 5.71% triggers a semiconductor-to-semimetal transition, transforming the ferrovalley state into a half-valley metal. These findings establish bilayer ScI2 as a versatile platform for the multifunctional device design, offering promising pathways to integrate charge, spin, and valley degrees of freedom in 2D multiferroics.

二维（2D）滑动铁电体已成为下一代非易失性存储技术的有希望的候选者。然而，在单一材料系统中集成磁性、铁电性和铁谷性仍然是一个重大挑战。本文提出了层间滑动与应变工程相结合的策略，通过第一性原理计算，协同控制双层ScI2的磁性、铁电极化、磁各向异性能（MAE）和谷极化。通过改变AA层序到AB/BA层序，磁性基态由反铁磁（AFM）向铁磁（FM）有序转变，并伴有铁电极化调制和谷分裂。外部应变进一步实现了这些特性的精确调谐：- 2%的压缩应变在AB堆叠的ScI2中诱导AFM-FM转变，而- 6%的应变使MAE超过1 meV。值得注意的是，5.71%的拉伸应变触发了半导体到半金属的转变，将铁谷态转变为半谷金属。这些发现确立了双层ScI2作为多功能器件设计的通用平台，为在二维多铁性材料中集成电荷、自旋和谷自由度提供了有希望的途径。

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引用次数: 0

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