Optics Communications最新文献_第2页

Synergistic multi-resonance mode design for highly efficient broadband solar absorption and photothermal conversion using a cross-ring metamaterial array 基于交叉环超材料阵列的高效宽带太阳能吸收和光热转换的协同多共振模式设计

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-10 DOI: 10.1016/j.optcom.2026.132905

Rajib Lochan Ghadei, Rishi Maiti

Solar energy, the most abundant renewable resource on Earth, offers a clean and sustainable solution to meet the rising global energy demand. However, existing metamaterial-based solar absorbers often suffer from limited broadband absorption, polarization sensitivity, and narrow angular response, which restrict their practical applicability. To overcome these challenges, we propose a novel Ti/SiO₂/Ti cross-ring metasurface absorber that synergistically exploits localized surface plasmon resonance, Fabry-Pérot cavity resonance, and magnetic resonance within a single subwavelength unit cell. This multi-resonant coupling enables broadband, polarization-insensitive, and wide-angle absorption performance. Using Lumerical FDTD simulations, the proposed absorber achieves an average absorption of 94.2 % across a wide spectral range of 280–5000 nm, with maximum average absorptions of 96.0 % and 95.8 % for transverse electric and transverse magnetic polarizations, respectively. Near-perfect absorption peaks of 99.9 % are observed at resonance wavelengths of 334 nm and 658 nm. Moreover, the absorption closely matches the AM1.5 solar spectrum, resulting in an excellent solar absorption efficiency of 97 % in the 280–5000 nm range. The structure retains high absorption from normal incidence up to 60° and exhibits a thermal emission efficiency of 96.96 % at 2000 K, along with a photothermal conversion efficiency exceeding 91.5 % over the temperature range of 300–1000 K at a solar concentration factor of 1000. These enhancements demonstrate that the proposed metastructure is a highly promising candidate for advanced solar-thermal applications, including solar water heating, photothermal therapy, and concentrated solar power systems.

太阳能是地球上最丰富的可再生资源，为满足日益增长的全球能源需求提供了清洁和可持续的解决方案。然而，现有的基于超材料的太阳能吸收体往往存在窄带吸收、极化灵敏度和窄角响应等问题，限制了其实际应用。为了克服这些挑战，我们提出了一种新型的Ti/SiO2/Ti交叉环超表面吸收剂，它协同利用局部表面等离子体共振、fabry - psamro腔共振和单个亚波长单位细胞内的磁共振。这种多共振耦合实现了宽带、偏振不敏感和广角吸收性能。通过流形时域有限差分模拟，该吸收器在280-5000 nm宽光谱范围内的平均吸收率为94.2%，其中横向电极化和横向磁极化的最大平均吸收率分别为96.0%和95.8%。在334 nm和658nm的共振波长处观察到99.9%的近乎完美的吸收峰。此外，吸收与AM1.5太阳光谱密切匹配，在280-5000 nm范围内具有97%的优异太阳吸收效率。该结构在60°内保持高吸收率，在2000 K时热辐射效率为96.96%，在300-1000 K温度范围内，当太阳集中系数为1000时，光热转换效率超过91.5%。这些增强表明，所提出的元结构是一个非常有前途的先进太阳能热应用的候选者，包括太阳能热水、光热疗法和聚光太阳能发电系统。

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引用次数: 0

Machine learning-based enhanced visibility framework and predictive fog- and precipitation-induced attenuation modeling of subtropical free-space optical communication links 基于机器学习的增强可见度框架和亚热带自由空间光通信链路雾降水衰减预测模型

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-09 DOI: 10.1016/j.optcom.2026.132897

Okikiade Adewale Layioye , Pius Adewale Owolawi , Chunling Tu , Etienne Van Wyk , Joseph Sunday Ojo

Free-Space Optical (FSO) communication offers a powerful solution for high-speed and long-distance data transmission, but the quality of the performance is critically dependent on atmospheric conditions. This paper presents a comprehensive, data-driven framework for characterizing and predicting atmospheric attenuation from fog and rain for FSO links. Our analysis reveals a distinct non-Gaussian distribution for attenuation, with a small number of severe fog events dominating link degradation. The mean total attenuation for all cities is significantly higher with maximum values reaching over 170 dB/km, whereas rain attenuation peaks below 4 dB/km. A link budget analysis with a 26.6 dB fade margin demonstrates that for this configuration, rain is a negligible factor, with fog being the sole contributor to link outage. To address the challenge of real-time link management, a Random Forest (RF) regressor technique was trained to predict total attenuation from visibility and rain data. A systematic dual-split modeling approach (chronological time-forward splits and random shuffled splits) was employed to provide a comprehensive performance evaluation and to assess the RF model's performance both under general, independent and identically distributed assumptions and under realistic time-series forecasting conditions. The shuffled-split models, trained on a random mix of data, achieved a near-perfect coefficient of determination (

R^{2}

>0.9997) and very low root mean square error (RMSE ≈ 0.0300 dB/km) for most cities, confirming the model's fundamental ability to learn the underlying relationships. Feature importance analysis revealed visibility as the overwhelmingly dominant predictor, accounting for over 99 % of the model's predictive power. This work demonstrates that the proposed framework, augmented by machine learning, is a versatile and reliable tool for preliminary site assessment, link-outage probability calculation, and real-time link margin management in FSO networks. The findings provide a critical foundation for the deployment of FSO infrastructure in the climatically diverse South African landscape.

自由空间光学（FSO）通信为高速和远距离数据传输提供了强大的解决方案，但性能的质量严重依赖于大气条件。本文提出了一个全面的、数据驱动的框架，用于表征和预测FSO链路中雾和雨的大气衰减。我们的分析揭示了衰减的明显非高斯分布，少数严重雾事件主导了链路退化。所有城市的平均总衰减都显著较高，最大值可达170 dB/km以上，而降雨衰减峰值在4 dB/km以下。具有26.6 dB衰减裕度的链路预算分析表明，对于这种配置，雨是一个可以忽略不计的因素，雾是导致链路中断的唯一因素。为了解决实时链路管理的挑战，训练随机森林（RF）回归器技术来预测能见度和降雨数据的总衰减。采用系统的双分裂建模方法（按时间顺序向前分裂和随机打乱分裂）进行综合性能评估，并评估了RF模型在一般、独立和同分布假设以及实际时间序列预测条件下的性能。在随机混合数据上训练的打乱分割模型，对大多数城市实现了接近完美的决定系数（R2 >0.9997）和非常低的均方根误差（RMSE≈0.0300 dB/km），证实了该模型学习潜在关系的基本能力。特征重要性分析显示，可见性是压倒性的主要预测因素，占模型预测能力的99%以上。这项工作表明，所提出的框架，通过机器学习的增强，是FSO网络中初步站点评估、链路中断概率计算和实时链路余量管理的通用可靠工具。这一发现为在气候多样化的南非地区部署FSO基础设施提供了重要的基础。

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引用次数: 0

Four-state electro-optic switch operating in the short-wave infrared enabled by a dual transparent window C-bar-shaped antenna/AZO metasurface 双透明窗口c形天线/AZO超表面使能工作在短波红外的四态电光开关

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-09 DOI: 10.1016/j.optcom.2026.132899

Qiupeng Huang , Yanhua Xu , Zeliang Bai , Zhenbo Hu , Decheng Ni , Xiangqian Li , Guangming Li , Lili Miao

The short-wave infrared (SWIR) band has become a pivotal spectral window for optical communications, multi-wavelength routing, and integrated photonic logic circuits. Conventional electro-optic switches, however, still face significant challenges in channel count, modulation depth, and insertion loss. To achieve multi-state, broadband, low-loss asynchronous control, we propose a C-shaped split-ring antenna that generates a plasmon-induced-transparency (PIT)-like transparent window through plasmonic coupling between the antenna and the aluminum-doped zinc oxide (AZO) film, and integrate it into a dual-window C-bar-shaped antenna/AZO metasurface. The first window extends approximately 175 nm across the Near-Infrared I and II regions, while the second provides PIT-like transparency over 535 nm, covering the O- and C-telecommunication bands. Consequently, we demonstrate a four-state electro-optic switch realized on this C-bar-shaped antenna/AZO metasurface, in which the modulation of the AZO electron density enables operation from 920 to 1235 nm with a peak modulation depth of 97.08 %, an extinction ratio up to 15.35 dB, and an insertion loss as low as 0.83 dB. These findings offer quantitative design guidelines for next-generation photonic devices.

短波红外（SWIR）波段已成为光通信、多波长路由和集成光子逻辑电路的关键光谱窗口。然而，传统的电光开关在信道数、调制深度和插入损耗方面仍然面临重大挑战。为了实现多态、宽带、低损耗的异步控制，我们提出了一种c形裂环天线，该天线通过天线与掺铝氧化锌（AZO）薄膜之间的等离子体耦合产生类似于等离子体诱导透明（PIT）的透明窗口，并将其集成到双窗口c条形天线/AZO超表面中。第一个窗口在近红外I和II区域延伸约175 nm，而第二个窗口在535 nm范围内提供类似pit的透明度，覆盖O-和c -电信波段。因此，我们展示了在c -bar形天线/AZO超表面上实现的四态电光开关，其中AZO电子密度的调制可以在920到1235 nm范围内工作，峰值调制深度为97.08%，消光比高达15.35 dB，插入损耗低至0.83 dB。这些发现为下一代光子器件的定量设计提供了指导。

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引用次数: 0

Tunable dual-band infrared optical switch via surface plasmon resonance based on Ag nanodisks 基于银纳米片表面等离子体共振的可调谐双频红外光开关

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-09 DOI: 10.1016/j.optcom.2026.132898

Yiwen Yang, Qi Wang, Chen Wang, Mochi Guo, Tianrong Ouyang, Ruijin Hong, Dawei Zhang

A dual-band tunable infrared optical switch based on a plasmonic structure composed of metal nanodisks and vanadium dioxide film is proposed. Dynamic optical switch modulation of both operating wavelength and spectral reflectance intensity is achieved by leveraging the insulator-metal transition of vanadium dioxide. Finite-difference time-domain simulations demonstrate that the device operates at two operating wavelengths of 2389 nm and 2974 nm, achieving modulation depths of 65.8 % and 73.5 %, with extinction ratios up to 14.42 dB. Furthermore, by adjusting the nano-disk radii and their relative positions, the operating wavelength can be tuned over a range exceeding 1100 nm while maintaining polarization-independent and angle-insensitive characteristics. Benefiting from the ultrafast phase transition of VO₂, the proposed design provides low-power and high-speed switching, offering great potential for applications in dynamic and multifunctional devices such as optical modulations, tunable multiband filters, infrared photnics.

提出了一种基于金属纳米片和二氧化钒薄膜组成的等离子体结构的双频可调谐红外光开关。通过利用二氧化钒的绝缘体-金属过渡，实现了工作波长和光谱反射强度的动态光开关调制。时域有限差分仿真结果表明，该器件工作波长分别为2389 nm和2974 nm，调制深度分别为65.8%和73.5%，消光比高达14.42 dB。此外，通过调整纳米片半径及其相对位置，可以在超过1100 nm的范围内调谐工作波长，同时保持与偏振无关和角度不敏感的特性。得益于VO2的超快相变，该设计提供了低功耗和高速开关，为光学调制，可调谐多带滤波器，红外光电子等动态和多功能器件的应用提供了巨大的潜力。

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引用次数: 0

Improved joint subcarrier and power allocation with imperfect SIC in OFDM-NOMA VLC systems OFDM-NOMA VLC系统中SIC不完善的联合副载波和功率分配改进

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-09 DOI: 10.1016/j.optcom.2026.132896

Jiawei Chen, Jian Zhao

Orthogonal frequency division multiplexing non-orthogonal multiple access (OFDM-NOMA) visible light communication (VLC) systems suffer degraded performance from imperfect successive interference cancellation (SIC). In this paper, we propose a joint subcarrier-and-power allocation algorithm that considers diverse residual interference across subcarriers due to imperfect SIC. Simulation results show that the proposed algorithm offers a superior throughput-fairness balance compared to existing algorithms. In addition, the algorithm using diverse residual interference coefficients across subcarriers achieves higher throughput and better user fairness than that using a fixed coefficient.

正交频分复用非正交多址（OFDM-NOMA）可见光通信（VLC）系统由于不完全连续干扰消除（SIC）而导致性能下降。在本文中，我们提出了一种联合子载波和功率分配算法，该算法考虑了由于不完全SIC而导致的子载波之间的各种剩余干扰。仿真结果表明，与现有算法相比，该算法具有更好的吞吐量-公平性平衡。此外，使用不同子载波剩余干扰系数的算法比使用固定系数的算法具有更高的吞吐量和更好的用户公平性。

引用次数: 0

Edge-lit directional backlight based on tailored freeform optics 基于定制自由形状光学的边缘照明定向背光

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-09 DOI: 10.1016/j.optcom.2026.132902

Zijun Zhang, Haotian Sun, Yuqin Chen, Rengmao Wu

High-precision light manipulation is essential for advancing next-generation high-performance three-dimensional (3D) displays. The use of directional backlights in 3D display systems is thus motivated. However, state-of-the-art directional backlights are trapped in the tradeoff between uniformity, directionality, and form factors. Here, we introduce a novel edge-lit directional backlight based on tailored freeform optics. The 17.5 mm thick prototype produces an illumination area of 72 mm × 72 mm, with the uniformity of 94.1 %. The full width at half maximum (FWHM) of intensity distribution is 4.61° in the horizontal direction and 2.69° in the vertical direction. The proposed backlight provides exceptional uniformity, high directionality, and compact form factors simultaneously.

高精度的光操作对于推进下一代高性能三维（3D）显示器至关重要。因此，在3D显示系统中使用定向背光是有动机的。然而，最先进的定向背光被困在均匀性、方向性和外形因素之间的权衡中。在这里，我们介绍了一种基于定制自由曲面光学的新型边缘照明定向背光。17.5 mm厚的原型产生的照明面积为72mm × 72mm，均匀性为94.1%。强度分布的半最大值全宽度在水平方向为4.61°，在垂直方向为2.69°。所提出的背光同时提供卓越的均匀性、高方向性和紧凑的外形因素。

引用次数: 0

Thermally induced depolarization in multipass faraday isolators 多通法拉第隔离器的热致去极化

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-08 DOI: 10.1016/j.optcom.2026.132894

Aleksey Starobor, Oleg Palashov

Thermally induced depolarization in multipass Faraday isolators was studied. It was found that, from the point of view of thermal effects, 4 to 6 passes through a magneto-optical element, depending on magnetic field configuration, are optimal. Two axisymmetric cases of beam arrangement – in a ring and in a line – were considered. It was shown that in either case increasing the distance between the beams up to 1–1.5 diameters changes the magnitude of thermally induced depolarization to the level of individual elements. It was experimentally demonstrated that the thermally induced depolarization reduced by ∼2 times when the passes occur in a line.

研究了多通法拉第隔离器中的热致去极化现象。研究发现，从热效应的角度来看，通过磁光元件的4 ~ 6次通道随磁场构型的不同是最优的。考虑了两种轴对称情况下的梁布置——环形和直线。结果表明，在任何一种情况下，将光束之间的距离增加到1-1.5直径，都会将热致退极化的大小改变到单个元件的水平。实验证明，当通过在一条线上发生时，热诱导退极化减少了约2倍。

引用次数: 0

Quasi-bound state in continuum assisted lasing in one-dimensional blazed grating 一维燃烧光栅连续介质辅助激光的准束缚态

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-08 DOI: 10.1016/j.optcom.2026.132877

Diksha Sharma , Jyoti Mandal , Anjani Kumar Tiwari

Quasi-bound states in the continuum (QBIC) modes exhibit ultra-high quality factors with minimal radiative losses, enabling enhanced light–matter interactions and sharper spectral features. Realizing QBIC modes in practical devices typically requires carefully engineered structural asymmetry and precise geometric tuning, which pose significant fabrication challenges. In contrast, the blazed grating inherently introduces the required asymmetry and is easier to fabricate, making it a promising platform for realizing QBIC modes. In this paper, we numerically investigate the QBIC modes of a one-dimensional blazed grating structure on a silica platform. The optimized blazed grating supports both accidental and symmetry-protected QBIC modes for transverse electric and transverse magnetic polarization in the visible spectrum. The accidental QBIC modes are identified by their symmetric field profile, and the multipolar analysis confirms the dominant contribution from the toroidal dipole moment in the blazed grating structure. The symmetry-protected QBIC modes are identified through the antisymmetric field profile. At normal incidence under transverse electric polarization, the quality factors of the accidental and symmetry-protected QBIC modes are

1.6 \times 1 0^{4}

and

2.9 \times 1 0^{4}

, respectively. For transverse magnetic polarization, the quality factors of accidental and symmetry-protected QBIC modes are

5.9 \times 1 0^{4}

and

7.2 \times 1 0^{4}

. QBIC-assisted lasing is realized by incorporating optical gain in the ambient medium. Furthermore, by varying the angle of incidence, we show that the spectral position of the QBIC lasing mode can be tuned, enabling the realization of a QBIC-based tunable laser operating in the visible spectrum.

连续介质（QBIC）模式中的准束缚态以最小的辐射损失表现出超高质量因子，从而增强了光-物质相互作用和更清晰的光谱特征。在实际器件中实现QBIC模式通常需要精心设计结构不对称和精确的几何调谐，这对制造提出了重大挑战。相比之下，燃烧光栅固有地引入了所需的不对称性，并且更容易制造，使其成为实现QBIC模式的有前途的平台。本文对硅基平台上一维燃烧光栅结构的QBIC模式进行了数值研究。优化后的燃烧光栅在可见光谱中支持横向电极化和横向磁极化的意外和对称保护QBIC模式。通过场的对称分布来识别偶然QBIC模式，多极分析证实了燃烧光栅结构中环向偶极矩的主要贡献。通过反对称场轮廓来识别对称保护的QBIC模式。在横向电极化正入射下，意外和对称保护QBIC模式的质量因子分别为1.6×104和2.9×104。对于横向磁极化，意外和对称保护QBIC模式的质量因子分别为5.9×104和7.2×104。qbic辅助激光是通过在环境介质中加入光增益来实现的。此外，通过改变入射角，我们证明了QBIC激光模式的光谱位置可以调谐，从而实现了基于QBIC的可调谐激光器在可见光谱中工作。

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引用次数: 0

Optimized iterative algorithm for generating phase-only Fourier hologram based on phase momentum 基于相位动量生成纯相位傅立叶全息图的优化迭代算法

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-07 DOI: 10.1016/j.optcom.2025.132860

Ke Li, Jinbin Gui, Mengxue Li, Haoyu Liu, Wengping Zhong

The Gerchberg-Saxton (GS) iterative algorithm is a classical method for phase retrieval but suffers from slow convergence and dependence on the initial phase. This paper proposes an optimized iterative algorithm based on image-plane phase momentum acceleration and amplitude feedback. Unlike weighted-type algorithms that primarily impose constraints on amplitude, the proposed algorithm constructs a momentum term utilizing historical phase information in the image plane. This term adjusts the input image-plane phase in each iteration. When the actual change trend of the image-plane phase aligns with the momentum direction, a significant acceleration effect is produced, effectively reducing the number of iterations and shrinking the size of the noise region. Numerical simulations demonstrate that the proposed method achieves superior reconstruction quality with smaller noise regions and exhibits stronger robustness to initial phase conditions. Optical experimental results are consistent with simulations, further validating the effectiveness of the proposed method.

Gerchberg-Saxton （GS）迭代算法是一种经典的相位恢复方法，但其收敛速度慢且依赖于初始相位。提出了一种基于像面相位动量加速度和幅值反馈的优化迭代算法。与主要对振幅施加约束的加权型算法不同，该算法利用图像平面中的历史相位信息构建动量项。该项在每次迭代中调整输入图像平面相位。当像面相位的实际变化趋势与动量方向一致时，产生明显的加速效应，有效地减少了迭代次数，缩小了噪声区域的大小。数值仿真结果表明，该方法具有较好的重构质量和较小的噪声区域，对初始相位条件具有较强的鲁棒性。光学实验结果与仿真结果一致，进一步验证了该方法的有效性。

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引用次数: 0

Coupling performance of a planar lens to ultra slow-light photonic crystal waveguides: Simulation-based analysis and field distribution study 平面透镜与超慢光光子晶体波导的耦合性能：模拟分析与场分布研究

IF 2.5 3区物理与天体物理 Q2 OPTICS

Optics Communications

Pub Date : 2026-01-06 DOI: 10.1016/j.optcom.2026.132874

M. Amraie , T. Fathollahi-Khalkhali , A. Aghamohammadi , E. Lotfi

This study numerically investigates methods to improve the coupling efficiency between planar photonic crystal (PC) lenses and ultra-slow light PC waveguides. The structures consist of aluminum oxide rod arrays in air, where modified and geometrically optimized W1 and W2 waveguides are combined with a linearly graded square lattice PC lens to achieve efficient coupling. A single frequency source excites various configurations of slow light waveguides, enabling a controlled evaluation of their coupling behavior. The results show that the optimized designs preserve high coupling efficiency

11.75 d B

, with the best configuration exhibiting a marked enhancement when even compared to standard photonic crystal waveguides. These findings demonstrate that properly engineered planar PC lenses can reliably inject light into ultra-slow light PC waveguides with minimal loss, supporting the development of compact photonic integrated circuits that require enhanced light–matter interactions and precise control of signal delay.

本文对提高平面光子晶体透镜与超慢光光子晶体波导耦合效率的方法进行了数值研究。该结构由空气中的氧化铝棒阵列组成，其中改进和几何优化的W1和W2波导与线性渐变的方晶格PC透镜相结合，以实现高效耦合。单一频率源激发各种慢光波导的配置，使其耦合行为的可控评估。结果表明，优化后的结构保持了较高的耦合效率（11.75dB），与标准光子晶体波导相比，优化后的结构有明显的增强。这些发现表明，适当设计的平面PC透镜可以以最小的损耗可靠地将光注入超慢光PC波导，支持需要增强光与物质相互作用和精确控制信号延迟的紧凑型光子集成电路的发展。

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引用次数: 0