Results in Optics最新文献_第6页

Fabrication of Whispering Gallery Mode (WGM) microresonator using core-to-core alignment fusion splicer for high sensitive temperature sensor trough optimum coupling gap with high q-factor 利用高q因子的最优耦合间隙，利用芯对芯对准熔接器制造高灵敏度温度传感器用窃窃廊模式（WGM）微谐振器

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-11-09 DOI: 10.1016/j.rio.2025.100928

Nur Aida Syahmina Noorbahrin , Nadrahtul Aqilah Mohd Yahaya , Siti Nurul Fatihah Azahan , Muhammad Khudhori Mohd Yusof , Sabrina Mohd Farid , Siti Nurfatinah Mohd Asseri , Retna Apsari , Mohd Zamani Zulkifli

In this work, the fabrication of whispering gallery mode (WGM) microsphere resonators using core-to-core alignment fusion splicer and its application as temperature sensors by optimization of coupling gap is studied and demonstrated. The proposed WGMs microsphere resonators are fabricated using core-to-core alignment fusion splicing technique, and the optimum coupling gap to a tapered fiber is made. Two configurations of coupling gap were tested, which are the 0 µm coupling gap in which both microsphere resonator and tapered fiber contacted, and 10 µm coupling gap. The sensor with 0 µm coupling gap recorded a finesse and Q-factor of 42.792 and 16,069.688 respectively at a resonance wavelength of 1542.69 nm. The sensor with 10 µm coupling gap recorded a finesse and Q-factor of 1.111 and 659.997 respectively at a resonance wavelength of 1544.40 nm. The temperature sensitivity was calculated to be 14.9 pm/°C, with a wavelength resolution of 6.7 × 10⁻² m°C and figure of merit (FOM) of 0.11/°C. The smaller gap resulted in a better sensitivity of the temperature sensor. The sensor has a substantial potential as a cost-effective, highly stable, and easy-to-fabricate. The proposed setup has been proven to be extremely sensitive to environmental changes, making them a highly potential alternative temperature sensor, further increasing their appeal for real world applications.

本文研究并演示了利用芯对芯对准熔接器制造窃窃廊模式（WGM）微球谐振器，并通过优化耦合间隙将其应用于温度传感器。采用芯对芯对准熔接技术制备了WGMs微球谐振器，获得了与锥形光纤的最佳耦合间隙。测试了微球谐振器与锥形光纤均接触的0µm耦合隙和10µm耦合隙两种耦合隙构型。耦合间隙为0µm的传感器在1542.69 nm的共振波长下，灵敏度和q因子分别为42.792和16069.688。耦合间隙为10µm的传感器在1544.40 nm的共振波长下，灵敏度和q因子分别为1.111和659.997。计算得到温度灵敏度为14.9 pm/°C，波长分辨率为6.7 × 10−2 m°C，性能图（FOM）为0.11/°C。间隙越小，温度传感器的灵敏度越高。该传感器具有巨大的潜力，具有成本效益，高度稳定，易于制造。所提出的设置已被证明对环境变化非常敏感，使其成为极具潜力的替代温度传感器，进一步增加了它们对现实世界应用的吸引力。

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引用次数: 0

UV-assisted synthesis of cadmium(II) diacetate dihydrate for the photocatalytic degradation of methylene blue: kinetics, pathway, and energy consumption 紫外光辅助合成二水合二乙酸镉光催化降解亚甲基蓝：动力学、途径和能量消耗

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-11-09 DOI: 10.1016/j.rio.2025.100927

Amir Azizi , Minoo Shariati , Parisa Ahmadi

This study focuses on the UV-assisted synthesis and investigation of Cadmium(II) Diacetate dihydrate [Cd(CH₃COO)₂·2H₂O] (CdDD) it assesses its effectiveness as a liquid photocatalyst for degrading the methylene blue dye (MB). The synthesized compound was characterized using Dynamic Light Scattering (DLS), Ultraviolet–visible (UV–Vis) spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), and Nuclear Magnetic Resonance (NMR) spectroscopy. Using DLS Analysis, the uniform particle size distribution of liquid CdDD was confirmed, and the mean particle size (z-average) was determined to be 101.66 nm with a Polydispersity Index (PdI) of 0.0014. Band gap energy (E_g) of liquid CdDD is estimated to be 3.3 eV. FT-IR and NMR analyses confirm the successful formation of the desired catalyst structure. Liquid CdDD as a photocatalyst for MB degradation was evaluated and optimized. Degradation efficiency of 93 % was achieved under optimum conditions of [MB]_o = 20 mg/L, [CdDD] = 10 ml/L, pH of 2, and [30 % H₂O₂] = 2.5 ml. The kinetic model under optimum conditions, pseudo-first-order, was obtained, with a rate constant of 0.06232 min⁻¹. Also, the half-life values for concentrations of 5, 10, 20, and 40 ppm of MB dye were evaluated and obtained as 26.45, 23.9 min, 20.7 min, and 78.8 min, respectively. Furthermore, the electrical energy consumption (E_EC) and the process evaluation criterion (PE) were recorded as 303.8 kWh/m³ and 2.15 × 10⁻², respectively, and the results were compared with related reported processes. The most significant outcome of this study is the introduction of CdDD as an effective liquid catalyst in the photodegradation of organic pollutants.

本文研究了紫外辅助合成二乙酸二水镉[Cd(CH3COO)2·2H2O] (CdDD)，并考察了其作为液体光催化剂降解亚甲基蓝染料（MB）的效果。采用动态光散射（DLS）、紫外-可见（UV-Vis）光谱、傅里叶变换红外光谱（FT-IR）和核磁共振（NMR）光谱对合成的化合物进行了表征。DLS分析证实液体CdDD粒径分布均匀，平均粒径（z-average）为101.66 nm，多分散性指数（PdI）为0.0014。液态CdDD的带隙能（Eg）估计为3.3 eV。FT-IR和NMR分析证实了催化剂结构的成功形成。对液态CdDD作为光催化剂降解MB进行了评价和优化。在[MB]o = 20 mg/L, [CdDD] = 10 ml/L, pH = 2, [30% H2O2] = 2.5 ml的最佳条件下，降解效率为93%，获得了最佳条件下的准一级动力学模型，速率常数为0.06232 min−1。此外，对浓度为5、10、20和40 ppm的MB染料进行了半衰期评估，分别为26.45、23.9 min、20.7 min和78.8 min。记录了该工艺的电耗（EEC）和工艺评价标准（PE）分别为303.8 kWh/m3和2.15 × 10−2，并与相关报道的工艺进行了比较。本研究最重要的成果是引入了CdDD作为光降解有机污染物的有效液体催化剂。

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引用次数: 0

Optimization techniques for power conversion efficiency boosting in lead-free Cs2SnI4Br2-based perovskite solar cell 提高无铅cs2sni4br2基钙钛矿太阳能电池功率转换效率的优化技术

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-11-09 DOI: 10.1016/j.rio.2025.100929

Tahani I. Al-Muhimeed , Mostafa Salah , Omar Abdelsamad , Ahmed Shaker , Mohamed Mousa

Lead-free perovskite solar cells (PSCs) are promising for sustainable photovoltaics; however, their performance remains below that of their lead-based counterparts. In this study, we investigate Cs₂SnI₄Br₂ PSCs using SCAPS-1D simulations calibrated to experimental baselines and systematically optimize key design parameters. Some design recommendations are provided for lead-free Cs₂SnI₄Br₂-based PSCs aimed at fostering sustainable and environmentally friendly photovoltaic (PV) solutions. By replacing TiO₂ with tungsten disulfide as the electron-transport layer (ETL), the conduction-band offset (CBO) is tuned to a favorable + 0.18 eV, enabling suppressed recombination. The effects of tuning the metal work function of both the front and back electrodes, as well as the doping levels of the transport layers, are also investigated. The thickness and bulk defects of the absorber layer are further studied. Also, the effect of interfacial defects is investigated. Collectively, these design choices raise the simulated PCE from 2.03 % to 9.47 %. Energy loss analysis indicates that absorption remains the dominant loss mechanism. Achieving a PCE exceeding 28 % requires modifications to the optical properties of the photoactive layer, addressing one of the most critical challenges in enhancing overall device performance. These promising findings unveil the potential application of inorganic lead-free Cs₂SnI₄Br₂-based PSCs for sustainable photovoltaic applications.

无铅钙钛矿太阳能电池（PSCs）是一种很有前途的可持续光伏发电材料；然而，它们的性能仍然低于铅基电池。在本研究中，我们使用SCAPS-1D模拟校准实验基线来研究Cs2SnI4Br2 PSCs，并系统优化关键设计参数。本文对基于cs2sni4br2的无铅PSCs提供了一些设计建议，旨在促进可持续和环保的光伏（PV）解决方案。通过用二硫化钨取代TiO2作为电子传输层（ETL），将导带偏移（CBO）调谐到有利的+ 0.18 eV，实现抑制复合。本文还研究了调整前后电极的金属功函数以及输运层掺杂水平的影响。进一步研究了吸收层的厚度和体积缺陷。同时，对界面缺陷的影响进行了研究。总的来说，这些设计选择将模拟PCE从2.03%提高到9.47%。能量损失分析表明，吸收仍然是主要的损失机制。实现超过28%的PCE需要修改光活性层的光学特性，解决提高整体设备性能的最关键挑战之一。这些有希望的发现揭示了无机无铅cs2sni4br2基PSCs在可持续光伏应用中的潜在应用。

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引用次数: 0

Integrated Artificial Magnetic Conductor Minkowski Island fractal terahertz antenna (AMC-MIFA) for future Communications 面向未来通信的集成人工磁导体Minkowski岛分形太赫兹天线（AMC-MIFA）

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-30 DOI: 10.1016/j.rio.2025.100921

Jeremiah O. Abolade , Dominic B.O. Konditi

A terahertz Minkowski Island fractal antenna (MIFA) is presented in this work. The MIFA is etched on a 0.38

λ_{o}

× 0.38

λ_{o}

substrate with a resonant frequency of 0.29THz. An Artificial Magnetic Conductor (AMC) based on the first iteration Minkowski Island fractal is designed and incorporated to improve antenna performance, such as gain and radiation efficiency at terahertz frequency for the first time in this work. The proposed antenna (MIFA with integrated AMC) footprint is 0.47

λ_{o}

× 0.47

λ_{o}

. The integration of AMC on the MIFA results in a 287.5 % increase in gain and 50 % increase in radiation efficiency. The bending analysis of the MIFA is investigated, and it was discovered that the proposed MIFA demonstrated a stable response. Therefore, the proposed MIFA is a suitable candidate for Terahertz applications such as body area network and medical diagnostics and telemedicine.

提出了一种太赫兹闵可夫斯基岛分形天线（MIFA）。MIFA蚀刻在0.38 λo × 0.38 λo基片上，谐振频率为0.29THz。本文首次设计了一种基于Minkowski岛分形的人工磁导体（AMC），以提高天线在太赫兹频率下的增益和辐射效率。该天线（集成AMC的MIFA）占地面积为0.47 λo × 0.47 λo。将AMC集成到MIFA上，增益提高287.5%，辐射效率提高50%。对MIFA进行了弯曲分析，发现该MIFA具有稳定的响应。因此，拟议的MIFA是太赫兹应用的合适候选者，例如体域网络和医疗诊断和远程医疗。

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引用次数: 0

A low jitter regenerative amplification picosecond pulse laser with the external trigger signal as local main wave for the SLR 一种以外部触发信号作为单反主波的低抖动再生放大皮秒脉冲激光器

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-30 DOI: 10.1016/j.rio.2025.100922

Mingliang Long , Zhibo Wu , Ming Wen , Yan Liang , Haifeng Zhang , Hao Chang , Huarong Deng , Zhongping Zhang

A distributed feedback picosecond (DFB) pulse laser has been designed with a single pulse energy of 5 pJ and a pulse width of 200 ps, resulting in a spectrum width of 0.12 nm. By controlling the time sequence of the DFB picosecond pulse laser and regenerative amplification (RA) at a repetition rate of 5 kHz and pulse width of 200 ps, the single-pulse energy has been amplified to 320 μJ, an amplification factor of 6.4 × 10⁷ is achieved. After frequency doubling, an average power of 0.6 W for the green picosecond laser is obtained, the synchronization accuracy of root mean square (RMS) between the pulse picosecond laser and the external signal is 18.1 ps. Based on the principle of satellite laser ranging (SLR), an external trigger signal has been used to replace the locally collected laser pulse as the local main wave. This new approach has been implemented in the SLR system at the Shanghai Astronomical Observatory, allowing for measurements of low-earth orbit, medium-earth orbit, high-altitude orbit, and geosynchronous (GEO) orbit (∼36000 km) satellites with a measurement accuracy ranging from 6 mm to 20 mm. It is the first successful integration of a DFB + RA-based low jitter picosecond laser with an externally triggered signal as the primary waveform for SLR of multiple satellites,it provides a new and innovative method for laser ranging.

设计了单脉冲能量为5 pJ、脉冲宽度为200 ps的分布式反馈皮秒（DFB）脉冲激光器，其谱宽为0.12 nm。通过控制DFB皮秒脉冲激光器的时间顺序，并以5 kHz的重复频率和200 ps的脉冲宽度进行再生放大（RA），可将单脉冲能量放大到320 μJ，放大倍数为6.4 × 107。经倍频后，获得的绿色皮秒激光平均功率为0.6 W，脉冲皮秒激光与外部信号的同步精度均方根（RMS）为18.1 ps。基于卫星激光测距（SLR）原理，利用外部触发信号代替局部采集的激光脉冲作为局部主波。这种新方法已经在上海天文台的SLR系统中实施，允许测量低地球轨道、中地球轨道、高海拔轨道和地球同步（GEO）轨道（~ 36000公里）卫星，测量精度范围从6毫米到20毫米。这是首次成功地将基于DFB + ra的低抖动皮秒激光器与外部触发信号作为多卫星单反的主波形集成在一起，为激光测距提供了一种新的创新方法。

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引用次数: 0

Sub-megahertz laser stabilization by harnessing orthogonality between the acousto-optic modulator dither and atomic spectroscopy 利用声光调制器抖动和原子光谱学之间的正交性实现亚兆赫激光稳定

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-27 DOI: 10.1016/j.rio.2025.100920

Phatwarach Siriworakoonchai , Parinya Udommai , Nuttanan Tanasanchai , Waranont Anukool

A sub-MHz frequency stability of the laser is crucial in the quantum-atom experiment where precise atomic transition is required for control and manipulation of atom like in the atom quantum computing. In this work, we have built the frequency stabilization system for the lasers used in our cold Rubidium atom experiment in the magneto-optical trap (MOT) and the optical tweezers. We utilized a Rubidium vapour glass cell as a frequency reference, which provides atomically absolute reference point with low complexity setup. By mean of the absorption of the laser beam by the Rubidium vapour, the saturated absorption spectroscopy (SAS) experiment was setup to produce the D2 line spectra. The acousto-optic modulator (AOM) was used to sinusoidally dither the laser frequency and consequently the resonance peaks in the spectra. Detailing in this work, the AOM sinusoidal dithering and the dithered SAS signal had orthogonality and were processed together to produce the error signal used to stabilize the laser frequency to the resonant peak. This frequency stabilization system achieved the frequency standard deviation below

0.80

MHz over up to 800 minutes period. The system also allowed for stabilized frequency tunability over a range of

55 - 60

MHz about the target resonance peak. This performance is significant for stabilizing the lasers in the MOT experiment and related quantum-atom research.

在量子原子实验中，如在原子量子计算中需要精确的原子跃迁来控制和操纵原子，激光的亚兆赫频率稳定性是至关重要的。在本工作中，我们在磁光阱和光镊中建立了冷铷原子实验用激光器的稳频系统。我们使用铷蒸汽玻璃电池作为频率参考，它提供了原子绝对参考点，设置复杂性低。利用铷蒸气对激光束的吸收，建立了饱和吸收光谱（SAS）实验，得到了D2谱线。利用声光调制器（AOM）对激光频率进行正弦抖动，从而得到光谱中的共振峰。在本工作中，AOM正弦抖动和抖动后的SAS信号具有正交性，并共同处理产生误差信号，用于将激光频率稳定在谐振峰值。该频率稳定系统在长达800分钟的时间内实现了低于0.80 MHz的频率标准偏差。该系统还允许在目标共振峰值的55-60 MHz范围内稳定频率可调性。这一性能对激光在MOT实验中的稳定以及相关的量子原子研究具有重要意义。

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引用次数: 0

Imaging through scattering media with a non-symmetric U-Net 非对称u网散射介质成像

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-27 DOI: 10.1016/j.rio.2025.100923

Xuyu Zhang , Libang Chen , Xuying Zhang , Dawei Zhang , Songlin Zhuang , Shensheng Han , Honglin Liu

Deep learning has been widely applied in imaging through scattering media, showing advantages in penetration depth, resolution, dynamic adaptivity, et al. Due to requirements of network architecture and/or computation efficiency, the recorded speckle pattern is usually cropped or downsampled to reduce the size of the input, which often leads to severely degraded reconstruction under incoherent illumination, when target information is encoded in low-contrast speckles. In this study, we propose a non-symmetric U-Net to enhance information extraction from incoherent speckle patterns while maintaining a low cost in computation resources. The non-symmetric U-Net uses a deeper encoder to match the full-size speckle pattern and extract more feature information but a lightweight decoder to achieve target reconstruction. It has been demonstrated that the deep-contraction-shallow-expansion network structure can selectively enhance information extraction from high-frequency modulations in incoherent speckles that is overwhelmed by noise and can be easily averaged-out by downsampling. The study provides a new architectural paradigm for imaging with deep learning, which has significant research and application values in imaging fields with low coherence illuminations, such as autonomous driving detection and remote sensing.

深度学习已广泛应用于散射介质成像，在穿透深度、分辨率、动态自适应等方面具有优势。由于网络结构和/或计算效率的要求，通常会对记录的散斑模式进行裁剪或下采样以减小输入的大小，当目标信息编码为低对比度散斑时，这往往会导致在非相干光照下重构的严重退化。在本研究中，我们提出了一种非对称的U-Net，以增强从非相干散斑模式中提取信息的能力，同时保持较低的计算资源成本。非对称U-Net使用更深的编码器来匹配全尺寸散斑模式并提取更多的特征信息，而使用轻量级的解码器来实现目标重构。研究表明，深度收缩-浅扩张网络结构可以选择性地增强非相干散斑中高频调制的信息提取，而非相干散斑被噪声淹没，并且很容易被下采样平均。该研究为深度学习成像提供了一种新的架构范式，在自动驾驶检测、遥感等低相干光照成像领域具有重要的研究和应用价值。

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引用次数: 0

Designing scalable single-mode to seven-mode plasmonic filters utilizing disk and ring-shaped resonators 利用圆盘和环形谐振器设计可扩展的单模到七模等离子体滤波器

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-14 DOI: 10.1016/j.rio.2025.100919

Saeed Javid, Farzad Tavakkol Hamedani, Pejman Rezaei, Shiva Khani

In this paper, seven surface plasmon-based filters using a single disk resonator (DR) and a DR coupled with one to six ring-shaped resonators (RSRs) are proposed. In these configurations, the resonators are bidirectionally connected to a pair of metal–insulator-metal (MIM) waveguides. The initial filter structure, consisting of only a single DR, functions as a single-mode band-pass filter. By coupling a disk resonator with a ring-shaped resonator (RSR), a dual-mode filter is created. Following this pattern, each additional RSR introduce another mode to the transmission spectrum. Essentially, the innovative method detailed in this work allows for the creation of plasmonic filters capable of operating with one through seven distinct modes. By utilizing a consistent topology, the results for various structural geometries with different numbers of RSRs are achieved, showcasing true scalability. Moreover, the quality factor (Q-factor) of the resulting modes is enhanced by increasing the quantity of RSRs. Consequently, these filters detailed in this study are suitable as foundational designs for optical sensors that require varying levels of sensitivity. The insulator material employed is air, while silver, whose properties are described by the Drude model, is used as the metal. Every result was generated through the finite-difference time-domain method, a technique known for its numerical stability and minimal dispersion error. Due to the remarkable features such as single and multi-mode filtering, tunable resonant frequency, and variable Q-factor, the filter topologies proposed here can find applications in more complex designs, including optical sensors, demultiplexers, splitters, couplers, and so on.

本文提出了7种基于表面等离子体的滤波器，分别采用单盘谐振器（DR）和单盘谐振器与1 ~ 6个环形谐振器（rrs）耦合。在这些配置中，谐振器双向连接到一对金属-绝缘体-金属（MIM）波导。初始滤波器结构仅由单个DR组成，作为单模带通滤波器。通过将圆盘谐振器与环形谐振器（RSR）耦合，创建了双模滤波器。按照这种模式，每增加一个RSR，就会向传输频谱引入另一种模式。从本质上讲，这项工作中详细介绍的创新方法允许创建能够在一个到七个不同模式下工作的等离子体滤波器。通过使用一致的拓扑结构，可以实现具有不同rrs数量的各种结构几何形状，从而展示真正的可扩展性。此外，通过增加rsr的数量，得到的模态的质量因子（q因子）得到提高。因此，本研究中详细介绍的这些滤波器适用于需要不同灵敏度水平的光学传感器的基础设计。所使用的绝缘体材料是空气，而其性质由德鲁德模型描述的银被用作金属。每个结果都是通过时域有限差分法生成的，这种技术以其数值稳定性和最小色散误差而闻名。由于单模和多模滤波、可调谐谐振频率和可变q因子等显著特性，本文提出的滤波器拓扑可以在更复杂的设计中找到应用，包括光学传感器、解复用器、分路器、耦合器等。

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引用次数: 0

A symmetric dual-ring cross stub based dual-band THz metamaterial absorber design for permittivity sensing applications 一种用于介电常数传感应用的对称双环交叉短段双带太赫兹超材料吸收体设计

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-14 DOI: 10.1016/j.rio.2025.100917

Ahmed Alqurashi , Sayeeda Khanam , Esam Y.O. Zafar , Ahmed J.A. Al-Gburi

This paper presents a novel dual-band terahertz (THz) metamaterial absorber based on a symmetric dual-ring cross-stub (SDR-CS) resonator, designed for high-sensitivity permittivity sensing. The absorber, composed of aluminum resonators and a polyamide substrate, features a compact unit cell of 80 × 80 μm with rotational symmetry. It exhibits two strong absorption peaks at 1.26 THz and 2.29 THz with near-unity absorption. Detailed electromagnetic simulations reveal the physical mechanisms underpinning the dual-band response and confirm polarization insensitivity and angular stability up to 60° incidence under TE and TM polarizations. Crucially, the device demonstrates excellent sensing performance for refractive indices in the range 1.0–3.162, achieving sensitivities of 0.148 THz/RIU (148 GHz/RIU) and 0.28 THz/RIU (280 GHz/RIU) at the lower and higher resonance frequencies, respectively. The quality factors (Q) are 32.3 and 39.3, resulting in figure-of-merits (FOM) of 39.3 and 32.3 RIU–1, outperforming many reported metamaterial sensors with larger sizes or more complex materials. These attributes underscore the absorber’s potential as a compact, efficient, and highly sensitive platform for THz permittivity sensing with applications in biomedical diagnostics, chemical identification, and environmental monitoring.

本文提出了一种基于对称双环交叉短段（SDR-CS）谐振器的新型双带太赫兹（THz）超材料吸收体，用于高灵敏度介电常数检测。该吸收器由铝谐振器和聚酰胺衬底组成，具有80 × 80 μm的紧凑单元，具有旋转对称性。在1.26 THz和2.29 THz处有两个强吸收峰，吸收接近均匀。详细的电磁模拟揭示了支撑双波段响应的物理机制，并证实了TE和TM极化下60°入射下的极化不敏感和角稳定性。关键是，该器件在1.0-3.162折射率范围内表现出优异的传感性能，在低共振频率和高共振频率下分别达到0.148 THz/RIU （148 GHz/RIU）和0.28 THz/RIU （280 GHz/RIU）。质量因子(Q)分别为32.3和39.3，其优点系数（FOM）分别为39.3和32.3 RIU-1，优于许多报道的具有更大尺寸或更复杂材料的超材料传感器。这些特性强调了吸收剂作为一种紧凑、高效、高灵敏度的太赫兹介电常数传感平台的潜力，可用于生物医学诊断、化学鉴定和环境监测。

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引用次数: 0

Wideband 1 × 2 tree-shaped fractal antenna array with gain enhancement and sidelobe level reduction for sub-6 GHz 5G applications 用于sub-6 GHz 5G应用的增益增强和旁瓣电平降低的宽带1 × 2树形分形天线阵列

IF 3 Q3 Physics and Astronomy

Results in Optics

Pub Date : 2025-10-14 DOI: 10.1016/j.rio.2025.100918

Rania Hamdy Elabd , Ahmed J.A. Al-Gburi , Amany A. Megahed

This research presents a wideband (WB) 1 × 2 tree-shaped fractal antenna (TFA) array designed for sub-6 GHz 5G applications, featuring sidelobe level (SLL) reduction and gain enhancement. The array consists of two linearly arranged TFAs combined with a Wilkinson power divider (WPD) using a single-feed configuration. The WPD is selected due to its wide bandwidth, strong suppression factor, compact size, simple structure, excellent port isolation, and low insertion loss. A single TFA element, fabricated on a Rogers RT5880 substrate with a relative permittivity of 2.2 and a thickness of 1.57 mm, has dimensions of 38.5 × 49.5 mm². It operates from 2.2 GHz to beyond 5 GHz, achieving a gain of 2.2–4.5 dBi. The proposed 1 × 2 array layout measures 76.5 × 81.36 mm² and employs defected ground structure (DGS) and stub-loading techniques to suppress SLL and enhance gain. The array achieves a reflection coefficient better than –25 dB and an SLL of –13.2 dB. At the resonance frequency of 3.5 GHz, the gain improves significantly, rising from 3.2 dBi (single element) to 7.5 dBi (array). Simulated and experimental results confirm excellent agreement, validating the effectiveness of the proposed design.

本研究提出了一种用于sub-6 GHz 5G应用的宽带（WB） 1 × 2树形分形天线（TFA）阵列，具有降低旁瓣电平（SLL）和增强增益的特点。该阵列由两个线性排列的tfa与使用单馈电配置的威尔金森功率分配器（WPD）相结合组成。选择WPD的原因是其带宽宽、抑制系数强、体积小、结构简单、端口隔离性能好、插入损耗低。在Rogers RT5880衬底上制作的单个TFA元件的相对介电常数为2.2，厚度为1.57 mm，尺寸为38.5 × 49.5 mm2。它的工作范围为2.2 GHz至5 GHz以上，增益为2.2 - 4.5 dBi。提出的1 × 2阵列布局尺寸为76.5 × 81.36 mm2，采用缺陷接地结构（DGS）和存根加载技术来抑制SLL和提高增益。该阵列的反射系数优于-25 dB， SLL为-13.2 dB。在3.5 GHz的谐振频率下，增益显著提高，从3.2 dBi（单元件）上升到7.5 dBi（阵列）。仿真结果与实验结果吻合良好，验证了设计的有效性。

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