Results in Physics最新文献_第6页

Dual-band circularly polarized dielectric resonator antenna with wide impedance bandwidth and machine learning-assisted performance prediction 具有宽阻抗带宽和机器学习辅助性能预测的双频圆极化介质谐振器天线

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108531

Utkarsh Srivastava, Shreevatsa Gupta, Prerna Kumari, Upender Patri

This paper presents a compact dual-band dielectric resonator antenna (DRA) with circular polarization reconfigurability, optimized for UAV platforms, satellite communications, and emerging 6G networks. An elliptical ground slot enhances impedance bandwidth, while an asymmetric feeding structure excites orthogonal modes for robust circular polarization. The design achieves 111.1 % impedance bandwidth, dual axial ratio bandwidths of 60.4 % and 17.4 %, a peak gain of 12.8 dBic, and 95.07 % radiation efficiency. Alongside full-wave simulations, machine learning (ML) models—Artificial Neural Networks (ANN), XGBoost, and Random Forest—are employed to predict S11 and AR across 3–15 GHz. The models attain high accuracy (R2 > 0.93 for S11, R2 > 0.96 for AR) with low error values, validating their ability to capture complex electromagnetic behavior. This hybrid design and ML-assisted approach accelerate optimization, reduce simulation time, and provide reliable predictive capability. The proposed DRA’s combination of wideband performance, polarization agility, and ML integration makes it a strong candidate for compact, high-performance communication systems in UAVs, satellites, and next-generation wireless infrastructure.

本文提出了一种具有圆极化可重构性的紧凑型双频介质谐振器天线（DRA），针对无人机平台、卫星通信和新兴的6G网络进行了优化。椭圆地槽提高了阻抗带宽，而非对称馈电结构激发了正交模式，实现了鲁棒的圆极化。该设计实现了111%的阻抗带宽、60.4%和17.4%的双轴比带宽、12.8 dBic的峰值增益和95.07%的辐射效率。除了全波模拟，机器学习（ML）模型——人工神经网络（ANN）、XGBoost和随机森林——被用来预测3-15 GHz的S11和AR。模型获得了高精度（S11的R2 >； 0.93， AR的R2 >； 0.96）和低误差值，验证了它们捕获复杂电磁行为的能力。这种混合设计和ml辅助方法加速了优化，减少了仿真时间，并提供了可靠的预测能力。提议的DRA结合了宽带性能、极化敏捷性和ML集成，使其成为无人机、卫星和下一代无线基础设施中紧凑、高性能通信系统的有力候选者。

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引用次数: 0

Third-order response and improving the photovoltaic efficiency of the copolymer P3HT:PCBM doped with iodine as a solar cell 掺碘共聚物P3HT:PCBM作为太阳能电池的三阶响应和提高光伏效率

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108537

Abbas A. Sweaf , Harith A. Hasan , Hassan K. Ibrahim , Hussain A. Badran , Riyadh Ch. Abul-Hail , Khalid I. Ajeel

Z-scan method using a 532 nm laser wavelength was employed to determine the nonlinear refractive index (NORX) of an iodine polymer film. This technique involved a closed aperture that allowed part of the laser beam to pass through and reach the sensitive membrane of the detector. According to the measurements, NORX indicates that the iodine-doped PMMA film exhibits a negative nonlinearity, with

n_{2} = - 339.14 \times 10^{- 6} c m^{2} / W

. Furthermore, the value of the enhancement factor greater than one (

W_{merit}

>1) and a thermo-optic coefficient of 10⁻⁵, making it a promising material for numerous industrial applications. The effects of the iodine dye on preserving the full brightness of the polymer film over an extended period were also investigated. Beside that a mathematical model was studied using experimental values and found that the color matching functions of the iodine-doped PVP/PMMA films remained stable. A layer of pure P3HT:PCBM was prepared and then doped with different iodine concentrations (0.9 and 1.5 mM). Adding iodine to the P3HT:PCBM layer at a concentration of 1.5 mM increased the dark current by 3 times. The conductance-frequency (G-F) and capacitance-frequency (C-F) measurements were performed in the range of 0 Hz–100 MHz, and then the interface state number due to depletion was determined. The power conversion efficiency (PCE) to be in the range (1.066–1.383).This study demonstrated that the iodine-doped polymer film is a promising material for optoelectronics application such as polymer-dispersed liquid crystals, electrophoretic displays, and X-ray sensors.

采用532 nm激光波长的z扫描法测定了碘聚合物薄膜的非线性折射率（NORX）。这种技术涉及一个封闭的孔径，允许部分激光束通过并到达探测器的敏感膜。根据测量结果，NORX表明碘掺杂PMMA薄膜呈现负非线性，n2=-339.14×10-6cm2/W。此外，增强系数大于1 (Wmerit>1)，热光学系数为10−5，使其成为许多工业应用的有前途的材料。还研究了碘染料对长时间保持聚合物薄膜全亮度的影响。此外，利用实验值对数学模型进行了研究，发现碘掺杂PVP/PMMA薄膜的颜色匹配函数保持稳定。制备了一层纯P3HT:PCBM，然后分别掺杂不同浓度的碘（0.9和1.5 mM）。在P3HT:PCBM层中加入浓度为1.5 mM的碘，使暗电流增加3倍。在0 Hz-100 MHz范围内进行了电导-频率（G-F）和电容-频率（C-F）测量，然后确定了由于耗尽而导致的界面状态数。功率转换效率（PCE）在（1.066-1.383）范围内。该研究表明，碘掺杂聚合物薄膜在聚合物分散液晶、电泳显示、x射线传感器等光电子领域具有广阔的应用前景。

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引用次数: 0

Water desalination and highly efficient solar evaporation using the ferrite SnFe2O4/PVA: GA: AC hydrogel nanocomposite: Physical and photo-chemical properties 铁氧体SnFe2O4/PVA: GA: AC水凝胶纳米复合材料的海水淡化和高效太阳能蒸发：物理和光化学性质

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108539

M. Fargharazi, G. Sedaghati Jamal Abad, M.M. Bagheri Mohagheghi

This study designs a novel tin ferrite (SnFe₂O₄)/PVA: GA: activated carbon (AC) hydrogel evaporator material for solar water desalination. This approach addresses challenges in traditional seawater desalination, such as increasing the evaporation efficiency, the detrimental influence of condensed water droplets and water vapor on light absorption, and the difficulties in efficiently obtaining clean water. The PVA: GA: SnFe₂O₄/AC nanocomposite hydrogel was synthesized by dispersing SnFe₂O₄ nanoparticles and activated carbon (AC) in polyvinyl alcohol (PVA) and cross-linking it with glutaraldehyde (GA). The structural, optical, and morphological properties of the synthesized nanocomposite hydrogel were characterized using X-ray diffraction (XRD), UV–Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM). Fresh water preparation and solar evaporation experiments were performed in the presence a simulated the sunlight by an IR lamp (250 W, 2300 K), with intensity 2094 LUX. The synergistic photothermal and microporous properties of the nanocomposite hydrogel enabled an impressive evaporation rate of 3.85 kgm⁻²h⁻¹. Total dissolved solids (TDS) and inductively coupled plasma (ICP) analyses confirmed excellent salt resistance. Furthermore, distillation of Caspian seawaters significantly reduced the concentration of K⁺, Mg²⁺ Na⁺, and Hg²⁺ ions. Water hardness decreased from 6648 ppm to 213 ppm, and conductivity was reduced from 8651 µS/cm to 453 µS/cm, both complying with World Health Organization (WHO) standards. This work offers a promising avenue for further research to enhance the availability of drinking water in urban and rural communities through solar evaporation technology.

本研究设计了一种新型的锡铁氧体(SnFe2O4)/PVA: GA：活性炭（AC）水凝胶蒸发器材料用于太阳能海水淡化。该方法解决了传统海水淡化面临的难题，如提高蒸发效率、冷凝水滴和水蒸气对光吸收的不利影响以及高效获取清洁水的困难。将SnFe2O4纳米粒子与活性炭分散在聚乙烯醇（PVA）中，并与戊二醛（GA）交联，制备了PVA: GA: SnFe2O4/AC纳米复合水凝胶。利用x射线衍射（XRD）、紫外-可见光谱（UV-Vis）、傅里叶变换红外光谱（FTIR）和场发射扫描电镜（FESEM）对合成的纳米复合水凝胶的结构、光学和形态特性进行了表征。在250 W， 2300 K， 2094 LUX的模拟红外光照射下，进行了淡水制备和太阳能蒸发实验。纳米复合水凝胶的协同光热和微孔特性使其蒸发速率达到了令人印象深刻的3.85 kgm−2h−1。总溶解固体（TDS）和电感耦合等离子体（ICP）分析证实了其优异的耐盐性。此外，里海海水的蒸馏法显著降低了K+、Mg2+ Na+和Hg2+离子的浓度。水的硬度从6648 ppm降至213 ppm，电导率从8651µS/cm降至453µS/cm，均符合世界卫生组织（WHO）的标准。这项工作为进一步研究通过太阳能蒸发技术提高城市和农村社区饮用水的可获得性提供了一条有希望的途径。

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引用次数: 0

Bayesian regularization neural network analysis of heat and mass transfer in hybrid nanofluid flow over a lubricated stretching sheet with power-law lubricant layer and magnetic field effects 具有幂律润滑层和磁场效应的混合纳米流体流动传热传质的贝叶斯正则化神经网络分析

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108530

Taseer Muhammad , Tasawar Abbas , Zeeshan Ali , Ahmed M. Zidan , Faisal Nazir

Hybrid nanofluids have lately received extensive interest due to its excellent lubrication and heat transfer properties in engineering. In this paper, a Bayesian Regularization Neural Network (BRNN) analysis of the thermal and material transport in the hybrid nanofluid flow through a lubricated stretchable surface with a power-law lubricant layer under the impacts of a magnetic field is conducted. The study will be motivated on the joint role of magnetic field magnitude, power-law rheological behavior, nanoparticle concentration, Brownian motion, thermophoresis, and temperature-dependent thermal conductivity on the velocity, temperature, and concentration patterns in the flow. Governing equations that describe the continuity of mass, momentum, energy, and concentration, and interfacial shear stress continuity, as well as slip/no-slip boundary conditions, are used to indicate realistic physical behavior. The BRNN approach to solving the nonlinear coupled equations gives stable and accurate solutions with a high level of generalization and is checked against the Legendre Wavelet-Based Spectral Collection Method (LW-SCM). The computed outcomes imply that power-law lubricant and magnetic induction can be applied readily to increase the thermal energy transfer and decrease flow resistance, and the inclusion of nanoparticles can increase thermal transmission rate and save energy. This study’s results have shown that neural network-based methods can be used to model complex hybrid nanofluid systems and bear practical implications in micro-lubrication and thermal management, and energy conversion technologies.

混合纳米流体由于其优异的润滑和传热性能在工程上受到了广泛的关注。本文利用贝叶斯正则化神经网络（BRNN）分析了混合纳米流体在磁场作用下流经具有幂律润滑层的润滑可拉伸表面时的热输运和物质输运。这项研究的动机是磁场大小、幂律流变行为、纳米颗粒浓度、布朗运动、热泳动和温度相关的导热性对流动中的速度、温度和浓度模式的共同作用。描述质量、动量、能量和浓度连续性的控制方程，以及界面剪切应力连续性，以及滑移/无滑移边界条件，用于指示真实的物理行为。求解非线性耦合方程的BRNN方法具有稳定、精确的解，具有较高的泛化水平，并与基于Legendre小波的光谱收集方法（LW-SCM）进行了比较。计算结果表明，幂律润滑剂和磁感应可以很容易地增加热传递和降低流动阻力，纳米颗粒的包合可以提高热传递率和节约能源。这项研究的结果表明，基于神经网络的方法可以用来模拟复杂的混合纳米流体系统，并在微润滑、热管理和能量转换技术方面具有实际意义。

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引用次数: 0

International Advisory Board 国际咨询委员会

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/S2211-3797(25)00436-X

引用次数: 0

High-efficiency broadband achromatic orbital-angular-momentum metalens for focusing and edge-enhanced imaging in mid-wavelength infrared 用于中波长红外聚焦和边缘增强成像的高效宽带消色差轨道角动量超透镜

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108536

Yijie Luo , Kai Ou , Zining Wang , Kaifan Li , Siyu Dong , Jingyuan Zhu , Peng Wang , Yuchao Wang , Xiong Dun , Zeyong Wei

Edge-enhanced detection based on spiral phase contrast imaging driven by orbital angular momentum (OAM) of light, offers a promising way to obtain low-light-level signals. However, the existing OAM elements have severe restrictions on compatibility with chip-scale miniature systems operation at wide bandwidth, due to bulky configurations and chromatic dispersion. Here, we propose a general and high-efficiency achromatic focusing methodology for broadband generation of photonic OAM based on all-dielectric heterojunction metasurfaces. The innovative concept is rooted in the proposed semi-analytical multi-layer films model for control of phase dispersion via the heterojunction metasurface. For the proof of concept, we have implemented broadband achromatic and diffraction-limited focusing with the efficiency up to 70 % across the wide bandwidth ranging from 3 to 5 μm. Based on the high-efficiency achromatism, we have achieved the generation of broadband achromatic focusing optical vortex carrying a topological charge of l = 1. Finally, the OAM-based broadband achromatic meta-device successfully performs the achromatic edge-enhanced imaging. The proposed OAM-based broadband achromatic metalens, with its compact design and high efficiency, serves as a promising foundation for advancements in biomedical imaging and mid-wavelength infrared night vision technologies.

基于光的轨道角动量驱动的螺旋相衬成像边缘增强检测为获取微光信号提供了一种很有前途的方法。然而，由于结构庞大和色散，现有的OAM元件在与宽带宽下运行的芯片级微型系统的兼容性方面存在严重限制。在此，我们提出了一种基于全介电异质结超表面的宽带光子OAM的通用高效消色差聚焦方法。这个创新的概念是植根于提出的半解析多层膜模型，通过异质结超表面来控制相色散。为了验证概念，我们实现了宽带消色差和衍射限制聚焦，在3至5 μm的宽带宽范围内，效率高达70%。基于高效消色差，我们实现了带l = 1拓扑电荷的宽带消色差聚焦光学涡旋的产生。最后，基于oam的宽带消色差元器件成功实现了消色差边缘增强成像。所提出的基于oam的宽带消色差超透镜具有紧凑的设计和高效率，为生物医学成像和中波长红外夜视技术的发展奠定了良好的基础。

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引用次数: 0

Plasmomechanical actuation at the nanoscale activated by NIR radiation 近红外辐射激活的纳米级等离子体机械驱动

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108529

Daniyal Khosh Maram , Xavier Borrisé , Joan Garcia-Garcia , Xavier Cartoixà , Gabriel Abadal

The design of a plasmomechanical actuator based on an optical nanodipole antenna integrated in the overlapped free moving end of two micro-nanocantilevers is presented here. The static steady state deflection of the cantilevers, which defines the actuator response, is produced by means of two transduction phenomena activated by a continuous power NIR illumination: a desired opto-electromechanical (OEM) mechanism, in which the cantilevers are mutually attracted directly by the electrostatic force induced in the nanodipole feed gap, and a non-desired parasitic opto-thermomechanical (OTM) mechanism associated to the bimetallic effect induced by the optical heating of the structure. COMSOL Multiphysics has been chosen to carry out a design of the actuator based on an optimized optical response of the nanodipole antenna to the 1.55 μm wavelength radiation. COMSOL simulations have been also performed to evaluate the parasitic OTM response and the responsivity, defined as the OEM signal per unit radiation power. Predicted responsivity values of 0.67 nm/mW are of the same order of magnitude as in similar state-of-the-art transducers.

本文设计了一种基于光学纳米偶极子天线的等离子体机械驱动器，该天线集成在两个微纳反杆的重叠自由运动端。悬臂梁的静态稳态挠度定义了致动器的响应，它是由连续功率近红外照明激活的两种转导现象产生的：一种理想的光电（OEM）机制，其中悬臂梁被纳米偶极子馈入间隙中诱导的静电力直接相互吸引；另一种非理想的寄生光电（OTM）机制，与结构的光学加热诱导的双金属效应相关。基于纳米偶极子天线对1.55 μm波长辐射的优化光学响应，选择COMSOL Multiphysics进行了致动器设计。还进行了COMSOL模拟，以评估寄生OTM响应和响应度（定义为每单位辐射功率的OEM信号）。预测的响应度值为0.67 nm/mW，与同类最先进的传感器具有相同的数量级。

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引用次数: 0

Manipulation of thermal conductivity and thermoelectric power factor via Hf-doping in FeNbSb half-Heusler alloys for enhanced thermoelectric figure of merit 通过hf掺杂控制FeNbSb半heusler合金的热导率和热电功率因数以提高热电性能

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108538

Norah Alsairy , A.M. Adam , Z.M.H. El-Qahtani , P. Petkov , A. El-Khouly

Bulk samples of FeNb_1-xHf_xSb (x = 0.0, 0.10, 0.20) alloys have been prepared by successive induction melting and mechanical alloying (MA). Electrical and thermoelectrical characteristics have been investigated as functions of temperature in the temperature range 300 to 800 K. Electrical conductivity of the parent FeNbSb alloy and the low doped FeNb_0.9Hf_0.1Sb samples showed semiconducting behaviour with smaller electrical conductivity values. On the other hand, the most doped FeNb_0.8Hf_0.2Sb alloys showed a metal-like trend. The metallic behaviour indicated that typical acoustic phonon scattering dominates the charge transfer. Thermopower measurements revealed that Seebeck coefficients increase remarkably with the temperature increasing due to Hf-doping at the studied doping range due to the remarkable effect of Hf-doping on the carrier concentration. The relationship between temperature and thermoelectric power factor was evaluated and investigated. High thermoelectric power factor was achieved at 20 µWcm⁻¹ K⁻² for the highest Hf-doped alloy. Defects and electron–phonon scatterings reduced the lattice thermal conductivity and consequently improved thermoelectric figure of merit (zT). zT has significantly increased with temperature increasing providing evidence that half-Heusler materials are promising thermoelectric options in the mid to high temperature range. In addition, it can be concluded that higher Hf-content as dopant can simultaneously optimizes enhanced power factor besides significantly reduced thermal conductivity leading to better thermoelectric figure of merit. The maximum figure of merit (zT) was observed for the same sample with a value of 0.17, recorded at 700 K.

采用连续感应熔炼和机械合金化法制备了FeNb1-xHfxSb （x = 0.0, 0.10, 0.20）合金样品。电学和热电特性作为温度的函数在300至800 K的温度范围内进行了研究。母体FeNbSb合金和低掺杂FeNb0.9Hf0.1Sb样品的电导率表现为半导体行为，电导率值较小。另一方面，掺量最多的FeNb0.8Hf0.2Sb合金表现出金属样的趋势。金属行为表明，典型的声子散射主导了电荷转移。热功率测量表明，在研究的掺杂范围内，由于hf掺杂对载流子浓度的显著影响，Seebeck系数随着温度的升高而显著增加。对温度与热电功率因数之间的关系进行了评价和研究。在20µWcm−1 K−2时，最高掺hf的合金获得了高热电功率因数。缺陷和电子-声子散射降低了晶格热导率，从而提高了热电优值（zT）。zT随着温度的升高而显著增加，这证明半赫斯勒材料在中高温范围内是有前途的热电选择。此外，可以得出结论，较高的hf含量作为掺杂剂可以在显著降低导热系数的同时优化增强的功率因数，从而获得更好的热电优值。在700 K时，观察到同一样品的最大品质值（zT）为0.17。

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引用次数: 0

Gain superposition and thermal management optimization in high pump power lasers using tandem Nd:MgO:LiNbO3 crystals 使用Nd:MgO:LiNbO3晶体的高泵浦功率激光器的增益叠加和热管理优化

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108534

Chengfeng Liu, Xiaotian Lei, Liwan Wu, Xiaodai Yao, Hang Liu, Zijian Wang, Yongji Yu

This paper presents a tandem dual Nd:MgO:LN laser system employing a dual-end thermally boosted pumping scheme to improve thermal management under high pump power conditions. Based on theoretical studies of pump reabsorption and gain superposition effects, a laser dynamical model for the dual-crystal structure is established, simulating the temporal evolution of intracavity photon density and population inversion density to optimize resonator parameters. A three-dimensional thermal conduction model further confirms that this configuration mitigates thermal effects in the gain medium. Experimentally, at an absorbed pump power of 45.05 W, the system delivers 7.59 W of single-wavelength 1084 nm output while fully suppressing 1093 nm lasing, achieving an optical-to-optical conversion efficiency of 16.85 %, and a power stability of 0.37 % (RMS). The beam quality is M² _X = 1.56 and M² _Y = 1.59. The dual-crystal tandem design addresses thermal limitations in single-crystal structures, extending the operational power range from 34.78 W to 45.05 W while maintaining stable 1084 nm emission. The gain superposition effect contributes to enhanced output power performance. This study provides an effective approach for thermal management and gain optimization in Nd:MgO:LN crystal laser systems under high pump power conditions.

本文提出了一种双端双Nd:MgO:LN激光系统，采用双端热推进泵浦方案，以改善高泵浦功率条件下的热管理。在对泵浦重吸收和增益叠加效应进行理论研究的基础上，建立了双晶结构的激光动力学模型，模拟了腔内光子密度和居群反转密度的时间演化，优化了谐振腔参数。三维热传导模型进一步证实，这种结构减轻了增益介质中的热效应。实验结果表明，在吸收泵浦功率为45.05 W的情况下，该系统在完全抑制1093 nm激光的情况下，可输出7.59 W的1084 nm单波长输出，光-光转换效率为16.85%，功率稳定性为0.37% （RMS）。光束质量为M2 X = 1.56, M2 Y = 1.59。双晶串联设计解决了单晶结构的热限制，将工作功率范围从34.78 W扩展到45.05 W，同时保持稳定的1084 nm发射。增益叠加效应有助于提高输出功率性能。该研究为高泵浦功率条件下Nd:MgO:LN晶体激光系统的热管理和增益优化提供了有效的方法。

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引用次数: 0

Comparative study on polaronic quantum confinement effects in wurtzite ZnO and GaN nanowires under external fields 外场作用下纤锌矿ZnO和GaN纳米线中极化子量子约束效应的比较研究

IF 4.6 2区物理与天体物理 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Results in Physics

Pub Date : 2025-12-01 DOI: 10.1016/j.rinp.2025.108535

Anna Asatryan , Arshak Vartanian , Serob Hayrapetyan , Tigran Ghukasyan , Artak Avetisyan , Ya-Hong Xie

A comparative study of polaron phenomena in wurtzite-structured ZnO and GaN nanowires was conducted. The study considered the features of the phonon spectrum and electron–phonon interaction for a polar cylindrical nanowire in a non-polar medium influenced by external electric and magnetic fields. The Fröhlich polaron self-energy and the polaronic correction to the effective mass of the electron were investigated using the Lee–Low–Pines transformation method. Considering the differences in the polarities of ZnO and GaN nanowires, the contributions of quasi-confined and interface optical phonon modes to the polaron basic parameters have been studied depending on the strength of the external fields. The results obtained and their justifications can be significant for controlling polaron dynamics through the nanowire radius and the strengths of the external fields. To the best of our knowledge, this is the first comparative study addressing the polaron properties in ZnO and GaN nanowires under external electric and magnetic fields.

对纤锌矿结构ZnO和GaN纳米线中的极化子现象进行了比较研究。研究了非极性介质中受外加电场和磁场影响的极性圆柱形纳米线的声子谱和电子-声子相互作用特征。利用Lee-Low-Pines变换方法研究了Fröhlich极化子自能和电子有效质量的极化子修正。考虑到ZnO和GaN纳米线的极性差异，研究了准受限光声子模式和界面光声子模式随外场强度的变化对极化子基本参数的贡献。所得结果对通过纳米线半径和外场强度控制极化子动力学具有重要意义。据我们所知，这是第一次对外部电场和磁场下ZnO和GaN纳米线的极化子特性进行比较研究。

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引用次数: 0