Journal of Physics D: Applied Physics最新文献_第5页

EM optimization of microwave filter based on long short-term memory–feedforward neural network and transfer functions 基于长短期记忆前馈神经网络和传递函数的微波滤波器电磁优化

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad6fb1

Xin Zhang, Jian Wu, Yong-Qiang Chai, Shui Liu, Yuan Peng

{"title":"EM optimization of microwave filter based on long short-term memory–feedforward neural network and transfer functions","authors":"Xin Zhang, Jian Wu, Yong-Qiang Chai, Shui Liu, Yuan Peng","doi":"10.1088/1361-6463/ad6fb1","DOIUrl":"https://doi.org/10.1088/1361-6463/ad6fb1","url":null,"abstract":"An electromagnetic optimization technique based on a long short-term memory–feedforward neural network (LSTM-FNN) and transfer functions is proposed for microwave filter design. The proposed optimization method addresses the situation where a neuro-transfer function model repeatedly trains at each optimization iteration process. The proposed surrogate model combines the LSTM-FNN and polynomial model to map nonlinear relationships between geometric variables and transfer functions. Firstly, by combining the gate mechanism of LSTM with the high generalization ability of an FNN, the proposed LSTM-FNN effectively learns nonlinear relationships between geometric variables and frequency responses at specific frequencies. Secondly, the transfer functions can be accurately approximated via polynomial fitting. Frequency responses at any interesting frequency range can be accurately expressed using the transfer functions. Finally, the trained surrogate model, exploiting the trust-region algorithm, can accurately and efficiently achieve optimization convergence. An example of a low-pass filter (LPF) is adopted to validate the proposed optimization method.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"35 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Reconfigurable THz leaky-wave antennas based on innovative metal–graphene metasurfaces 基于创新金属石墨烯元表面的可重构太赫兹漏波天线

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad7302

Edoardo Negri, Walter Fuscaldo, Paolo Burghignoli, Alessandro Galli

引用次数: 0

Mediating coherent acoustic phonon oscillation of a 2D semiconductor/3D dielectric heterostructure by interfacial engineering 通过界面工程调节二维半导体/三维电介质异质结构的相干声子振荡

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad70c4

Wenxiong Xu, Feiyang Hou, He Zhang, Chuansheng Xia, Zhixuan Li, Yuanyuan Li, Chunxiang Xu, Qiannan Cui

{"title":"Mediating coherent acoustic phonon oscillation of a 2D semiconductor/3D dielectric heterostructure by interfacial engineering","authors":"Wenxiong Xu, Feiyang Hou, He Zhang, Chuansheng Xia, Zhixuan Li, Yuanyuan Li, Chunxiang Xu, Qiannan Cui","doi":"10.1088/1361-6463/ad70c4","DOIUrl":"https://doi.org/10.1088/1361-6463/ad70c4","url":null,"abstract":"Coherent acoustic phonon (CAP) oscillation of a 2D layered semiconductor/3D dielectric heterostructure generated by femtosecond laser pulse excitation can realize ultrafast photoacoustic conversion by emitting picosecond acoustic (PA) pulse; however, the photoacoustic conversion efficiency suffers from interfacial phonon scattering of simultaneously laser-induced lattice heat. Here, taking advantage of graphene’s high thermal conductivity and large acoustic impedance, we demonstrate that phonon scattering can be markedly mediated in a MoS2/graphene/glass heterostructure via femtosecond laser pump–probe measurements. The equilibrium temperatures of the MoS2 lattice have been cooled down by about 45%. As a benefit, both the lifetime of CAP oscillations and the pump pulse-picosecond acoustic pulse energy conversion efficiency have been enhanced by a factor of about 2. Our results offer insights into CAP and PA pulse manipulations via interfacial engineering that are fundamentally important for ultrafast photoacoustics based on 2D layered semiconductors.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"5 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Enhancing n-type doping in diamond by strain engineering 通过应变工程增强金刚石中的 n 型掺杂

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad7270

Chunmin Cheng, Xiang Sun, Wei Shen, Qijun Wang, Lijie Li, Fang Dong, Kang Liang, Gai Wu

{"title":"Enhancing n-type doping in diamond by strain engineering","authors":"Chunmin Cheng, Xiang Sun, Wei Shen, Qijun Wang, Lijie Li, Fang Dong, Kang Liang, Gai Wu","doi":"10.1088/1361-6463/ad7270","DOIUrl":"https://doi.org/10.1088/1361-6463/ad7270","url":null,"abstract":"The utilization of diamond, the ultimate semiconductor, in electronic devices is challenging due to the difficulty of n-type doping. Phosphorus (P)-doped diamond, the most prevalent type of n-type diamond, is still limited by the low solubility of P dopant and undesirable compensating defects such as vacancy defects and hydrogen incorporation. In order to overcome this limitation, strain engineering is introduced to the n-type P-doped diamond theoretically in this work. Uniaxial, equibiaxial, and hydrostatic triaxial strains are applied to the P-doped diamond. The formation energy, charge transition level, defect binding energy and other physical properties of the P-doped diamond are then calculated based on first-principles calculations. The results show that uniaxial, equibiaxial, and hydrostatic triaxial tensile strain can reduce the formation energy and the donor ionization energy of P dopant, and also reduce the binding energy of phosphorus–vacancy (PV) and phosphorus–hydrogen (PH) defects. Our results indicate that under tensile strain, the solubility of the P dopant and the n-type conductivity of the P-doped diamond can be increased, and the formation of compensating defects can be suppressed. Therefore, strain engineering is anticipated to be used to enhance the n-type characteristics of the P-doped diamond, facilitating its application in electronic devices.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"29 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Defect engineering strategies in monolayer VSe2 for enhanced hydrogen evolution reaction: a computational study 用于增强氢气进化反应的单层 VSe2 缺陷工程策略：计算研究

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad73e3

Rabia Hassan, Fei Ma, Yan Li, Rehan Hassan

引用次数: 0

Label-free characterization of pathological changes in the portal area of liver fibrosis tissue using multiphoton imaging and quantitative image analysis 利用多光子成像和定量图像分析对肝纤维化组织门区病理变化进行无标记表征

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-05 DOI: 10.1088/1361-6463/ad73e6

Xiong Zhang, Yuan-E Lian, XunBin Yu, Xingxin Huang, Zheng Zhang, Jingyi Zhang, Jianxin Chen, Lianhuang Li, Yannan Bai

{"title":"Label-free characterization of pathological changes in the portal area of liver fibrosis tissue using multiphoton imaging and quantitative image analysis","authors":"Xiong Zhang, Yuan-E Lian, XunBin Yu, Xingxin Huang, Zheng Zhang, Jingyi Zhang, Jianxin Chen, Lianhuang Li, Yannan Bai","doi":"10.1088/1361-6463/ad73e6","DOIUrl":"https://doi.org/10.1088/1361-6463/ad73e6","url":null,"abstract":"Liver fibrosis plays a crucial role in the progression of liver diseases and serves as a pivotal stage leading to the development of liver cirrhosis and cancer. It typically initiates from portal area with various pathological characteristics. In this article, we employed multiphoton microscopy (MPM) to characterize the pathological changes in the portal areas of liver fibrosis tissues, and subsequently, we used our developed image analysis method to extract eight collagen morphological features from MPM images and also combined a deep learning method with a cell nuclear feature extraction algorithm to perform automatic nuclei segmentation and quantitative analysis in the H&E-stained histopathology images of portal areas. Our results demonstrate that MPM can effectively identify various pathological features in portal areas, and there are significant differences in four collagen features (collagen proportionate area, number, length and width) between normal and abnormal portal areas and in four nuclear features (mean ratio of axial length, disorder of distance to 3, 5 and 7 nearest neighbors) between normal portal area, bile duct hyperplasia and periductal fibrosis. Therefore, a combination of MPM and image-based quantitative analysis may be considered as a rapid and effective means to monitor histopathological changes in portal area and offer new insights into liver fibrosis.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"5 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Electrically-driven IMT and volatile memristor behavior in NdNiO3 films NdNiO3 薄膜中的电驱动 IMT 和挥发性记忆晶体行为

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-04 DOI: 10.1088/1361-6463/ad714e

O D Schneble, I A Leahy, J D Zimmerman, M B Tellekamp

{"title":"Electrically-driven IMT and volatile memristor behavior in NdNiO3 films","authors":"O D Schneble, I A Leahy, J D Zimmerman, M B Tellekamp","doi":"10.1088/1361-6463/ad714e","DOIUrl":"https://doi.org/10.1088/1361-6463/ad714e","url":null,"abstract":"Transition metal oxides with insulator-metal transitions (IMTs) are uniquely suited for volatile memristor devices that mimic the spiking of biological neurons. Unlike most non-volatile memristors, which often operate via ion migration into filaments, volatile devices utilize a reversible phase change that returns to a ground state in the absence of applied stimulus. In these devices, Joule heating triggers the IMT and changes the bulk resistivity rather than influencing conduction through defects, as in previous studies. This volatile resistive switching behavior has previous been leveraged in niobium and vanadium oxides, but not in rare-earth nickelates, despite their tunable transition temperatures. This study demonstrates an electrically driven IMT in the prototypical rare-earth nickelate, NdNiO3, in large area devices. While previous work examining the electrically-driven IMT in NdNiO3 suggests defect-dominated conduction, this study shows clear s-type negative differential resistance (NDR) consistent with temperature-dependent resistivity measurements. The NDR peak-to-valley voltage scales linearly with temperature as expected for conductivity pathways dominated by bulk IMT behavior. Unlike other transition metal oxides, which are modeled using the insulator-metal phase fraction as the internal state variable, a thermoelectric model with temperature as the internal state variable is found to more accurately describe the current–voltage characteristic of NdNiO3 volatile memristors. Overall, we report the synthesis, fabrication, and characterization of NdNiO3 volatile memristors with resistivity dominated by bulk-like IMT behavior which is scalable and not dependent upon oxygen vacancy migration or defect mediated conduction pathways.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"7 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

In-situ and ex-situ characterizations of PVT-grown 4H-SiC single crystals PVT 生长的 4H-SiC 单晶的原位和离位表征

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-03 DOI: 10.1088/1361-6463/ad7149

Qinqin Shao, Ruohan Shen, He Tian, Xiaodong Pi, Deren Yang, Rong Wang

{"title":"In-situ and ex-situ characterizations of PVT-grown 4H-SiC single crystals","authors":"Qinqin Shao, Ruohan Shen, He Tian, Xiaodong Pi, Deren Yang, Rong Wang","doi":"10.1088/1361-6463/ad7149","DOIUrl":"https://doi.org/10.1088/1361-6463/ad7149","url":null,"abstract":"4H silicon carbide (4H-SiC) is one of the most promising candidates in high-power and high-frequency devices, owing to its excellent properties such as wide bandgap, high electron mobility, high electric breakdown field and high thermal conductivity. The physical-vapor-transport (PVT) approach has been broadly adopted to grow 4H-SiC single-crystal boules. Because of the high-temperature growth of 4H-SiC single-crystal boules, the PVT system is a ‘black-box’ system, which decreases the yield and thus increases the cost of 4H-SiC single-crystals. Although advanced modern characterization tools, e.g. atomic force microscopy, <italic toggle=\"yes\">x</italic>-ray topography, x-ray diffraction and Raman scattering spectroscopy, can provide deep insight into the structural and defect properties of 4H-SiC boules, it is rather limited to gain <italic toggle=\"yes\">in-situ</italic> information of the growth process by these <italic toggle=\"yes\">ex-situ</italic> methods. Therefore, the <italic toggle=\"yes\">in-situ</italic> visualization on the evolution of structural morphologies and defects conducted by <italic toggle=\"yes\">x</italic>-ray computed tomography (<italic toggle=\"yes\">x</italic>CT) is of great importance for further development. In this topical review, the application of the <italic toggle=\"yes\">x</italic>CT technology on the <italic toggle=\"yes\">in-situ</italic> visualization of the evolution of the growth front, growth rate, defects, and the mass transport of the source material of 4H-SiC are reviewed. The <italic toggle=\"yes\">ex-situ</italic> characterization of 4H-SiC single-crystal boules are also briefly introduced. This topical review provides insight into the growth process, structural morphology, and defect evolution of PVT-grown 4H-SiC single-crystal boules.","PeriodicalId":16789,"journal":{"name":"Journal of Physics D: Applied Physics","volume":"29 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Recent advances in molecular dynamics simulations for dry friction on rough substrate 粗糙基底干摩擦分子动力学模拟的最新进展

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-03 DOI: 10.1088/1361-6463/ad6e00

Yan Zhang, Zhaofu Zhang, Yuzheng Guo, John Robertson, Shijing Wu, Sheng Liu, Yunyun Sun

引用次数: 0

Single-crystal silicon ablation with temporally delayed femtosecond laser double-pulse trains 利用时延飞秒激光双脉冲序列烧蚀单晶硅

IF 3.4 3区物理与天体物理

Journal of Physics D: Applied Physics Pub Date : 2024-09-03 DOI: 10.1088/1361-6463/ad7300

Zhengjie Fan, Liangtian Yi, Jing Lv, Wenjun Wang, Guoji Li, Jianlei Cui

引用次数: 0