arXiv: Applied Physics最新文献_第2页

Bulk electronic structure of lanthanum hexaboride (LaB6) by hard x-ray angle-resolved photoelectron spectroscopy 硬x射线角分辨光电子能谱法研究六硼化镧(LaB6)的体电子结构

arXiv: Applied Physics Pub Date : 2020-12-04 DOI: 10.1103/PhysRevMaterials.5.055002

A. Rattanachata, L. Nicolaï, H. Martins, G. Conti, M. Verstraete, M. Gehlmann, S. Ueda, Keisuke L. I. Kobayashi, I. Vishik, C. Schneider, C. Fadley, A. Gray, J. Minár, S. Nemšák

{"title":"Bulk electronic structure of lanthanum hexaboride (\u0000LaB6\u0000) by hard x-ray angle-resolved photoelectron spectroscopy","authors":"A. Rattanachata, L. Nicolaï, H. Martins, G. Conti, M. Verstraete, M. Gehlmann, S. Ueda, Keisuke L. I. Kobayashi, I. Vishik, C. Schneider, C. Fadley, A. Gray, J. Minár, S. Nemšák","doi":"10.1103/PhysRevMaterials.5.055002","DOIUrl":"https://doi.org/10.1103/PhysRevMaterials.5.055002","url":null,"abstract":"We investigate the bulk electronic structure of lanthanum hexaboride using tender-hard x-ray photoemission spectroscopy, measuring both core-level and angle-resolved valence-band spectra. We compare the La 3d core level spectrum to cluster model calculations in order to understand the bulk-like core-hole screening effects. The results show that the La 3d well-screened peak is at a lower binding energy compared to the main poorly-screened peak and the relative intensity between these peaks depends on how strong the hybridization is between La and B atoms. We show that the recoil effect, negligible in the soft x-ray regime, becomes prominent at higher kinetic energies for lighter elements, such as boron, but is still negligible for heavy nuclei, such as lanthanum. In addition, we report the bulk-like band structure of lanthanum hexaboride determined by tender-hard x-ray angle-resolved photoemission spectroscopy (HARPES). We compare HARPES experimental results to the free-electron final-state calculations and to the more precise one-step photoemission theory including matrix element and phonon excitation effects. The agreement between the features present in the experimental ARPES data and the theoretical calculations is remarkable. In addition, we consider the nature and the magnitude of phonon excitations in order to interpret HARPES experimental data measured at different temperatures and excitation energies. We demonstrate that one step theory of photoemission and HARPES experiments provide, at present, the only approach capable of probing, both experimentally and theoretically, true bulk-like electronic band structure of rare-earth hexaborides and strongly correlated materials.","PeriodicalId":8423,"journal":{"name":"arXiv: Applied Physics","volume":"67 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91367302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Analytical Design for Full-space Spatial Power Dividers Using Metagratings 全空间空间功率分压器的分析设计

arXiv: Applied Physics Pub Date : 2020-11-29 DOI: 10.1364/JOSAB.437379

Hamid Rajabalipanah, A. Abdolali

引用次数: 4

Topological slow light via coupling chiral edge modes with flatbands 通过与平带耦合手性边缘模式的拓扑慢光

arXiv: Applied Physics Pub Date : 2020-11-28 DOI: 10.1063/5.0039839

Letian Yu, Haoran Xue, Baile Zhang

引用次数: 16

Breaking voltage–bandwidth limits in integrated lithium niobate modulators using micro-structured electrodes 利用微结构电极打破集成铌酸锂调制器的电压带宽限制

arXiv: Applied Physics Pub Date : 2020-11-26 DOI: 10.1364/OPTICA.416155

P. Kharel, C. Reimer, K. Luke, Lingyan He, Mian Zhang

引用次数: 83

Acoustic imaging by three-dimensional acoustic Luneburg meta-lens with lattice columns 带点阵柱的三维吕尼堡元透镜声学成像

arXiv: Applied Physics Pub Date : 2020-11-25 DOI: 10.1063/5.0037600

Jung-Woo Kim, Seong-Jin Lee, Jun-Yeong Jo, Semyun Wang, Sang-Hoon Kim

{"title":"Acoustic imaging by three-dimensional acoustic Luneburg meta-lens with lattice columns","authors":"Jung-Woo Kim, Seong-Jin Lee, Jun-Yeong Jo, Semyun Wang, Sang-Hoon Kim","doi":"10.1063/5.0037600","DOIUrl":"https://doi.org/10.1063/5.0037600","url":null,"abstract":"A three-dimensional acoustic Luneburg lens, or acoustic Luneburg ball, has the advantage of refracting sound waves for all incident angles and concentrating higher sound pressure compared to a two-dimensional lens. A lens with a radius of 60 mm was designed with thousands of unit atoms comprising lattice columns to maintain its shape. The focusing performance of the lens was simulated using COMSOL Multiphysics, a finite element analysis program. Acoustic imaging was performed at a frequency of 10 kHz using a microphone, transducer, three-axis linear stage, and LabVIEW-based measurement program for a plastic lens made by a selective laser sintering 3D printer. The omnidirectional property was confirmed by measuring the sound pressure level while rotating the lens. The sound pressure level gain was defined to represent the frequency-dependent performance of the lens, and the maximum values were measured at approximately 20 dB and 15 dB in the numerical simulation and the experiment, respectively, at a frequency of 16 kHz. The results suggest that acoustic meta-lenses can be used for acoustic communication, imaging systems, and energy harvesting.","PeriodicalId":8423,"journal":{"name":"arXiv: Applied Physics","volume":"167 12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83346851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Compact and Tunable Forward Coupler Based on High-Impedance Superconducting Nanowires 基于高阻抗超导纳米线的紧凑可调谐正向耦合器

arXiv: Applied Physics Pub Date : 2020-11-23 DOI: 10.1103/PHYSREVAPPLIED.15.024064

M. Colangelo, Di Zhu, D. Santavicca, B. Butters, J. Bienfang, K. Berggren

引用次数: 4

Machine Learning and High-Throughput Robust Design of P3HT-CNT Composite Thin Films for High Electrical Conductivity 高导电性P3HT-CNT复合薄膜的机器学习和高通量稳健设计

arXiv: Applied Physics Pub Date : 2020-11-20 DOI: 10.26434/chemrxiv.13265288.v1

Daniil Bash, Yongqiang Cai, Vijila Chellappan, S. L. Wong, Yang Xu, Pawan Kumar, J. Tan, Anas Abutaha, J. Cheng, Y. Lim, S. Tian, D. Ren, Flore Mekki-Barrada, W. Wong, J. Kumar, Saif A. Khan, Qianxiao Li, T. Buonassisi, K. Hippalgaonkar

{"title":"Machine Learning and High-Throughput Robust Design of P3HT-CNT Composite Thin Films for High Electrical Conductivity","authors":"Daniil Bash, Yongqiang Cai, Vijila Chellappan, S. L. Wong, Yang Xu, Pawan Kumar, J. Tan, Anas Abutaha, J. Cheng, Y. Lim, S. Tian, D. Ren, Flore Mekki-Barrada, W. Wong, J. Kumar, Saif A. Khan, Qianxiao Li, T. Buonassisi, K. Hippalgaonkar","doi":"10.26434/chemrxiv.13265288.v1","DOIUrl":"https://doi.org/10.26434/chemrxiv.13265288.v1","url":null,"abstract":"Combining high-throughput experiments with machine learning allows quick optimization of parameter spaces towards achieving target properties. In this study, we demonstrate that machine learning, combined with multi-labeled datasets, can additionally be used for scientific understanding and hypothesis testing. We introduce an automated flow system with high-throughput drop-casting for thin film preparation, followed by fast characterization of optical and electrical properties, with the capability to complete one cycle of learning of fully labeled ~160 samples in a single day. We combine regio-regular poly-3-hexylthiophene with various carbon nanotubes to achieve electrical conductivities as high as 1200 S/cm. Interestingly, a non-intuitive local optimum emerges when 10% of double-walled carbon nanotubes are added with long single wall carbon nanotubes, where the conductivity is seen to be as high as 700 S/cm, which we subsequently explain with high fidelity optical characterization. Employing dataset resampling strategies and graph-based regressions allows us to account for experimental cost and uncertainty estimation of correlated multi-outputs, and supports the proving of the hypothesis linking charge delocalization to electrical conductivity. We therefore present a robust machine-learning driven high-throughput experimental scheme that can be applied to optimize and understand properties of composites, or hybrid organic-inorganic materials.","PeriodicalId":8423,"journal":{"name":"arXiv: Applied Physics","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90459399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Defect spectroscopy and non-ionizing energy loss analysis of proton and electron irradiated p-type GaAs solar cells 质子和电子辐照p型砷化镓太阳能电池的缺陷光谱和非电离能量损失分析

arXiv: Applied Physics Pub Date : 2020-11-16 DOI: 10.1063/5.0028029

C. Pellegrino, A. Gagliardi, C. Zimmermann

{"title":"Defect spectroscopy and non-ionizing energy loss analysis of proton and electron irradiated p-type GaAs solar cells","authors":"C. Pellegrino, A. Gagliardi, C. Zimmermann","doi":"10.1063/5.0028029","DOIUrl":"https://doi.org/10.1063/5.0028029","url":null,"abstract":"Admittance spectroscopy combined with non-ionizing energy loss (NIEL) analysis is shown to be a powerful tool for analyzing solar cell radiation degradation, not relying on the change of macroscopic cell parameters. GaAs component cells, representative of the middle sub-cell in Ga 0.5 In 0.5 P / GaAs / Ge solar cells, were irradiated with protons and electrons in the 0.5–3 MeV energy range. Four irradiation-induced defects are identified in the p-type base layer. The nature of each defect is assessed by analyzing the dependence of its introduction rate on the NIEL deposited by electrons in the semiconductor. The expected linear relationship is only achieved if a unique threshold energy E d is ascribed to each defect, which ranges from 9 to 38 eV. An electron NIEL with E d = 21 eV, customarily used for GaAs-based solar cell degradation analysis, is an approximation of the relative abundance of these four defects. The 21 eV value is thus a GaAs material-specific parameter, independent of the electrical device design. In addition, the type and energy of the incident particle is correlated with the relative abundance of high E d defects. The impact of each defect on the macroscopic electrical parameters of the cell, namely, the open-circuit voltage V OC, the short-circuit current density J SC, and the recombination current density J 02, is assessed with the help of a Pearson analysis. The different effectiveness of electron and proton irradiation on parameters dominated by recombination in the depleted region, such as V OC or J 02, is attributed in part to the influence of the particle recoil spectra on the defect capture cross section.","PeriodicalId":8423,"journal":{"name":"arXiv: Applied Physics","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73477838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Surface corrugated laminates as elastic grating couplers: Splitting of SV- and P-waves by selective diffraction 作为弹性光栅耦合器的表面波纹层压板:通过选择性衍射分离SV波和p波

arXiv: Applied Physics Pub Date : 2020-11-16 DOI: 10.1063/5.0037804

G. Chaplain, R. Craster

引用次数: 1

Topological Transition in Spiral Elastic Valley Metamaterials 螺旋弹性谷超材料的拓扑跃迁

arXiv: Applied Physics Pub Date : 2020-11-12 DOI: 10.1103/PHYSREVAPPLIED.15.014058

Shuaifeng Li, Jinkyu Yang

引用次数: 7