Yuan Yang, Keli Gao, Hao Wang, Shuai Yuan, Jinchao Du, Yansong Ji, Dehui Fu, Yin Huang, Guangkai Cui
C4F7N/CO2 gas mixture, as the main new environmentally friendly gas insulation medium, is now being widely used in the ring network switchgear and other gas electrical equipment. In this paper, a test platform was constructed to simulate partial discharge in a gas medium, the decomposition characteristics of the C4F7N/CO2 gas mixture during suspended potential discharge were studied under four different metal electrode materials: stainless steel, purple copper, tungsten copper, and aluminum alloy. The results show that the main decomposition products of the C4F7N/CO2 gas mixture during suspended discharge are CO, CF4, C4F8, C3F8, C3F6, CF3CN, and C2F4 gases, which are independent of the metal material. On the whole, when the metal electrode material is stainless steel, the highest amount of decomposition products are generated from the C4F7N/CO2 gas mixture; when the metal electrode material is aluminum alloy, the amount of decomposition products produced by C4F7N/CO2 gas mixture is the least, and the content difference of some decomposition products between these two metal materials is as high as 70%. The decomposition products of the C4F7N/CO2 gas mixture decreased gradually with the increase in the gas pressure. Finally, the influence mechanism of different metal materials on the decomposition process of the C4F7N/CO2 gas mixture was analyzed from the microscopic perspectives of charge transfer between gas molecules and molecular structural characteristics. In general, the research results can provide technical reference for the design, selection, and optimization of environmental protection gas insulation equipment.
{"title":"Decomposition characteristics and influencing mechanisms of C4F7N/CO2 gas with different metal materials","authors":"Yuan Yang, Keli Gao, Hao Wang, Shuai Yuan, Jinchao Du, Yansong Ji, Dehui Fu, Yin Huang, Guangkai Cui","doi":"10.1063/5.0214100","DOIUrl":"https://doi.org/10.1063/5.0214100","url":null,"abstract":"C4F7N/CO2 gas mixture, as the main new environmentally friendly gas insulation medium, is now being widely used in the ring network switchgear and other gas electrical equipment. In this paper, a test platform was constructed to simulate partial discharge in a gas medium, the decomposition characteristics of the C4F7N/CO2 gas mixture during suspended potential discharge were studied under four different metal electrode materials: stainless steel, purple copper, tungsten copper, and aluminum alloy. The results show that the main decomposition products of the C4F7N/CO2 gas mixture during suspended discharge are CO, CF4, C4F8, C3F8, C3F6, CF3CN, and C2F4 gases, which are independent of the metal material. On the whole, when the metal electrode material is stainless steel, the highest amount of decomposition products are generated from the C4F7N/CO2 gas mixture; when the metal electrode material is aluminum alloy, the amount of decomposition products produced by C4F7N/CO2 gas mixture is the least, and the content difference of some decomposition products between these two metal materials is as high as 70%. The decomposition products of the C4F7N/CO2 gas mixture decreased gradually with the increase in the gas pressure. Finally, the influence mechanism of different metal materials on the decomposition process of the C4F7N/CO2 gas mixture was analyzed from the microscopic perspectives of charge transfer between gas molecules and molecular structural characteristics. In general, the research results can provide technical reference for the design, selection, and optimization of environmental protection gas insulation equipment.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"192 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Shunmathi M., Julius Fusic S., Shanmugavel Rajesh, Jayant Giri, Sathish T., Abdullah Alarifi, S. M. Mozammil Hasnain
The focus of this scope is on the single phase Cuk and SEPIC power factor correction converter that is attractive to electric bicycle applications. In order to guarantee improved performance, the proposed modified converter is designed to operate in discontinuous conduction mode, which is hidden by changes in supply and load voltage. For rated load, the investigational study achieves reduced input line total harmonic distortion and unity power factor. Line regulation, high efficiency, and load regulation are achieved by means of a closed loop PI control circuit that has a voltage sensor and current loop. The power supply is simulated using MATLAB/Simulink under various operating conditions, and the designed system is validated using a 250 W hardware prototype. The input current is observed to be perfectly sinusoidal, and the IEC 61000-3-2 class A standard is followed in recording the total harmonic distortion of the mains current.
本研究的重点是对电动自行车应用具有吸引力的单相 Cuk 和 SEPIC 功率因数校正转换器。为了保证性能的提高，所提出的改进型转换器被设计为在不连续传导模式下运行，这种模式不受电源和负载电压变化的影响。在额定负载情况下，调查研究降低了输入线路总谐波失真和功率因数。线路调节、高效率和负载调节是通过具有电压传感器和电流环路的闭环 PI 控制电路实现的。使用 MATLAB/Simulink 对各种工作条件下的电源进行了仿真，并使用 250 W 硬件原型对所设计的系统进行了验证。观察到输入电流为完全正弦波，并按照 IEC 61000-3-2 A 级标准记录了电源电流的总谐波失真。
{"title":"Bridgeless modified Cuk–SEPIC power factor correction converter for E-bicycle applications","authors":"Shunmathi M., Julius Fusic S., Shanmugavel Rajesh, Jayant Giri, Sathish T., Abdullah Alarifi, S. M. Mozammil Hasnain","doi":"10.1063/5.0229333","DOIUrl":"https://doi.org/10.1063/5.0229333","url":null,"abstract":"The focus of this scope is on the single phase Cuk and SEPIC power factor correction converter that is attractive to electric bicycle applications. In order to guarantee improved performance, the proposed modified converter is designed to operate in discontinuous conduction mode, which is hidden by changes in supply and load voltage. For rated load, the investigational study achieves reduced input line total harmonic distortion and unity power factor. Line regulation, high efficiency, and load regulation are achieved by means of a closed loop PI control circuit that has a voltage sensor and current loop. The power supply is simulated using MATLAB/Simulink under various operating conditions, and the designed system is validated using a 250 W hardware prototype. The input current is observed to be perfectly sinusoidal, and the IEC 61000-3-2 class A standard is followed in recording the total harmonic distortion of the mains current.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"37 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
This study investigates leakage mechanisms in vertical GaN-on-GaN Schottky barrier diodes (SBDs) and demonstrates effective mitigation strategies. The fabricated devices exhibit low reverse leakage current (1 × 10−5 A/cm2 at −200 V) and a high Ion/Ioff ratio (∼1010), surpassing the performance of GaN SBDs on foreign substrates. We elucidate dominant leakage mechanisms—thermionic emission, Poole–Frenkel emission, and variable-range hopping—and their evolution with temperature and bias. Optimized fabrication processes, including defect etching and a novel dual-layer passivation technique, achieve over a 1000-fold reduction in leakage current.
本研究调查了垂直氮化镓-氮化镓肖特基势垒二极管（SBD）的漏电机制，并展示了有效的缓解策略。所制备的器件具有较低的反向漏电流（-200 V 时为 1 × 10-5 A/cm2 ）和较高的离子/关断比（∼1010），其性能超过了国外衬底上的 GaN SBD。我们阐明了主要的漏电机制--热离子发射、普尔-弗伦克尔发射和变程跳变--及其随温度和偏压的演变。优化的制造工艺（包括缺陷蚀刻和新型双层钝化技术）使漏电流降低了 1000 多倍。
{"title":"Leakage current in GaN-on-GaN vertical GaN SBDs grown by HVPE on native GaN substrates","authors":"Weiyi Jin, Yumin Zhang, Songyuan Xia, Qizhi Zhu, Yuanhang Sun, Juemin Yi, Jianfeng Wang, Ke Xu","doi":"10.1063/5.0208706","DOIUrl":"https://doi.org/10.1063/5.0208706","url":null,"abstract":"This study investigates leakage mechanisms in vertical GaN-on-GaN Schottky barrier diodes (SBDs) and demonstrates effective mitigation strategies. The fabricated devices exhibit low reverse leakage current (1 × 10−5 A/cm2 at −200 V) and a high Ion/Ioff ratio (∼1010), surpassing the performance of GaN SBDs on foreign substrates. We elucidate dominant leakage mechanisms—thermionic emission, Poole–Frenkel emission, and variable-range hopping—and their evolution with temperature and bias. Optimized fabrication processes, including defect etching and a novel dual-layer passivation technique, achieve over a 1000-fold reduction in leakage current.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"6 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
The as-cast specimens of Ti48Zr18V12Cu5Be17 amorphous composites were prepared by copper mold suction casting. Next, the as-cast specimens were treated using semi-solid isothermal treatment (SSIT) and recrystallization and partial remelting (RAP). The effects of SSIT and RAP on the microstructure and plasticity were analyzed. The results showed that the microstructure changed from fine crystals in the as-cast specimens to coarse bar crystals and near-spherical crystals in the SSIT and RAP specimens, respectively. The crystals of RAP specimens were finer and rounder than those of SSIT specimens due to recrystallization. In addition, the RAP specimens had high plasticity (20.93%), which is 428.5% and 45.2% higher than the as-cast and SSIT specimens, respectively. By observing the shear bands of the fractured specimens, it was found that the expansion of shear bands could not be impeded by the fine β-Ti crystals in the as-cast specimens, leading to an infinite extension that induces brittle fracture in the specimens. The essential cause of the poor plasticity of the as-cast specimens was revealed. In addition, the coarse β-Ti crystals effectively blocked the shear band expansion in the SSIT specimens, and a large number of shear bands were generated in these crystals. In contrast, the crystals of the RAP specimens had a greater number and density of shear bands compared to those of the SSIT specimens, and these shear bands intersected with each other in different directions. This revealed the mechanism by which the SSIT and RAP methods enhance the plasticity of amorphous composites.
{"title":"Differences in microstructure and properties of Ti-based amorphous composites between recrystallization and partial remelting and semi-solid isothermal treatment","authors":"Xin-hua Huang, Jin-heng Chen, Yu-huai Wang, Yong-xin Luo, Yue-jun Ouyang","doi":"10.1063/5.0226545","DOIUrl":"https://doi.org/10.1063/5.0226545","url":null,"abstract":"The as-cast specimens of Ti48Zr18V12Cu5Be17 amorphous composites were prepared by copper mold suction casting. Next, the as-cast specimens were treated using semi-solid isothermal treatment (SSIT) and recrystallization and partial remelting (RAP). The effects of SSIT and RAP on the microstructure and plasticity were analyzed. The results showed that the microstructure changed from fine crystals in the as-cast specimens to coarse bar crystals and near-spherical crystals in the SSIT and RAP specimens, respectively. The crystals of RAP specimens were finer and rounder than those of SSIT specimens due to recrystallization. In addition, the RAP specimens had high plasticity (20.93%), which is 428.5% and 45.2% higher than the as-cast and SSIT specimens, respectively. By observing the shear bands of the fractured specimens, it was found that the expansion of shear bands could not be impeded by the fine β-Ti crystals in the as-cast specimens, leading to an infinite extension that induces brittle fracture in the specimens. The essential cause of the poor plasticity of the as-cast specimens was revealed. In addition, the coarse β-Ti crystals effectively blocked the shear band expansion in the SSIT specimens, and a large number of shear bands were generated in these crystals. In contrast, the crystals of the RAP specimens had a greater number and density of shear bands compared to those of the SSIT specimens, and these shear bands intersected with each other in different directions. This revealed the mechanism by which the SSIT and RAP methods enhance the plasticity of amorphous composites.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"65 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Ming-Chun Qi, Xiao-Song Yang, Chen Xia, San-Qiu Liu
The non-stationary Karpman–Washimi ponderomotive force and self-generated magnetic field in an unmagnetized system are investigated in the context of nonextensive distribution based on the kinetic theory. The ponderomotive force, magnetization, and radiation power are obtained as functions of the nonextensive parameter q, wave frequency, and wave number. It is shown that the presence of high-velocity electrons leads to an increase in temporal and spatial variation parts of ponderomotive force, magnetization, and radiation power. Furthermore, the results indicate that the self-generated magnetic field driven by the Karpman–Washimi ponderomotive force primarily manifests as small-scale and low-frequency magnetic field.
{"title":"Karpman–Washimi ponderomotive force and self-generated magnetic field in nonextensive plasmas","authors":"Ming-Chun Qi, Xiao-Song Yang, Chen Xia, San-Qiu Liu","doi":"10.1063/5.0228257","DOIUrl":"https://doi.org/10.1063/5.0228257","url":null,"abstract":"The non-stationary Karpman–Washimi ponderomotive force and self-generated magnetic field in an unmagnetized system are investigated in the context of nonextensive distribution based on the kinetic theory. The ponderomotive force, magnetization, and radiation power are obtained as functions of the nonextensive parameter q, wave frequency, and wave number. It is shown that the presence of high-velocity electrons leads to an increase in temporal and spatial variation parts of ponderomotive force, magnetization, and radiation power. Furthermore, the results indicate that the self-generated magnetic field driven by the Karpman–Washimi ponderomotive force primarily manifests as small-scale and low-frequency magnetic field.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"18 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Wei Chen, Qi Chen, Jianmin Zhang, Yu Zheng, Ying Long
Inspired by the fabrication of the transition metal dichalcogenide nanoribbons with well-defined atomically precise edges, we study the stability, electronic structures, and magnetism of MTe2 (M = Cr, V, and Fe) monolayer nanoribbons. The calculations indicate that all three types of monolayers can form structurally stable zigzag (ZNR) and armchair (ANR) nanoribbons, which significantly alter the properties of the monolayer films, as shown in Table I. For the zigzag nanoribbons, CrTe2-ZNR transitions from a non-magnetic semiconductor to a ferrimagnetic metal. VTe2-ZNR transforms from a ferromagnetic semiconductor to a ferrimagnetic metal. FeTe2-ZNR mostly maintains the characteristics of the monolayer. For the armchair nanoribbons, CrTe2-ANR exhibits ferrimagnetism. The electrical conductivity is related to the width. CrTe2-ANR with narrow width is semiconducting, while wider ones are metallic. VTe2-ANR displays ferromagnetic or ferrimagnetic metallic behavior depending on the width. FeTe2-ANR with widths larger than 11 remains ferromagnetic metal, while with narrow widths are unstable. In addition, the magnetism of all MTe2 monolayer nanoribbons primarily originates from the 3d transition metal atoms. These findings are essential for applications of MTe2 nanoribbons-based low-dimensional spintronic devices.
{"title":"Electronic structures and magnetism of MTe2 (M = Cr, V, and Fe) monolayer nanoribbons","authors":"Wei Chen, Qi Chen, Jianmin Zhang, Yu Zheng, Ying Long","doi":"10.1063/5.0223768","DOIUrl":"https://doi.org/10.1063/5.0223768","url":null,"abstract":"Inspired by the fabrication of the transition metal dichalcogenide nanoribbons with well-defined atomically precise edges, we study the stability, electronic structures, and magnetism of MTe2 (M = Cr, V, and Fe) monolayer nanoribbons. The calculations indicate that all three types of monolayers can form structurally stable zigzag (ZNR) and armchair (ANR) nanoribbons, which significantly alter the properties of the monolayer films, as shown in Table I. For the zigzag nanoribbons, CrTe2-ZNR transitions from a non-magnetic semiconductor to a ferrimagnetic metal. VTe2-ZNR transforms from a ferromagnetic semiconductor to a ferrimagnetic metal. FeTe2-ZNR mostly maintains the characteristics of the monolayer. For the armchair nanoribbons, CrTe2-ANR exhibits ferrimagnetism. The electrical conductivity is related to the width. CrTe2-ANR with narrow width is semiconducting, while wider ones are metallic. VTe2-ANR displays ferromagnetic or ferrimagnetic metallic behavior depending on the width. FeTe2-ANR with widths larger than 11 remains ferromagnetic metal, while with narrow widths are unstable. In addition, the magnetism of all MTe2 monolayer nanoribbons primarily originates from the 3d transition metal atoms. These findings are essential for applications of MTe2 nanoribbons-based low-dimensional spintronic devices.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"5 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
The incorporation of medical physics into the field of oncology has profoundly changed the ways in which cancer is diagnosed and treated. This article highlights the essential roles that medical physicists play in cancer care, demonstrating how principles from physics improve various aspects of oncology practices. Our analysis reveals that medical physics plays a fundamental role in optimizing various oncological procedures, thereby revolutionizing the management of cancer. Specifically, medical physicists are integral to critical areas such as radiation therapy planning, surgical navigation, and quality assurance, which collectively facilitate personalized and effective treatment strategies for patients. By working closely with healthcare professionals, medical physicists help ensure patients receive top-notch care while minimizing side effects associated with treatments. Their dedication to innovation and research is essential for improving both patient outcomes and quality of life throughout the cancer journey. The ongoing partnership between medical physicists and clinicians is instrumental in propelling advancements in oncology research and clinical practices, leveraging physics principles alongside state-of-the-art technologies to enhance cancer management. As medical physicists commit to excellence and patient-centered practices, they are at the forefront of transforming oncology care, promising improved hope and outcomes for those battling cancer. This collaborative effort ensures a bright future for cancer treatment, where the integration of physics not only optimizes therapeutic approaches but also fosters a comprehensive understanding of cancer care.
{"title":"Shaping the future of cancer treatment: The commitment of medical physicists","authors":"Marwan Al-Raeei","doi":"10.1063/5.0219314","DOIUrl":"https://doi.org/10.1063/5.0219314","url":null,"abstract":"The incorporation of medical physics into the field of oncology has profoundly changed the ways in which cancer is diagnosed and treated. This article highlights the essential roles that medical physicists play in cancer care, demonstrating how principles from physics improve various aspects of oncology practices. Our analysis reveals that medical physics plays a fundamental role in optimizing various oncological procedures, thereby revolutionizing the management of cancer. Specifically, medical physicists are integral to critical areas such as radiation therapy planning, surgical navigation, and quality assurance, which collectively facilitate personalized and effective treatment strategies for patients. By working closely with healthcare professionals, medical physicists help ensure patients receive top-notch care while minimizing side effects associated with treatments. Their dedication to innovation and research is essential for improving both patient outcomes and quality of life throughout the cancer journey. The ongoing partnership between medical physicists and clinicians is instrumental in propelling advancements in oncology research and clinical practices, leveraging physics principles alongside state-of-the-art technologies to enhance cancer management. As medical physicists commit to excellence and patient-centered practices, they are at the forefront of transforming oncology care, promising improved hope and outcomes for those battling cancer. This collaborative effort ensures a bright future for cancer treatment, where the integration of physics not only optimizes therapeutic approaches but also fosters a comprehensive understanding of cancer care.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"27 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Density functional theory-based characterization of crystalline tungsten oxide has been well established. Nonetheless, there remains a partial gap in theoretical studies concerning the electrochemical characterization of amorphous tungsten oxide. The electronic structure and diffusion kinetics of amorphous tungsten oxide require a systematic theoretical study. Therefore, we employed second-generation Car–Parrinello molecular dynamics simulations and the density functional theory with HSE06 exchange–correlation hybrid functional to investigate the electronic properties and lithium kinetics of amorphous tungsten oxide (α-WOx, x = 3, 2.5, 2) models. The precise electronic properties of these structures were computed using the HSE06 hybrid functions. The diffusion properties of lithium were determined in the range of 1 × 10−7 to 5 × 10−7 cm2/s by ab initio molecular dynamics. The computational findings provide a critical atomic-scale understanding and contribute to the development of tungsten oxide-based electrochromic devices for practical applications.
基于密度泛函理论的晶体氧化钨表征方法已经成熟。然而，关于无定形氧化钨电化学特性的理论研究仍存在部分空白。非晶态氧化钨的电子结构和扩散动力学需要系统的理论研究。因此，我们采用第二代 Car-Parrinello 分子动力学模拟和密度泛函理论与 HSE06 交换相关混合函数来研究无定形氧化钨 (α-WOx, x = 3, 2.5, 2) 模型的电子特性和锂动力学。使用 HSE06 混合函数计算了这些结构的精确电子特性。利用 ab initio 分子动力学确定了锂在 1 × 10-7 至 5 × 10-7 cm2/s 范围内的扩散特性。这些计算结果提供了关键的原子尺度理解，有助于开发基于氧化钨的电致变色器件的实际应用。
{"title":"Exploring the electronic structure and lithium diffusion kinetics of amorphous tungsten oxide","authors":"Chao Tang, Huachen Liu, Changlong Cai","doi":"10.1063/5.0229132","DOIUrl":"https://doi.org/10.1063/5.0229132","url":null,"abstract":"Density functional theory-based characterization of crystalline tungsten oxide has been well established. Nonetheless, there remains a partial gap in theoretical studies concerning the electrochemical characterization of amorphous tungsten oxide. The electronic structure and diffusion kinetics of amorphous tungsten oxide require a systematic theoretical study. Therefore, we employed second-generation Car–Parrinello molecular dynamics simulations and the density functional theory with HSE06 exchange–correlation hybrid functional to investigate the electronic properties and lithium kinetics of amorphous tungsten oxide (α-WOx, x = 3, 2.5, 2) models. The precise electronic properties of these structures were computed using the HSE06 hybrid functions. The diffusion properties of lithium were determined in the range of 1 × 10−7 to 5 × 10−7 cm2/s by ab initio molecular dynamics. The computational findings provide a critical atomic-scale understanding and contribute to the development of tungsten oxide-based electrochromic devices for practical applications.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"208 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
The magnetospheric plasma (hot and thin) and the solar wind plasma (cold and dense) are separated by the Earth’s magnetopause, in which plasmas of both origins coexist. Different types of plasma diffusions are found due to this plasma mixing, and kinetic Alfvén solitary waves (KASWs) are one of them. In this work, a theoretical approach is taken to study the fundamental properties of heavy ion acoustic KASWs (HIAKASWs) in a magnetized plasma system whose constituents are nonextensive q-distributed two temperature electrons with dynamical heavy ions. The perturbations of the magnetized collisionless plasma system are investigated using the reductive perturbation technique to deduce the Korteweg–de Vries (K–DV) and modified K–DV (MK–DV) equations to determine the fundamental characteristics of small, but finite amplitude HIAKASWs. The presence of nonextensive electrons, magnetic field, obliquity angle (the angle between the external magnetic field and wave propagation), plasma particle number densities, and the temperature of various plasma species are observed to significantly alter the fundamental properties of HIAKASWs. The findings of our present study may be useful for comprehending the nonlinear wave properties in diverse interstellar plasma environments.
{"title":"Kinetic Alfvén solitary waves in astrophysical plasmas","authors":"M. M. Hasan, M. R. Hossen, A. A. Mamun","doi":"10.1063/5.0226568","DOIUrl":"https://doi.org/10.1063/5.0226568","url":null,"abstract":"The magnetospheric plasma (hot and thin) and the solar wind plasma (cold and dense) are separated by the Earth’s magnetopause, in which plasmas of both origins coexist. Different types of plasma diffusions are found due to this plasma mixing, and kinetic Alfvén solitary waves (KASWs) are one of them. In this work, a theoretical approach is taken to study the fundamental properties of heavy ion acoustic KASWs (HIAKASWs) in a magnetized plasma system whose constituents are nonextensive q-distributed two temperature electrons with dynamical heavy ions. The perturbations of the magnetized collisionless plasma system are investigated using the reductive perturbation technique to deduce the Korteweg–de Vries (K–DV) and modified K–DV (MK–DV) equations to determine the fundamental characteristics of small, but finite amplitude HIAKASWs. The presence of nonextensive electrons, magnetic field, obliquity angle (the angle between the external magnetic field and wave propagation), plasma particle number densities, and the temperature of various plasma species are observed to significantly alter the fundamental properties of HIAKASWs. The findings of our present study may be useful for comprehending the nonlinear wave properties in diverse interstellar plasma environments.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"42 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
Phototransients are investigated for CuSbS2 films with varying the illumination energy. The generation and recombination of photocarriers, which are manifested as changes in the sheet conductivity of the films, take place almost instantaneously for excitation wavelengths of 970 and 633 nm. These rapid responses are, in contrast, absent for the illumination at wavelengths of 375 and 280 nm. In particular, roughly no photoconduction occurs in the case of 280 nm. The sheet conductivity develops thereby random two-level fluctuations following the illumination. Ultraviolet irradiation is thus suggested to generate crystalline defects, giving rise to the quenching of the instantaneous photoresponse caused by their trapping of the photocarriers. The photoresponse in simultaneous illumination at multiple wavelengths is dependent upon the relative intensities of the ultraviolet and visible/infrared components in a nonlinear fashion unless the photo-generated defects are overwhelmed by photocarriers.
{"title":"Evidence for the quenching of rapid photoresponse by defect generation in ultraviolet illumination of CuSbS2 films","authors":"Y. Takagaki","doi":"10.1063/5.0227670","DOIUrl":"https://doi.org/10.1063/5.0227670","url":null,"abstract":"Phototransients are investigated for CuSbS2 films with varying the illumination energy. The generation and recombination of photocarriers, which are manifested as changes in the sheet conductivity of the films, take place almost instantaneously for excitation wavelengths of 970 and 633 nm. These rapid responses are, in contrast, absent for the illumination at wavelengths of 375 and 280 nm. In particular, roughly no photoconduction occurs in the case of 280 nm. The sheet conductivity develops thereby random two-level fluctuations following the illumination. Ultraviolet irradiation is thus suggested to generate crystalline defects, giving rise to the quenching of the instantaneous photoresponse caused by their trapping of the photocarriers. The photoresponse in simultaneous illumination at multiple wavelengths is dependent upon the relative intensities of the ultraviolet and visible/infrared components in a nonlinear fashion unless the photo-generated defects are overwhelmed by photocarriers.","PeriodicalId":7619,"journal":{"name":"AIP Advances","volume":"15 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142252495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}
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