Journal of Applied Physics最新文献_第4页

Defect dynamics in the presence of excess energetic carriers and high electric fields in wide-gap semiconductors 宽隙半导体中存在过量高能载流子和高电场时的缺陷动力学

Journal of Applied Physics Pub Date : 2024-05-16 DOI: 10.1063/5.0203047

Andrew O’Hara, Ronald D. Schrimpf, Daniel M. Fleetwood, Sokrates T. Pantelides

{"title":"Defect dynamics in the presence of excess energetic carriers and high electric fields in wide-gap semiconductors","authors":"Andrew O’Hara, Ronald D. Schrimpf, Daniel M. Fleetwood, Sokrates T. Pantelides","doi":"10.1063/5.0203047","DOIUrl":"https://doi.org/10.1063/5.0203047","url":null,"abstract":"Irradiation of semiconductors by energetic beams generates excess electrons and holes and may cause device degradation or failure. Both gradual degradation by total ionizing radiation (TID) and sudden degradation/failure (soft/hard breakdown) by a combination of energetic heavy ions and high voltages (typically single-event effects or SEEs) are mediated by excess carriers. The role of defect dynamics in TID degradation has been adequately understood by a combination of experiments and density-functional-theory (DFT) quantum calculations, but little has been done so far to document a role for ion-induced defects in SEE. Here, we report proof-of-principle DFT calculations in a model cubic GaN system for two defect-related excess-carrier phenomena that can play a role in various forms of device degradation and failure. The first phenomenon is the existence, dynamics, and potential roles of defect-induced quasi-localized “resonant states” in the energy-band continua. These states can enhance TID-excess-carrier and hot-carrier degradation. Furthermore, they evolve and multiply during energetic-ion-induced atom recoils and defect creation (displacement damage) and can potentially serve as excess-carrier conduction paths in SEE. The second phenomenon is the conversion of isolated vacancies into nanovoids that can participate in the formation of conducting defect “nanowires” dressed by resonances or in explosive SEE hard breakdowns.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140970129","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: 0

Perspective on electrically active defects in β-Ga2O3 from deep-level transient spectroscopy and first-principles calculations 从深层次瞬态光谱和第一原理计算透视 β-Ga2O3 中的电活性缺陷

Journal of Applied Physics Pub Date : 2024-05-16 DOI: 10.1063/5.0205950

Amanda Langørgen, Lasse Vines, Y. Kalmann Frodason

{"title":"Perspective on electrically active defects in β-Ga2O3 from deep-level transient spectroscopy and first-principles calculations","authors":"Amanda Langørgen, Lasse Vines, Y. Kalmann Frodason","doi":"10.1063/5.0205950","DOIUrl":"https://doi.org/10.1063/5.0205950","url":null,"abstract":"The ultra-wide bandgap of gallium oxide provides a rich plethora of electrically active defects. Understanding and controlling such defects is of crucial importance in mature device processing. Deep-level transient spectroscopy is one of the most sensitive techniques for measuring electrically active defects in semiconductors and, hence, a key technique for progress toward gallium oxide-based components, including Schottky barrier diodes and field-effect transistors. However, deep-level transient spectroscopy does not provide chemical or configurational information about the defect signature and must, therefore, be combined with other experimental techniques or theoretical modeling to gain a deeper understanding of the defect physics. Here, we discuss the current status regarding the identification of electrically active defects in beta-phase gallium oxide, as observed by deep-level transient spectroscopy and supported by first-principles defect calculations based on the density functional theory. We also discuss the coordinated use of the experiment and theory as a powerful approach for studying electrically active defects and highlight some of the interesting but challenging issues related to the characterization and control of defects in this fascinating material.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140967714","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: 0

Machine learning aided understanding and manipulating thermal transport in amorphous networks 机器学习辅助理解和操纵非晶网络中的热传输

Journal of Applied Physics Pub Date : 2024-05-16 DOI: 10.1063/5.0200779

Changliang Zhu, Tianlin Luo, Baowen Li, Xiangying Shen, Guimei Zhu

{"title":"Machine learning aided understanding and manipulating thermal transport in amorphous networks","authors":"Changliang Zhu, Tianlin Luo, Baowen Li, Xiangying Shen, Guimei Zhu","doi":"10.1063/5.0200779","DOIUrl":"https://doi.org/10.1063/5.0200779","url":null,"abstract":"Thermal transport plays a pivotal role across diverse disciplines, yet the intricate relationship between amorphous network structures and thermal conductance properties remains elusive due to the absence of a reliable and comprehensive network’s dataset to be investigated. In this study, we have created a dataset comprising multiple amorphous network structures of varying sizes, generated through a combination of the node disturbance method and Delaunay triangulation, to fine-tune an initially random network toward both increased and decreased thermal conductance C. The tuning process is guided by the simulated annealing algorithm. Our findings unveil that C is inversely dependent on the normalized average shortest distance Lnorm connecting heat source nodes and sink nodes, which is determined by the network topological structure. Intuitively, the amorphous network with increased C is associated with an increased number of bonds oriented along the thermal transport direction, which shortens the heat transfer distance from the source to sink node. Conversely, thermal transport encounters impedance with an augmented number of bonds oriented perpendicular to the thermal transport direction, which is demonstrated by the increased Lnorm. This relationship can be described by a power law C=Lnormα, applicable to the diverse-sized amorphous networks we have investigated.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140967367","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: 0

Modification of transition pathways in polarized resonance Raman spectroscopy for carbon nanotubes by highly confined near-field light 高约束近场光改变碳纳米管偏振共振拉曼光谱的转变路径

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0204121

Yuto Fujita, Norihiko Hayazawa, Maria Vanessa Balois-Oguchi, Takuo Tanaka, Tomoko K. Shimizu

引用次数: 0

Frequency mismatch analysis of hemispherical shell resonators with both radius and thickness imperfections 具有半径和厚度缺陷的半球形外壳谐振器的频率失配分析

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0202421

Kaixin Deng, Libin Zeng, Yao Pan, Yonglei Jia, Yiming Luo, Yunfeng Tao, Jie Yuan

{"title":"Frequency mismatch analysis of hemispherical shell resonators with both radius and thickness imperfections","authors":"Kaixin Deng, Libin Zeng, Yao Pan, Yonglei Jia, Yiming Luo, Yunfeng Tao, Jie Yuan","doi":"10.1063/5.0202421","DOIUrl":"https://doi.org/10.1063/5.0202421","url":null,"abstract":"The hemispherical shell resonator (HSR) is the core element of the hemispherical resonator gyroscope (HRG), and its frequency mismatch is a key property influencing gyroscope accuracy. Investigating the mechanism of frequency mismatch is vital for improving the quality of HSRs and performance of HRGs. Midsurface radius imperfections and thickness imperfections are two principal causes of frequency mismatch, but their combined effects have rarely been discussed. This paper develops a model to comprehensively analyze the frequency mismatch of HSRs with both radius and thickness imperfections. The model derives a quantitative relation between the frequency mismatch and the two imperfections, and provides principles for evaluating dominant imperfections. To validate the model, we conduct experiments on a batch of 12 HSRs with random geometric imperfections. We apply the model in calculating the theoretical frequency mismatches of these HSRs, and the results agree well with the experimental data. The experiment also confirms that for macro-HSRs, thickness imperfections have a larger impact than radius imperfections, and the frequency mismatch is approximately linear to the fourth thickness harmonic. Our research can be a useful reference for the design and fabrication of HSRs and may open new possibilities for high-precision manufacture of HRGs.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140975479","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: 0

Near-infrared imaging of heat transfer behavior between gadolinium and fluid during magnetization/demagnetization process of magnetocaloric effect 磁致效应磁化/去磁过程中钆与流体之间热传递行为的近红外成像

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0207290

T. Nguyen, Naoto Kakuta, K. Uchida, Hosei Nagano

{"title":"Near-infrared imaging of heat transfer behavior between gadolinium and fluid during magnetization/demagnetization process of magnetocaloric effect","authors":"T. Nguyen, Naoto Kakuta, K. Uchida, Hosei Nagano","doi":"10.1063/5.0207290","DOIUrl":"https://doi.org/10.1063/5.0207290","url":null,"abstract":"This paper reports on the application of a near-infrared (NIR) imaging system for visualizing heat transfer dynamics from a bulk gadolinium (Gd) sample to the surrounding water during the magnetization/demagnetization process of the magnetocaloric effect (MCE). The suggested approach relied on the spectral variation in water absorption band at 1150 nm wavelength within the NIR spectrum. An experimental setup integrated a telecentric uniform-illumination system, a halogen lamp, and an NIR camera to enable real-time monitoring of a single magnetization and demagnetization cycle induced by an external magnetic field, which was generated by a permanent-magnet-based magnetic circuit. Two-dimensional absorbance images captured during this cycle clearly depicted the thermal energy generated by the MCE in water. Furthermore, an analysis of the thermal boundary layer and the quantification of heat transfer from Gd to water provided insights into the dynamics over time. These results indicated the potential of our NIR imaging techniques in optimizing thermal–fluid interactions within MCE systems, thereby improving the design and efficiency of magnetic refrigeration systems.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140975515","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: 0

Structural heterogeneity and plasticity of a Zr-based metallic glass modulated by high-temperature deformation 高温变形调制的锆基金属玻璃的结构异质性和可塑性

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0204346

Wenting Lu, Bo Huang, Shansi Liao, Penghua Liu, Hui Lv, Jiayi Wu, Jun Yi, Qing Wang, Gang Wang

引用次数: 0

The use of He buffer gas for moderating the plume kinetic energy during Nd:YAG-PLD growth of EuxY2−xO3 phosphor films 在 Nd:YAG-PLD 生长 EuxY2-xO3 磷光体薄膜过程中使用 He 缓冲气调节羽流动能

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0196987

Shizuka Suzuki, Takuro Dazai, T. Tokunaga, Takahisa Yamamoto, Ryuzi Katoh, M. Lippmaa, Ryota Takahashi

{"title":"The use of He buffer gas for moderating the plume kinetic energy during Nd:YAG-PLD growth of EuxY2−xO3 phosphor films","authors":"Shizuka Suzuki, Takuro Dazai, T. Tokunaga, Takahisa Yamamoto, Ryuzi Katoh, M. Lippmaa, Ryota Takahashi","doi":"10.1063/5.0196987","DOIUrl":"https://doi.org/10.1063/5.0196987","url":null,"abstract":"We have investigated the He buffer gas process of moderating the kinetic energy of the pulsed laser deposition (PLD) plume during EuxY2−xO3 phosphor film growth. When using a neodymium yttrium aluminum garnet laser for PLD thin film growth, the kinetic energy of the ablation plumes can be high enough to cause the formation of point defects in the film. The buffer gas pressure is an important process parameter in PLD film growth. We find that the presence of the He buffer gas reduces the kinetic energy of the laser deposition plume through many low-angle collisions in the gas phase by a factor of 7 without reducing the deposition rate. This is because He is much lighter than any of the elements in the plume and it does not affect the composition of the oxide films. Consequently, the resputtering of the Y2O3 film surface by the plume was significantly suppressed in the presence of the He gas moderator, leading to a decrease of the defect density in the Y2O3 films. The improvement of the film quality was verified by a systematic analysis of time-resolved photoluminescence (PL) data for EuxY2−xO3 composition–gradient films. The PL lifetime and intensity of Eu0.2Y1.8O3, which shows the highest PL intensity, increased by 13.3% and 36.4%, respectively, when the He gas moderation process was used. The He buffer gas process is applicable to the PLD growth of the other oxide materials as well, where the reduction of the kinetic energy of the plume would bring the PLD process closer to the molecular beam epitaxy growth condition.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140973771","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: 0

230-fold Enhancement of second-harmonic generation by coupled double resonances in a dolmen-type gold metasurface 多尔曼型金元表面耦合双共振的二次谐波生成增强了 230 倍

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0205205

Xiaoteng Sun, Lili Gui, Hailun Xie, Yiwen Liu, Kun Xu

{"title":"230-fold Enhancement of second-harmonic generation by coupled double resonances in a dolmen-type gold metasurface","authors":"Xiaoteng Sun, Lili Gui, Hailun Xie, Yiwen Liu, Kun Xu","doi":"10.1063/5.0205205","DOIUrl":"https://doi.org/10.1063/5.0205205","url":null,"abstract":"Optical metasurfaces, artificial planar nanostructures composed of subwavelength meta-atoms, have attracted significant attention due to their ability to tailor optical nanoscale properties, making them a versatile platform for shaping light in both linear and nonlinear regimes. This paper reports on the realization of second harmonic generation (SHG) enhancement based on a dolmen-type gold metasurface containing two resonances. Nonlinear scattering theory is employed to numerically investigate the SHG enhancement phenomenon in the resonant metasurface. The periodic dolmen-type gold metasurface introduces a diffraction coupling effect between Fano resonance and surface lattice resonance (SLR), providing strong local-field enhancement and significantly enhancing the nonlinear effect. We analyze the influence of the coupling between Fano resonance and SLR on the SHG intensity and achieve a 230-fold enhancement in SHG intensity compared to the single resonance case by adjusting the periodicity of the metasurface. The SHG-enhanced gold metasurface may find applications in sensing, imaging, optical computing, and integrated nonlinear optics.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140974935","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: 0

Enhanced second-order nonlinear susceptibility in type-II asymmetric quantum well structures II 型非对称量子阱结构中增强的二阶非线性易感性

Journal of Applied Physics Pub Date : 2024-05-15 DOI: 10.1063/5.0174179

Stephen T. Schaefer, Zheng Ju, Xiaoyang Liu, Xin Qi, Jacob B. Khurgin, Yong-Hang Zhang

{"title":"Enhanced second-order nonlinear susceptibility in type-II asymmetric quantum well structures","authors":"Stephen T. Schaefer, Zheng Ju, Xiaoyang Liu, Xin Qi, Jacob B. Khurgin, Yong-Hang Zhang","doi":"10.1063/5.0174179","DOIUrl":"https://doi.org/10.1063/5.0174179","url":null,"abstract":"Asymmetric quantum wells (AQWs) utilizing interband transitions enhance second-order susceptibility over a wide wavelength range compared to natural crystals. The nonlinear susceptibility is further enhanced in AQWs with type-II band alignment as compared to type-I band alignment, a result of the larger interband charge shift. This enhancement is demonstrated in this work by analyzing three type-I and type-II AQW designs based on the lattice-matched InP/AlGaInAs materials systems using the envelope wavefunction approximation. The calculated interband second-order susceptibility tensor elements in type-II structures range between 20 and 1.60 × 103 pm/V for nearly resonant optical rectification and difference frequency generation applications at near-infrared and terahertz wavelengths, an improvement of nearly 1 order of magnitude over the type-I structures and 1–2 orders of magnitude over natural crystals such as LiNbO3, KTiOPO4 (KTP), or GaAs. A factor of 2–3 further enhancement of the tensor elements is achieved by optimizing the well widths and band offsets of the type-II asymmetric quantum wells. The type-II structure can be implemented in other material systems spanning the longwave infrared to visible wavelengths, enhancing nonlinear susceptibility for various applications, including photonic integrated circuits.","PeriodicalId":502933,"journal":{"name":"Journal of Applied Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140974577","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: 0