Physica Status Solidi B-basic Solid State Physics最新文献_第10页

Photoluminescence Emission Efficiency Analysis Methodology by Integrating Raman Spectroscopy of the A1(LO) and E2(high) Phonons in a GaInN/GaN Heterostructure 通过整合 GaInN/GaN 异质结构中 A1(LO)和 E2(high)声子的拉曼光谱分析方法进行光致发光发射效率分析

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-27 DOI: 10.1002/pssb.202400057

Thee Ei Khaing Shwe, Tatsuya Asaji, Ryota Kimura, Daisuke Iida, Mohammed A. Najmi, Kazuhiro Ohkawa, Yoshihiro Ishitani

{"title":"Photoluminescence Emission Efficiency Analysis Methodology by Integrating Raman Spectroscopy of the A1(LO) and E2(high) Phonons in a GaInN/GaN Heterostructure","authors":"Thee Ei Khaing Shwe, Tatsuya Asaji, Ryota Kimura, Daisuke Iida, Mohammed A. Najmi, Kazuhiro Ohkawa, Yoshihiro Ishitani","doi":"10.1002/pssb.202400057","DOIUrl":"https://doi.org/10.1002/pssb.202400057","url":null,"abstract":"Microscopic lattice vibration images of the E2(high) mode (E2H) and another mode of A1(LO) (A1L) or the higher energy branch of LO‐phonon−plasmon coupling mode (LOPC+) in a Ga0.95In0.05N film on a GaN template are obtained by Raman scattering spectroscopy using a 325 nm laser. The increase in temperature by increasing the laser power is obtained from the decrease in the energy of E2H and the theoretical formula comprising two terms based on the mode energy variation of the bulk material and the thermal strain effect. Using the obtained temperature and the energy shift of the LOPC+, the mapping images of the temperature and electron density in the x–y plane are simultaneously obtained. This image provides the spatial variation of photoluminescence (PL) emission efficiency, given as PL intensity per electron. This method enables the quantitative discussion on photo‐emission efficiency even in the regions of low or high carrier density affected by carrier transport. In the investigated area, a region with a lower PL efficiency is found despite a higher electron density and lower temperature increase than the surrounding region. This imaging analysis is feasible in integrating the carrier and thermal energy transports and recombination processes in carrier dynamics study.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140811837","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}

引用次数: 0

Well Number Dependence of Internal Quantum Efficiency in AlGaN Quantum Wells on Low‐Dislocation Sputtered AlN Templates 低位错溅射氮化铝模板上氮化铝量子阱内部量子效率的阱数依赖性

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-27 DOI: 10.1002/pssb.202300567

Kosuke Inai, Ryota Oshimura, Kunio Himeno, Megumi Fujii, Yuta Onishi, Satoshi Kurai, Narihito Okada, Kenjiro Uesugi, Hideto Miyake, Yoichi Yamada

引用次数: 0

Accelerating Nonequilibrium Green Functions Simulations: The G1–G2 Scheme and Beyond 加速非平衡格林函数模拟：G1-G2 方案及其他

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-26 DOI: 10.1002/pssb.202300578

Michael Bonitz, Jan‐Philip Joost, Christopher Makait, Erik Schroedter, Tim Kalsberger, Karsten Balzer

{"title":"Accelerating Nonequilibrium Green Functions Simulations: The G1–G2 Scheme and Beyond","authors":"Michael Bonitz, Jan‐Philip Joost, Christopher Makait, Erik Schroedter, Tim Kalsberger, Karsten Balzer","doi":"10.1002/pssb.202300578","DOIUrl":"https://doi.org/10.1002/pssb.202300578","url":null,"abstract":"The theory of nonequilibrium Green functions (NEGF) has seen a rapid development over the recent three decades. Applications include diverse correlated many‐body systems in and out of equilibrium. Very good agreement with experiments and available exact theoretical results could be demonstrated if the proper selfenergy approximations were used. However, full two‐time NEGF simulations are computationally costly, as they suffer from a cubic scaling of the computation time with the simulation duration. Recently the G1–G2 scheme that exactly reformulates the generalized Kadanoff–Baym ansatz with Hartree–Fock propagators (HF‐GKBA) into time‐local equations is introduced, which achieves time‐linear scaling and allows for a dramatic speedup and extension of the simulations (Schluenzen et al. Phys. Rev. Lett. 2020, 124, 076601). Remarkably, this scaling is achieved quickly, and also for high‐level selfenergies, including the nonequilibrium GW and T‐matrix approximations (Joost et al. Phys. Rev. B 2020, 101, 245101). Even the dynamically screened ladder approximation is now feasible (Joost et al. Phys. Rev. B 2022, 105, 165155), and also applications to electron‐boson systems are demonstrated. Herein, an overview on recent results that are achieved with the G1–G2 scheme is presented. Problems and open questions are discussed and further ideas of how to overcome the current limitations of the scheme and present are presented. The G1–G2 scheme is illustrated by presenting applying it to the excitation dynamics of Hubbard clusters, to optical excitation of graphene, and to charge transfer during stopping of ions by correlated materials.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140806167","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}

引用次数: 0

Red Emission of Well‐Ordered InGaN/GaN Nanocolumn Arrays on Si (111) Substrates Grown via Nanotemplate Selective‐Area Growth 通过纳米模板选择性面积生长技术在 Si (111) 基质上生长的井然有序的 InGaN/GaN 纳米柱阵列的红色发射率

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-26 DOI: 10.1002/pssb.202400064

Kota Hoshino, Rie Togashi, Katsumi Kishino

{"title":"Red Emission of Well‐Ordered InGaN/GaN Nanocolumn Arrays on Si (111) Substrates Grown via Nanotemplate Selective‐Area Growth","authors":"Kota Hoshino, Rie Togashi, Katsumi Kishino","doi":"10.1002/pssb.202400064","DOIUrl":"https://doi.org/10.1002/pssb.202400064","url":null,"abstract":"Herein, triangular‐lattice nanopillar templates are fabricated on sputter‐deposited AlN/Si (111) substrates. Nanotemplate selective‐area growth via radiofrequency‐plasma‐assisted molecular beam epitaxy is employed to grow GaN nanocolumns on the nanopillars. Well‐ordered uniform GaN nanocolumn arrays are obtained by inserting a migration‐enhanced‐epitaxy grown AlN/AlGaN buffer layer, thereby aligning the polarity of GaN to Ga‐polar. Subsequently, bulk InGaN active layers are grown on top of the GaN nanocolumns with increasing growth time (tg = 10–20 min). In the initial stage of growth (tg = 10 min), low‐In‐content InGaN grows on the edges of the six‐sided pyramidal top of the GaN nanocolumns. As the growth progresses, low‐In‐composition InGaN fills the sides between InGaN on the edges, while high‐In‐composition InGaN rapidly grows on the top of the c‐plane nanocolumns. High‐angle annular dark‐field scanning transmission electron microscopy reveals the formation of an InGaN core, covered with a low‐In‐composition InGaN shell, on the top of the nanocolumns. At tg = 20 min, the photoluminescence spectrum exhibits a peak at 669 nm with a full width at half maximum value of 51.7 nm. Thus, the proposed method is suitable for growing red‐light‐emitting well‐ordered InGaN/GaN nanocolumn arrays on Si.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140800271","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}

引用次数: 0

Improvement of Photoconductivity in a‐Oriented α‐Ga2O3 Thin Films Grown on Sapphire Substrates by Mist Chemical Vapor Deposition 利用喷雾化学气相沉积法提高蓝宝石基底上生长的面向 a 的 α-Ga2O3 薄膜的光导率

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-26 DOI: 10.1002/pssb.202300463

Kazuyuki Uno, Keishi Yamaoka

{"title":"Improvement of Photoconductivity in a‐Oriented α‐Ga2O3 Thin Films Grown on Sapphire Substrates by Mist Chemical Vapor Deposition","authors":"Kazuyuki Uno, Keishi Yamaoka","doi":"10.1002/pssb.202300463","DOIUrl":"https://doi.org/10.1002/pssb.202300463","url":null,"abstract":"α‐Ga2O3 is a suitable material for UV‐C optical devices owing to its optical absorption edge wavelength. In this study, α‐Ga2O3 thin films are grown on c‐, a‐, m‐, n‐, and r‐oriented sapphire substrates by mist chemical vapor deposition. Furthermore, their structural fluctuations, (normal direction of the surface) and (rotational direction on the surface), are examined. As a result, the a‐oriented α‐Ga2O3 thin films exhibit the smallest and . Based on the results of the previous examination, metal–semiconductor–metal (MSM) photodetectors are fabricated using c‐ and a‐oriented α‐Ga2O3 thin films and their photoconducting properties are characterized. Under D2 lamp light illumination, the MSM photodetector using a‐oriented films produces photocurrent four to six times greater than those using c‐oriented films. The visible‐light rejection ratios are at 10 V and 105.2 at 24 V. The photoresponsivity is estimated to be 2.2 A W−1 under the illumination of a D2 UV lamp and 24 V bias voltage. In these results, it is suggested that the a‐oriented α‐Ga2O3 thin film exhibits a higher in‐plane carrier mobility than the c‐oriented film. Thus, a‐oriented α‐Ga2O3 films are more suitable than c‐oriented α‐Ga2O3 films for fabricating MSM photodetectors.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140800270","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}

引用次数: 0

Correlative Micro‐Photoluminescence Study on Hybrid Quantum‐Well InGaN Red Light‐Emitting Diodes 混合量子阱 InGaN 红色发光二极管的相关微光研究

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-26 DOI: 10.1002/pssb.202400036

Zhaozong Zhang, Ryota Ishii, Kanako Shojiki, Mitsuru Funato, Daisuke Iida, Kazuhiro Ohkawa, Yoichi Kawakami

{"title":"Correlative Micro‐Photoluminescence Study on Hybrid Quantum‐Well InGaN Red Light‐Emitting Diodes","authors":"Zhaozong Zhang, Ryota Ishii, Kanako Shojiki, Mitsuru Funato, Daisuke Iida, Kazuhiro Ohkawa, Yoichi Kawakami","doi":"10.1002/pssb.202400036","DOIUrl":"https://doi.org/10.1002/pssb.202400036","url":null,"abstract":"To investigate nonradiative recombination processes in indium gallium nitride (InGaN)‐based red light‐emitting diodes (LEDs), an InGaN‐based red LED with a hybrid quantum well (QW) structure consisting of red and blue single quantum wells (SQWs) is characterized by micro‐photoluminescence (μ‐PL) spectroscopy. The μ‐PL mapping of the red emission reveals numerous dark spots with various sizes and contrasts. Not only the red and blue (from a blue SQW) but green emission bands are observed at some red dark spots, suggesting that indium (In) segregation is one of the causes of nonradiative recombination in the red emission. Comparing the blue and green emission images to the red emission image reveals that the dark spots in the intensity map of the red emission can be classified into four types. Through this correlative analysis, the red dark spots associated with the dark areas in the intensity map of the blue emission are attributed to the major nonradiative recombination centers in the red emission.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140800269","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}

引用次数: 0

Metal–Organic Chemical Vapor Deposition of n‐AlGaN Grown on Strain‐Relaxed Distributed Bragg Reflector Buffer Layers 在应变松弛分布式布拉格反射器缓冲层上生长氮化铝镓的金属有机化学气相沉积技术

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-22 DOI: 10.1002/pssb.202300558

Hisashi Yamada, Naoto Kumagai, Toshikazu Yamada

{"title":"Metal–Organic Chemical Vapor Deposition of n‐AlGaN Grown on Strain‐Relaxed Distributed Bragg Reflector Buffer Layers","authors":"Hisashi Yamada, Naoto Kumagai, Toshikazu Yamada","doi":"10.1002/pssb.202300558","DOIUrl":"https://doi.org/10.1002/pssb.202300558","url":null,"abstract":"The strain relaxation, surface morphology, and reflectivity of AlGaN‐distributed Bragg reflectors (DBRs) grown via metal–organic chemical vapor deposition on AlN/Al2O3 templates are investigated. Strain relaxation begins in a 10‐period Al0.50Ga0.50N (27 nm)/Al0.75Ga0.25N (29 nm) DBR, and the degree of strain relaxation (DSR) increases with the number of DBR periods. The 30‐period DBR exhibits a peak reflectivity of 0.82 at 279 nm, with a stopband of 12 nm. The DSR of n‐Al0.62Ga0.38N on the 30‐period DBR increases from 70% to 100% as the n‐Al0.62Ga0.38N thickness increases from 0.4 to 2.5 μm. Although the surface of a DBR comprises numerous spiral hillocks, n‐Al0.62Ga0.38N grown on an AlGaN DBR exhibits a step‐flow growth. A DSR of 100% with threading screw dislocations of 2.0 × 108 cm−2 and threading edge dislocations of 1.2 × 109 cm−2 is obtained for a 2.5 μm‐thick n‐Al0.62Ga0.38N on a 30‐period AlGaN DBR.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140635432","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}

引用次数: 0

The Nonradiative Properties of Self‐Trapped Holes in Ultra‐Wide Bandgap Gallium Oxide Film 超宽带隙氧化镓薄膜中自阱的非辐射特性

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-22 DOI: 10.1002/pssb.202300590

Isiaka Lukman, Leah Bergman

{"title":"The Nonradiative Properties of Self‐Trapped Holes in Ultra‐Wide Bandgap Gallium Oxide Film","authors":"Isiaka Lukman, Leah Bergman","doi":"10.1002/pssb.202300590","DOIUrl":"https://doi.org/10.1002/pssb.202300590","url":null,"abstract":"The photoluminescence (PL) of self‐trapped holes (STH) in ultra‐wide bandgap β‐Ga2O3 is commonly its most dominant light emission and is an inherent property. Thus, gaining knowledge of the crystal dynamics that impact the PL properties is vital to sensor and other technologies. The PL, Raman‐phonons, and their interactions are studied at an extreme temperature range of 77–622 K. The PL is studied up to the bandgap value of ≈5 eV. It is found that the high‐energy Raman modes provide a major route to the nonradiative process of the PL via STH–phonon interaction with an activation energy of 72 meV. This dynamic is modeled with the configurational coordinate scheme at the strong phonon coupling limit. The exceptionally broad Gaussian PL linewidth manifests this coupling. The weak temperature response of the PL energy peak position indicates that the STH has characteristics of a deep‐level defect. This contrasts with the large redshift of ≈220 meV of the optical gap of the film, ascertained from transmission. Unlike the temperature response of the high‐energy phonons, the behavior of the low‐energy phonons is found to follow the Bose–Einstein population increase, indicating no strong interaction with the STH.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140635568","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}

引用次数: 0

Theoretical Study of Carbon K‐Edge Energy‐Loss Near‐Edge Structure Spectra in the Ordered Mo2TiAlC2 MAX and Mo2TiC2 MXene 有序 Mo2TiAlC2 MAX 和 Mo2TiC2 MXene 中碳 K 边缘能量损失近边缘结构光谱的理论研究

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-22 DOI: 10.1002/pssb.202400012

Zahra Derikvandi, Mehrdad Dadsetani

{"title":"Theoretical Study of Carbon K‐Edge Energy‐Loss Near‐Edge Structure Spectra in the Ordered Mo2TiAlC2 MAX and Mo2TiC2 MXene","authors":"Zahra Derikvandi, Mehrdad Dadsetani","doi":"10.1002/pssb.202400012","DOIUrl":"https://doi.org/10.1002/pssb.202400012","url":null,"abstract":"By means of density functional theory, the energy‐loss near‐edge structure (ELNES) of carbon K‐edge of Mo2TiAlC2 and corresponding MoTiC2 Mxene at orientational‐independent condition is dealt with. Compared to the MAX (M is transition metal, A is an elment from group 13–16, X is C or N) phase, the energy separations increase between the main spectral features at the C K edge of Mo2TiC2 MXene owing to the structural change and decreased bond length. The dispersions of the C K edge in both systems are similar to p‐symmetry densities of states. It is indicated that the source of the first fine structure at the C 1s edge in both phases mainly comes from the electron transfer to px + py‐like character. The other fine structures result from the transition to hybridization of pz and px + py states with the prominent contribution of px + py‐like character. Moreover, the comparison of C K‐edge ELNES spectra in three Mo‐based compounds reveals that, ongoing from Mo2TiAlC2 to Mo2TiC2 and then to Mo2C, the energy position of the fine structures is shifted to higher energies (blueshifted), due to the quantum confinement effects and the change of the chemical environment around the excited carbon.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140635738","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}

引用次数: 0

New Debye Temperature Model of 4H‐SiC Crystal 4H-SiC 晶体的新型德拜温度模型

IF 1.6 4区物理与天体物理

Physica Status Solidi B-basic Solid State Physics Pub Date : 2024-04-18 DOI: 10.1002/pssb.202400104

Wei Jun Hsiung, Chih Shan Tan

引用次数: 0