Herein, the structural, optical, and magnetic properties of Y0.85La0.15FexAlyO3: (x; y) where x = 1; y = 0, x = 0.975; y = 0.025, x = 0.95; y = 0.05, and x = 0.9; y = 0.1 nanomaterials obtained from sol–gel method are reported. The X‐ray powder diffraction (XRD) for the structural characterization, scanning electron microscopy for crystallite size estimation, ultraviolet–visible absorption for optical studies, and vibrating‐sample magnetometer for magnetic studies are used in this investigation. An increase of orthorhombic crystal structure with an increase of Al content in the sample is observed from XRD studies. The existence of all the elements present in the samples is observed from energy‐dispersive X‐ray spectroscopy. The optical bandgap increases from 2.04 to 2.10 eV with an increase of Al concentration from 0 to 0.05. The observed magnetization value is 3.14 emu g−1 for y = 0.05, which is higher than y = 0 (2.11 emu g−1) and y = 0.024 (2.58 emu g−1). In summary, the obtained result (x = 0.95; y = 0.05) can be useful for different magnetic‐based applications.
本文报告了溶胶-凝胶法获得的 Y0.85La0.15FexAlyO3: (x; y) （其中 x = 1; y = 0、x = 0.975; y = 0.025、x = 0.95; y = 0.05 和 x = 0.9; y = 0.1）纳米材料的结构、光学和磁学特性。本研究采用了 X 射线粉末衍射（XRD）进行结构表征，扫描电子显微镜进行晶粒尺寸估算，紫外可见吸收进行光学研究，振动样品磁力计进行磁性研究。从 XRD 研究中可以观察到，随着样品中铝含量的增加，正方晶体结构也在增加。从能量色散 X 射线光谱中可以观察到样品中所有元素的存在。随着铝浓度从 0 增加到 0.05，光带隙从 2.04 eV 增加到 2.10 eV。y = 0.05 时的磁化值为 3.14 emu g-1，高于 y = 0（2.11 emu g-1）和 y = 0.024（2.58 emu g-1）。总之，所得结果（x = 0.95; y = 0.05）可用于不同的磁性应用。
{"title":"Synergistic Influence of Doping and Co‐Doping of Trivalent Ions (La+3 and Al+3) on YFeO3 Nanomaterials","authors":"Sajini Kalakonda, Rama Sekhara Reddy Dachuru, Krishnaveni Gudela","doi":"10.1002/pssb.202400190","DOIUrl":"https://doi.org/10.1002/pssb.202400190","url":null,"abstract":"Herein, the structural, optical, and magnetic properties of Y<jats:sub>0.85</jats:sub>La<jats:sub>0.15</jats:sub>Fe<jats:sub><jats:italic>x</jats:italic></jats:sub>Al<jats:sub><jats:italic>y</jats:italic></jats:sub>O<jats:sub>3</jats:sub>: (<jats:italic>x</jats:italic>; <jats:italic>y</jats:italic>) where <jats:italic>x</jats:italic> = 1; <jats:italic>y</jats:italic> = 0, <jats:italic>x</jats:italic> = 0.975; <jats:italic>y</jats:italic> = 0.025, <jats:italic>x</jats:italic> = 0.95; <jats:italic>y</jats:italic> = 0.05, and <jats:italic>x</jats:italic> = 0.9; <jats:italic>y</jats:italic> = 0.1 nanomaterials obtained from sol–gel method are reported. The X‐ray powder diffraction (XRD) for the structural characterization, scanning electron microscopy for crystallite size estimation, ultraviolet–visible absorption for optical studies, and vibrating‐sample magnetometer for magnetic studies are used in this investigation. An increase of orthorhombic crystal structure with an increase of Al content in the sample is observed from XRD studies. The existence of all the elements present in the samples is observed from energy‐dispersive X‐ray spectroscopy. The optical bandgap increases from 2.04 to 2.10 eV with an increase of Al concentration from 0 to 0.05. The observed magnetization value is 3.14 emu g<jats:sup>−1</jats:sup> for <jats:italic>y</jats:italic> = 0.05, which is higher than <jats:italic>y</jats:italic> = 0 (2.11 emu g<jats:sup>−1</jats:sup>) and <jats:italic>y</jats:italic> = 0.024 (2.58 emu g<jats:sup>−1</jats:sup>). In summary, the obtained result (<jats:italic>x</jats:italic> = 0.95; <jats:italic>y</jats:italic> = 0.05) can be useful for different magnetic‐based applications.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"35 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141570461","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}
Herein, Monte Carlo simulation of gold droplets motion on Si(111) and Si(011) surfaces during the gold deposition is carried out. The influence of gold deposition rate F on the Au–Si droplet velocity on the silicon surfaces with (111) and (011) orientations is analyzed. On the vicinal (111) surface, the droplet moves with almost constant velocity, while, on the (011) surface, the droplet velocity decreases as the Au deposition rate increases. It is demonstrated that the droplet velocity dependence on the gold deposition rate is determined by the droplet size change. The etching anisotropy of substrates with different orientations leads to different shapes of an etch pit under the droplet on Si(111) and Si(011) surfaces. This results in differences in the droplet velocity depending on the gold deposition rate on (111) and (011) surfaces. The feature of the droplet motion on the Si(011) surface is demonstrated: the droplets are able to merge due to the possibility of motion in two opposite directions.
{"title":"Effect of Au Deposition Rate on the Gold Droplet Velocity on Si(111) and Si(011) Surfaces (Monte Carlo Simulation)","authors":"Snezhana Mantsurova, Nataliya Shwartz","doi":"10.1002/pssb.202400103","DOIUrl":"https://doi.org/10.1002/pssb.202400103","url":null,"abstract":"Herein, Monte Carlo simulation of gold droplets motion on Si(111) and Si(011) surfaces during the gold deposition is carried out. The influence of gold deposition rate <jats:italic>F</jats:italic> on the Au–Si droplet velocity on the silicon surfaces with (111) and (011) orientations is analyzed. On the vicinal (111) surface, the droplet moves with almost constant velocity, while, on the (011) surface, the droplet velocity decreases as the Au deposition rate increases. It is demonstrated that the droplet velocity dependence on the gold deposition rate is determined by the droplet size change. The etching anisotropy of substrates with different orientations leads to different shapes of an etch pit under the droplet on Si(111) and Si(011) surfaces. This results in differences in the droplet velocity depending on the gold deposition rate on (111) and (011) surfaces. The feature of the droplet motion on the Si(011) surface is demonstrated: the droplets are able to merge due to the possibility of motion in two opposite directions.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"60 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548148","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}
Natsuko Omiya, Hideo Aida, Hidetoshi Takeda, Motoki Kanda, Toshiro Doi
Subsurface damage (SSD) structures induced by mechanical polishing of gallium nitride (GaN) substrates are comprehensively investigated using atomic force microscopy, cathodoluminescence (CL) imaging, and cross‐sectional transmittance electron microscopy. The low removal rate of the CMP process is a barrier to high productivity of a GaN wafering process; therefore, reducing the chemical mechanical polishing (CMP) process time by reducing the depth of SSD induced by mechanical processing is an active research area. To better understand the SSD structures, the surface roughness, SSD depth, and SSD distributions induced by mechanical polishing are quantitatively evaluated in this study. The SSD structures induced by mechanical polishing can be quantitatively exhibited as the SSD distribution with the damage strength at the outermost surface and the damage propagation, which are obtained by CMP process time‐resolved CL imaging method. On the basis of the analysis results, a schematic model of the SSD structures for mechanically polished GaN substrates is proposed.
{"title":"Analysis of Subsurface Damage Structures of Gallium Nitride Substrates Induced by Mechanical Polishing with Diamond Abrasives","authors":"Natsuko Omiya, Hideo Aida, Hidetoshi Takeda, Motoki Kanda, Toshiro Doi","doi":"10.1002/pssb.202400031","DOIUrl":"https://doi.org/10.1002/pssb.202400031","url":null,"abstract":"Subsurface damage (SSD) structures induced by mechanical polishing of gallium nitride (GaN) substrates are comprehensively investigated using atomic force microscopy, cathodoluminescence (CL) imaging, and cross‐sectional transmittance electron microscopy. The low removal rate of the CMP process is a barrier to high productivity of a GaN wafering process; therefore, reducing the chemical mechanical polishing (CMP) process time by reducing the depth of SSD induced by mechanical processing is an active research area. To better understand the SSD structures, the surface roughness, SSD depth, and SSD distributions induced by mechanical polishing are quantitatively evaluated in this study. The SSD structures induced by mechanical polishing can be quantitatively exhibited as the SSD distribution with the damage strength at the outermost surface and the damage propagation, which are obtained by CMP process time‐resolved CL imaging method. On the basis of the analysis results, a schematic model of the SSD structures for mechanically polished GaN substrates is proposed.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"30 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548146","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 perovskites are desirable materials for photovoltaic and other renewable green energy technologies. Lead‐based perovskite solar cells (PSC) have recently gained considerable attention due to the abrupt rise in power conversion efficiency, but lead's well‐known toxicity prevents its large‐scale commercialization. One compelling option is Cs2TiBr6, which offers a nontoxic alternative. Herein, the electronic and optical characteristics of Cs2TiBr6 absorber material using density functional theory employing the WIEN2K tool are investigated. The energy band structure of Cs2TiBr6 shows an indirect bandgap of 2.2 eV. Additionally, optical properties are calculated, and the suitability of this material as an absorber for indoor and outdoor photovoltaic devices is investigated. The Cs2TiBr6 material has a peak absorption coefficient of 39.57 × 104 cm−1 and optical conductivity of 1.98 × 1015s−1, demonstrating its suitability as an absorber material. After that, a PSC is modeled using SCAPS‐1D by using the computed parameters. The performance of the modeled perovskite is enhanced by optimization of various parameters, resulting in the achievement of a high‐performance Cs2TiBr6‐based PSC, boasting a power conversion efficiency of 19.9% for air mass AM1.5 G spectra and power conversion efficiency of 16.76% for light emitting diode and 17.18% for incandescent light for indoor light conditions.
{"title":"Comprehensive Modeling of High‐Performance All‐Inorganic Cs2TiBr6‐Based Perovskite Solar Cells","authors":"Sujit Kumar, Jasil Thiyyakkandy, Ashish Kumar Yadav, Valippurath Vinturaj, Vivek Garg, Sudheendra Prabhu, Sushil Kumar Pandey","doi":"10.1002/pssb.202400247","DOIUrl":"https://doi.org/10.1002/pssb.202400247","url":null,"abstract":"The perovskites are desirable materials for photovoltaic and other renewable green energy technologies. Lead‐based perovskite solar cells (PSC) have recently gained considerable attention due to the abrupt rise in power conversion efficiency, but lead's well‐known toxicity prevents its large‐scale commercialization. One compelling option is Cs<jats:sub>2</jats:sub>TiBr<jats:sub>6</jats:sub>, which offers a nontoxic alternative. Herein, the electronic and optical characteristics of Cs<jats:sub>2</jats:sub>TiBr<jats:sub>6</jats:sub> absorber material using density functional theory employing the WIEN2K tool are investigated. The energy band structure of Cs<jats:sub>2</jats:sub>TiBr<jats:sub>6</jats:sub> shows an indirect bandgap of 2.2 eV. Additionally, optical properties are calculated, and the suitability of this material as an absorber for indoor and outdoor photovoltaic devices is investigated. The Cs<jats:sub>2</jats:sub>TiBr<jats:sub>6</jats:sub> material has a peak absorption coefficient of 39.57 × 10<jats:sup>4</jats:sup> cm<jats:sup>−1</jats:sup> and optical conductivity of 1.98 × 10<jats:sup>15</jats:sup>s<jats:sup>−1</jats:sup>, demonstrating its suitability as an absorber material. After that, a PSC is modeled using SCAPS‐1D by using the computed parameters. The performance of the modeled perovskite is enhanced by optimization of various parameters, resulting in the achievement of a high‐performance Cs<jats:sub>2</jats:sub>TiBr<jats:sub>6</jats:sub>‐based PSC, boasting a power conversion efficiency of 19.9% for air mass AM1.5 G spectra and power conversion efficiency of 16.76% for light emitting diode and 17.18% for incandescent light for indoor light conditions.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"30 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548147","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 presents a comprehensive analysis of the orthorhombic CsCuO, focusing on its structural, electronic, mechanical, and optical properties, which uses the first‐principles plane wave pseudopotential technique and local density approximation methods based on density functional theory. The derived structural parameters closely match the previously reported experimental data. The calculated results show that CsCuO is mechanically stable and exhibits a certain toughness. Research on electronic properties shows that CsCuO is a direct‐bandgap semiconductor. Charge density and population analysis show that covalent bonds are formed between O and Cu. The optical property results show that CsCuO has good passability to incident light, indicating that CsCuO is an excellent transparent material. In the visible and infrared light regions, CsCuO has a low absorption coefficient, mainly manifested as ultraviolet absorption. Reflection is mainly distributed in the high‐energy region and does not exceed 25% in the visible light region. It can be used in fields that require less light reflection and the manufacture of medical ultraviolet disinfection equipment.
{"title":"First‐Principles Studies of Structural, Mechanical, Electronic, and Optical Properties of CsCuO","authors":"Jing Liu, Qi‐Jun Liu, Zheng‐Tang Liu, Zhi‐Xin Bai","doi":"10.1002/pssb.202400125","DOIUrl":"https://doi.org/10.1002/pssb.202400125","url":null,"abstract":"This study presents a comprehensive analysis of the orthorhombic CsCuO, focusing on its structural, electronic, mechanical, and optical properties, which uses the first‐principles plane wave pseudopotential technique and local density approximation methods based on density functional theory. The derived structural parameters closely match the previously reported experimental data. The calculated results show that CsCuO is mechanically stable and exhibits a certain toughness. Research on electronic properties shows that CsCuO is a direct‐bandgap semiconductor. Charge density and population analysis show that covalent bonds are formed between O and Cu. The optical property results show that CsCuO has good passability to incident light, indicating that CsCuO is an excellent transparent material. In the visible and infrared light regions, CsCuO has a low absorption coefficient, mainly manifested as ultraviolet absorption. Reflection is mainly distributed in the high‐energy region and does not exceed 25% in the visible light region. It can be used in fields that require less light reflection and the manufacture of medical ultraviolet disinfection equipment.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"11 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141548145","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}
Daniel. A. Hunter, Gunasekar Naresh‐Kumar, Paul R. Edwards, Olha Makydonska, Fabien C. P. Massabuau, Isa Hatipoglu, Partha Mukhopadhyay, Winston V. Schoenfeld, Robert W. Martin
Electron beam techniques have been used to analyze the impact of substrate choice and growth parameters on the compositional and optical properties of tin gallium oxide [(SnxGa1−x)2O3] thin films grown by plasma‐assisted molecular beam epitaxy. Sn incorporation and film quality are found to be highly dependent on growth temperature and substrate material (silicon, sapphire, and bulk Ga2O3) with alloy concentrations varying up to an x value of 0.11. Room temperature cathodoluminescence spectra show the Sn alloying suppressing UV (3.3–3.0 eV), enhancing blue (2.8–2.4 eV), and generating green (2.4–2.0 eV) emission, indicative of the introduction of a high density of gallium vacancies (VGa) and subsequent VGa–Sn complexes. This behavior was further analyzed by mapping composition and luminescence across a cross section. Compared to Ga2O3, the spectral bands show a clear redshift due to bandgap reduction, confirmed by optical transmission measurements. The results show promise that the bandgap of gallium oxide can successfully be reduced through Sn alloying and used for bandgap engineering within UV optoelectronic devices.
{"title":"Tin Gallium Oxide Epilayers on Different Substrates: Optical and Compositional Analysis","authors":"Daniel. A. Hunter, Gunasekar Naresh‐Kumar, Paul R. Edwards, Olha Makydonska, Fabien C. P. Massabuau, Isa Hatipoglu, Partha Mukhopadhyay, Winston V. Schoenfeld, Robert W. Martin","doi":"10.1002/pssb.202400137","DOIUrl":"https://doi.org/10.1002/pssb.202400137","url":null,"abstract":"Electron beam techniques have been used to analyze the impact of substrate choice and growth parameters on the compositional and optical properties of tin gallium oxide [(Sn<jats:sub><jats:italic>x</jats:italic></jats:sub>Ga<jats:sub>1−<jats:italic>x</jats:italic></jats:sub>)<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>] thin films grown by plasma‐assisted molecular beam epitaxy. Sn incorporation and film quality are found to be highly dependent on growth temperature and substrate material (silicon, sapphire, and bulk Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>) with alloy concentrations varying up to an <jats:italic>x</jats:italic> value of 0.11. Room temperature cathodoluminescence spectra show the Sn alloying suppressing UV (3.3–3.0 eV), enhancing blue (2.8–2.4 eV), and generating green (2.4–2.0 eV) emission, indicative of the introduction of a high density of gallium vacancies (<jats:italic>V</jats:italic><jats:sub>Ga</jats:sub>) and subsequent <jats:italic>V</jats:italic><jats:sub>Ga</jats:sub>–Sn complexes. This behavior was further analyzed by mapping composition and luminescence across a cross section. Compared to Ga<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>, the spectral bands show a clear redshift due to bandgap reduction, confirmed by optical transmission measurements. The results show promise that the bandgap of gallium oxide can successfully be reduced through Sn alloying and used for bandgap engineering within UV optoelectronic devices.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"20 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527469","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}
Amine Harkati, Said Chouai, El‐Haddi Harkati, Abderrezak Bezazi, Salah Ellagoune, Fabrizio Scarpa
Stress concentrations pose a significant challenge in designing and optimizing composite components, often resulting in structural alterations and crack formation. This study delves into a detailed numerical and analytical analysis of stress concentration factors in composite materials, with a specific focus on the influence of negative Poisson's ratio and out‐of‐plane modulus. By exploring the interaction of these material properties, the objective is to devise effective strategies for alleviating stress concentrations in composite structures. Through analytical and numerical simulations, a robust correlation between the customized Poisson's ratio and modulus and the mitigation of stress concentration factors, particularly in epoxy/graphite‐reinforced composites are established. This tailored approach has the potential to enhance energy absorption capabilities and consequently reduce the risk of crack propagation in perforated laminated composite plates. This research findings offer valuable insights into composite material design, presenting innovative solutions for enhancing structural integrity and reducing susceptibility to stress‐related issues.
{"title":"Using a Negative Poisson's Ratio to Mitigate Stress Concentrations in Perforated Composite Plates","authors":"Amine Harkati, Said Chouai, El‐Haddi Harkati, Abderrezak Bezazi, Salah Ellagoune, Fabrizio Scarpa","doi":"10.1002/pssb.202400115","DOIUrl":"https://doi.org/10.1002/pssb.202400115","url":null,"abstract":"Stress concentrations pose a significant challenge in designing and optimizing composite components, often resulting in structural alterations and crack formation. This study delves into a detailed numerical and analytical analysis of stress concentration factors in composite materials, with a specific focus on the influence of negative Poisson's ratio and out‐of‐plane modulus. By exploring the interaction of these material properties, the objective is to devise effective strategies for alleviating stress concentrations in composite structures. Through analytical and numerical simulations, a robust correlation between the customized Poisson's ratio and modulus and the mitigation of stress concentration factors, particularly in epoxy/graphite‐reinforced composites are established. This tailored approach has the potential to enhance energy absorption capabilities and consequently reduce the risk of crack propagation in perforated laminated composite plates. This research findings offer valuable insights into composite material design, presenting innovative solutions for enhancing structural integrity and reducing susceptibility to stress‐related issues.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"144 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527228","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}
Mizuki Takahashi, Yuki Yamanaka, Shiori Ii, Ayaka Shima, Soma Inaba, Kosei Kubota, Yuta Hattori, Tetsuya Takeuchi, Motoaki Iwaya, Satoshi Kamiyama
For realizing room‐temperature continuous‐wave operation in core–shell GaN nanowire‐based semiconductor lasers, certain device characteristics are required, namely, a low threshold current and low operating voltage. To reduce the operating voltage and inject current into the m‐plane multiquantum shell (MQS) active region, a new structure with a tunnel junction and embedded n‐GaN is proposed. One of the problems in this proposed device architecture is the high resistance at the tunnel junction layer due to hydrogen passivation in the insufficiently activated p‐GaN shell. In situ activation annealing and suppression of re‐passivation during subsequent growth are necessary to reduce the operating voltage. Herein, the time and temperature dependence of in situ activation annealing in a reactor to lower the resistance of tunnel junction layers grown on nanowires with nonpolar m‐planes is investigated. Subsequent n+‐GaN growth is implemented at 550 °C. As a result, the turn‐on voltage is observed to be dependent on the activation annealing time and temperature. The lowest turn‐on voltage is ≈5.4 V at an activation annealing time of 30 min and activation annealing temperature of 800 °C.
{"title":"Optimization of In‐Reactor In Situ Activation Annealing Conditions for Tunnel Junction Layers in Multiquantum Shell GaN‐Based Devices","authors":"Mizuki Takahashi, Yuki Yamanaka, Shiori Ii, Ayaka Shima, Soma Inaba, Kosei Kubota, Yuta Hattori, Tetsuya Takeuchi, Motoaki Iwaya, Satoshi Kamiyama","doi":"10.1002/pssb.202400009","DOIUrl":"https://doi.org/10.1002/pssb.202400009","url":null,"abstract":"For realizing room‐temperature continuous‐wave operation in core–shell GaN nanowire‐based semiconductor lasers, certain device characteristics are required, namely, a low threshold current and low operating voltage. To reduce the operating voltage and inject current into the m‐plane multiquantum shell (MQS) active region, a new structure with a tunnel junction and embedded n‐GaN is proposed. One of the problems in this proposed device architecture is the high resistance at the tunnel junction layer due to hydrogen passivation in the insufficiently activated p‐GaN shell. In situ activation annealing and suppression of re‐passivation during subsequent growth are necessary to reduce the operating voltage. Herein, the time and temperature dependence of in situ activation annealing in a reactor to lower the resistance of tunnel junction layers grown on nanowires with nonpolar m‐planes is investigated. Subsequent n<jats:sup>+</jats:sup>‐GaN growth is implemented at 550 °C. As a result, the turn‐on voltage is observed to be dependent on the activation annealing time and temperature. The lowest turn‐on voltage is ≈5.4 V at an activation annealing time of 30 min and activation annealing temperature of 800 °C.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"213 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527468","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}
In the present research article, the structural, electronic, and optical characteristics of a novel perovskite halide, Mg3AsCl3, for a broad range of applications are thoroughly investigated. The characteristics of Mg3AsCl3 perovskite are investigated via the use of the generalized gradient approximation (GGA), Perdew–Burke–Ernzerhof and Heyd–Scuseria–Ernzerhof (HSE06) functionals, which are employed in conjunction with the linear combination of atomic orbital calculator. The structural, electrical, and optical characteristics of the material are investigated using density‐functional theory. In this study of the electronic characteristics, it is found that Mg3AsCl3 exhibits an indirect energy bandgap of 2.49 eV with GGA and 3.54 eV with HSE06. The complex band structure exhibits characteristics that indicate the presence of evanescent waves, which are characterized by a layer separation of 5 Å. The report in this research presents reflectivity values of 0.06328 and 0.02971 with GGA and HSE06 functionals, respectively. The reported values of the extinction coefficient are 3.36487 × 10−5 and 2.07389 × 10−5 calculated with GGA and HSE06 functionals. The value reported for the real dielectric function Re[ε] is 2.79625 with GGA and 2.00658 with HSE06. Overall, in these findings, an overview is given that Mg3AsCl3 holds potential as a candidate for use in a wide range of electronic device applications.
{"title":"Investigation of Structural, Electronic, and Optical Characteristics of a Novel Perovskite Halide, Mg3AsCl3, for Electronic Applications","authors":"Sonia Chahar, Krishna Kumar Mishra, Rajnish Sharma","doi":"10.1002/pssb.202400171","DOIUrl":"https://doi.org/10.1002/pssb.202400171","url":null,"abstract":"In the present research article, the structural, electronic, and optical characteristics of a novel perovskite halide, Mg<jats:sub>3</jats:sub>AsCl<jats:sub>3</jats:sub>, for a broad range of applications are thoroughly investigated. The characteristics of Mg<jats:sub>3</jats:sub>AsCl<jats:sub>3</jats:sub> perovskite are investigated via the use of the generalized gradient approximation (GGA), Perdew–Burke–Ernzerhof and Heyd–Scuseria–Ernzerhof (HSE06) functionals, which are employed in conjunction with the linear combination of atomic orbital calculator. The structural, electrical, and optical characteristics of the material are investigated using density‐functional theory. In this study of the electronic characteristics, it is found that Mg<jats:sub>3</jats:sub>AsCl<jats:sub>3</jats:sub> exhibits an indirect energy bandgap of 2.49 eV with GGA and 3.54 eV with HSE06. The complex band structure exhibits characteristics that indicate the presence of evanescent waves, which are characterized by a layer separation of 5 Å. The report in this research presents reflectivity values of 0.06328 and 0.02971 with GGA and HSE06 functionals, respectively. The reported values of the extinction coefficient are 3.36487 × 10<jats:sup>−5</jats:sup> and 2.07389 × 10<jats:sup>−5</jats:sup> calculated with GGA and HSE06 functionals. The value reported for the real dielectric function Re[<jats:italic>ε</jats:italic>] is 2.79625 with GGA and 2.00658 with HSE06. Overall, in these findings, an overview is given that Mg<jats:sub>3</jats:sub>AsCl<jats:sub>3</jats:sub> holds potential as a candidate for use in a wide range of electronic device applications.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"194 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508489","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}
In the present enquiry, an in‐depth analysis of internal energy, entropy, heat capacity, and Helmholtz free energy of GaAsquantum dot (QD) which contains Gaussian impurity as dopant and falls under the influence of applied Gaussian white noise (GWHN) is performed. GWHN takes additive and multiplicative routes for its entrance to the doped QD. In this study, highly delicate and complex interplay between temperature, presence/absence of GWHN, mode of incorporation of GWHN, and the particular physical parameters concerned is unveiled. The said interplay, in effect, designs the features of the thermal properties. The enquiry uncovers competitive behavior between thermal disorder and spatial disorder that also affects the said thermodynamic properties.
{"title":"Modulation of Thermodynamic Properties of Doped GaAs Quantum Dot under the Influence of Noise","authors":"Bhaskar Bhakti, Swarnab Datta, Manas Ghosh","doi":"10.1002/pssb.202300569","DOIUrl":"https://doi.org/10.1002/pssb.202300569","url":null,"abstract":"In the present enquiry, an in‐depth analysis of <jats:italic>internal energy</jats:italic>, <jats:italic>entropy</jats:italic>, <jats:italic>heat capacity</jats:italic>, and <jats:italic>Helmholtz free energy</jats:italic> of <jats:italic>GaAs</jats:italic> <jats:italic>quantum dot (QD)</jats:italic> which contains <jats:italic>Gaussian impurity</jats:italic> as dopant and falls under the influence of applied <jats:italic>Gaussian white noise (GWHN)</jats:italic> is performed. GWHN takes <jats:italic>additive</jats:italic> and <jats:italic>multiplicative</jats:italic> routes for its entrance to the doped QD. In this study, highly delicate and complex interplay between temperature, presence/absence of GWHN, mode of incorporation of GWHN, and the particular physical parameters concerned is unveiled. The said interplay, in effect, designs the features of the thermal properties. The enquiry uncovers competitive behavior between thermal disorder and spatial disorder that also affects the said thermodynamic properties.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"86 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141527475","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：