Chalcopyrite selenide single crystals and epitaxial layers (CuIn1−xGaxSe2, x = 0.00, 0.08, 0.19, 1.00) were characterized by temperature‐dependent photoreflectance (PR), photoluminescence (PL), photoluminescence–excitation (PLE), and variable excitation‐energy photoluminescence (VEPL) spectroscopy. The transition energies Ea, Eb, and Ec of both CuInSe2 (CIS) and CuGaSe2 (CGS) layers sensed by PR were higher than the energies of single crystals. CuInSe2 and CuGaSe2 grown on GaAs(001) underlie compressive and tensile stresses, respectively, which lead to band‐gap broadening in CIS and band‐gap narrowing in CGS. The increase of the Ea, Eb, Ec energies of tensely stressed CuGaSe2 layers to energies higher than those of the bulk originates from the stress dependence of the non‐cubic crystal field. Band‐gap scanning of the CuGaSe2 layer with continuous‐wave Ti:sapphire‐laser confirmed the absence of correlation between band‐gap readjustment and intrinsic defects. The energy of the band‐edge exciton EFE, in the PL‐spectra, was lower than the Ea transition energy, in the PR‐spectra, which is assigned to partial quenching of ΔCF with the increase of external tensile stress by gallium‐segregation at the chalcopyrite/GaAs‐interface. The stress dependence of ΔCF is negligible in CuInSe2 and linear, with a rate of 9 meV/100 MPa, in CuGaSe2. It is revealed that the energy band‐gap of photovoltaic chalcopyrite absorbers can be tuned by simultaneous built‐in and external lattice‐tuning.
{"title":"Dependence of Crystal‐Field Energy on Strain/Stress Sensed by Temperature Variation of Chalcopyrite Semiconductor (Optical) Band‐Gap for Efficient Band‐Gap Tuning in the CIS/CIGS Photovoltaic","authors":"Dimitra N. Papadimitriou","doi":"10.1002/pssb.202300552","DOIUrl":"https://doi.org/10.1002/pssb.202300552","url":null,"abstract":"Chalcopyrite selenide single crystals and epitaxial layers (CuIn<jats:sub>1−<jats:italic>x</jats:italic></jats:sub>Ga<jats:sub><jats:italic>x</jats:italic></jats:sub>Se<jats:sub>2</jats:sub>, <jats:italic>x</jats:italic> = 0.00, 0.08, 0.19, 1.00) were characterized by temperature‐dependent photoreflectance (PR), photoluminescence (PL), photoluminescence–excitation (PLE), and variable excitation‐energy photoluminescence (VEPL) spectroscopy. The transition energies <jats:italic>E</jats:italic><jats:sub>a</jats:sub>, <jats:italic>E</jats:italic><jats:sub>b</jats:sub>, and <jats:italic>E</jats:italic><jats:sub>c</jats:sub> of both CuInSe<jats:sub>2</jats:sub> (CIS) and CuGaSe<jats:sub>2</jats:sub> (CGS) layers sensed by PR were higher than the energies of single crystals. CuInSe<jats:sub>2</jats:sub> and CuGaSe<jats:sub>2</jats:sub> grown on GaAs(001) underlie compressive and tensile stresses, respectively, which lead to band‐gap broadening in CIS and band‐gap narrowing in CGS. The increase of the <jats:italic>E</jats:italic><jats:sub>a</jats:sub>, <jats:italic>E</jats:italic><jats:sub>b</jats:sub>, <jats:italic>E</jats:italic><jats:sub>c</jats:sub> energies of tensely stressed CuGaSe<jats:sub>2</jats:sub> layers to energies higher than those of the bulk originates from the stress dependence of the non‐cubic crystal field. Band‐gap scanning of the CuGaSe<jats:sub>2</jats:sub> layer with continuous‐wave Ti:sapphire‐laser confirmed the absence of correlation between band‐gap readjustment and intrinsic defects. The energy of the band‐edge exciton <jats:italic>E</jats:italic><jats:sub>FE</jats:sub>, in the PL‐spectra, was lower than the <jats:italic>E</jats:italic><jats:sub>a</jats:sub> transition energy, in the PR‐spectra, which is assigned to partial quenching of Δ<jats:sub>CF</jats:sub> with the increase of external tensile stress by gallium‐segregation at the chalcopyrite/GaAs‐interface. The stress dependence of Δ<jats:sub>CF</jats:sub> is negligible in CuInSe<jats:sub>2</jats:sub> and linear, with a rate of 9 meV/100 MPa, in CuGaSe<jats:sub>2</jats:sub>. It is revealed that the energy band‐gap of photovoltaic chalcopyrite absorbers can be tuned by simultaneous built‐in and external lattice‐tuning.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"3 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141948989","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 recent year has witnessed a flurry of activities in investigating the promising electronic, optical, and transport properties of lead‐free double perovskite halides. In the present work, the structural, electronic, optical, and transport properties of Cs2(Li/Na)GaI6 are carefully examined. The predicted negative formation energy, absence of imaginary frequency in the phonon spectra, and ab‐initio molecular dynamics calculations show that they are thermodynamically stable. Additionally, electronic studies employing generalized gradient approximation (GGA)–Perdew–Burke–Ernzerhof (PBE) + modified Becke‐Johnson + spin‐orbit coupling reveal that Cs2(Li/Na)GaI6 exhibits a direct bandgap, with values of 1.24 eV for Cs2LiGaI6 and 1.39 eV for Cs2NaGaI6. The exceptional optical properties, including a high absorption coefficient (105 cm−1) and excellent optical conductivity with low reflectivity across the entire UV–visible range, indicate that Cs2(Li/Na)GaI6 are promising materials for solar cell applications. Moreover, the ultralow thermal conductivity, high Seebeck coefficient, and substantial electrical conductivity of Cs2(Li/Na)GaI6 result in a high figure of merit over the temperature range of 200–600 K. Thus, Cs2(Li/Na)GaI6 shows strong potential as both photovoltaic and thermoelectric materials.
{"title":"Ab Initio Study of Structural, Electronic, Optical, and Thermoelectric Properties of Cs2(Li/Na)GaI6 for Green Energy Applications","authors":"Mukaddar Sk, Gourav Gourav, Saurabh Ghosh","doi":"10.1002/pssb.202400263","DOIUrl":"https://doi.org/10.1002/pssb.202400263","url":null,"abstract":"The recent year has witnessed a flurry of activities in investigating the promising electronic, optical, and transport properties of lead‐free double perovskite halides. In the present work, the structural, electronic, optical, and transport properties of Cs<jats:sub>2</jats:sub>(Li/Na)GaI<jats:sub>6</jats:sub> are carefully examined. The predicted negative formation energy, absence of imaginary frequency in the phonon spectra, and ab‐initio molecular dynamics calculations show that they are thermodynamically stable. Additionally, electronic studies employing generalized gradient approximation (GGA)–Perdew–Burke–Ernzerhof (PBE) + modified Becke‐Johnson + spin‐orbit coupling reveal that Cs<jats:sub>2</jats:sub>(Li/Na)GaI<jats:sub>6</jats:sub> exhibits a direct bandgap, with values of 1.24 eV for Cs<jats:sub>2</jats:sub>LiGaI<jats:sub>6</jats:sub> and 1.39 eV for Cs<jats:sub>2</jats:sub>NaGaI<jats:sub>6</jats:sub>. The exceptional optical properties, including a high absorption coefficient (10<jats:sup>5</jats:sup> cm<jats:sup>−1</jats:sup>) and excellent optical conductivity with low reflectivity across the entire UV–visible range, indicate that Cs<jats:sub>2</jats:sub>(Li/Na)GaI<jats:sub>6</jats:sub> are promising materials for solar cell applications. Moreover, the ultralow thermal conductivity, high Seebeck coefficient, and substantial electrical conductivity of Cs<jats:sub>2</jats:sub>(Li/Na)GaI<jats:sub>6</jats:sub> result in a high figure of merit over the temperature range of 200–600 K. Thus, Cs<jats:sub>2</jats:sub>(Li/Na)GaI<jats:sub>6</jats:sub> shows strong potential as both photovoltaic and thermoelectric materials.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"4 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141948904","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}
Raul Fernando Cuevas, Silvio Jose Prado, Victor Ciro Solano Reynoso, Lauro Antonio Pradela Filho, Pablo Henrique Menezes, Miguel Angel Gonzalez Balanta
Herein, CdTe/MnS core/shell nanoparticles dispersed in an aqueous solution have been synthesized. The formation of MnS semiconductor shell occurs by spontaneous self‐assembly. This process is activated by thermal hydrolysis that removes the excess of thiol and releases S2− ions. In this process, Mn2+ ions on the surface of the CdTe nanoparticles bind to S2− ions to produce a fine semiconducting layer of MnS. Measurements of Raman spectroscopy, optical absorption, and electrochemical measurements are performed. The Raman spectrum shows CdTe characteristic bands at 141 and 163 cm−1. Bands at 221 and 444 cm−1 are associated with the MnS structure. Cyclic voltammetry and differential pulse voltammetry are used to estimate the electrochemical gap at ≈2.47 eV. Absorption optical measurements show tree absorption bands. A broad band between 460 and 520 nm is associated with the first transition in CdTe nanoparticle. The absorption spectrum reveals an optical gap in the range of 2.41–2.33 eV for all the refluxed samples. These values are consistent with those obtained with the electrochemical measurements. The results evidence the formation of a core–shell semiconducting nanostructure made of CdTe nanoparticles coated with a spontaneously self‐assembled thin layer of MnS nanoparticles.
{"title":"Self‐Assembly of MnS Shell on CdTe Nanoparticles Induced by Thermohydrolysis: Synthesis and Characterization","authors":"Raul Fernando Cuevas, Silvio Jose Prado, Victor Ciro Solano Reynoso, Lauro Antonio Pradela Filho, Pablo Henrique Menezes, Miguel Angel Gonzalez Balanta","doi":"10.1002/pssb.202400248","DOIUrl":"https://doi.org/10.1002/pssb.202400248","url":null,"abstract":"Herein, CdTe/MnS core/shell nanoparticles dispersed in an aqueous solution have been synthesized. The formation of MnS semiconductor shell occurs by spontaneous self‐assembly. This process is activated by thermal hydrolysis that removes the excess of thiol and releases S<jats:sup>2−</jats:sup> ions. In this process, Mn<jats:sup>2+</jats:sup> ions on the surface of the CdTe nanoparticles bind to S<jats:sup>2−</jats:sup> ions to produce a fine semiconducting layer of MnS. Measurements of Raman spectroscopy, optical absorption, and electrochemical measurements are performed. The Raman spectrum shows CdTe characteristic bands at 141 and 163 cm<jats:sup>−1</jats:sup>. Bands at 221 and 444 cm<jats:sup>−1</jats:sup> are associated with the MnS structure. Cyclic voltammetry and differential pulse voltammetry are used to estimate the electrochemical gap at ≈2.47 eV. Absorption optical measurements show tree absorption bands. A broad band between 460 and 520 nm is associated with the first transition in CdTe nanoparticle. The absorption spectrum reveals an optical gap in the range of 2.41–2.33 eV for all the refluxed samples. These values are consistent with those obtained with the electrochemical measurements. The results evidence the formation of a core–shell semiconducting nanostructure made of CdTe nanoparticles coated with a spontaneously self‐assembled thin layer of MnS nanoparticles.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"15 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141948880","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}
Ejaz Ahmad Khera, Abrar Nazir, Zubair Ahmed, Mumtaz Manzoor, Hamid Ullah, Sabah Ansar, Yedluri Anil Kumar, Ramesh Sharma
Perovskite halides, owing to their environmental stability, non‐toxicity, and remarkable efficiency, are emerging as potential candidates for photovoltaic, solar cell, and thermodynamic applications. The electronic, optical, thermoelectric, and thermodynamic properties of cubic perovskite RbTmCl3 are studied using density functional theory (DFT). The electronic, optical, and thermoelectric properties are calculated both with and without spin‐orbit coupling (SOC) using the Tran and Blaha functional in the structure of the modified Becke Johnson (mBJ) exchange potential, while structural and mechanical properties are assessed using the exchange‐correlation functional calculated using the Perdew Burke Ernzerhof Generalized Gradient Approximation (PBE‐GGA). The negative formation energy (−592.39 KJ mol−1) and tolerance factor (1.17) for structural stability and current their existences in the cubic phase are found. Evaluation of the obtained data with and without SOC shows that the SOC effect causes the Tm‐d states to be shifted toward the level of Fermi, thereby decreasing the energy band gaps from 1.42 to 1.32 eV. Nevertheless, only the shift of the third variable peak to lower energies indicates the impact of SOC on optical properties. The effectiveness of RbTmCl3 in optical devices operating in the visible and ultraviolet regions is demonstrated by the exceptional absorption of light in these ranges. Using TB‐mBJ + SOC functional, the electronic band structure research reveals a direct semiconducting band gap of 1.32 eV in comparison to earlier calculations like LDA, PBE‐GGA, and TB‐mBJ. The absorption spectrum, reflectivity, extinction coefficient, refractive index, and dielectric function are displayed in addition to the electrical properties. Additionally, the quasi‐harmonic Debye model, which accounts for lattice vibrations, was used to study the corresponding volume, heat capacity, expansion of the heat coefficient, and Debye temperature of the RbTmCl3 crystal. We have calculated the thermoelectric parameters such as the Seebeck coefficient, thermal conductivity, electrical conductivity, and power factor as a function of temperature (100–900 K).
{"title":"Computational Prediction of Structural, Optoelectronic, Thermodynamic, and Thermoelectric Response of the Cubic Perovskite RbTmCl3 via DFT‐mBJ + SOC Studies","authors":"Ejaz Ahmad Khera, Abrar Nazir, Zubair Ahmed, Mumtaz Manzoor, Hamid Ullah, Sabah Ansar, Yedluri Anil Kumar, Ramesh Sharma","doi":"10.1002/pssb.202400123","DOIUrl":"https://doi.org/10.1002/pssb.202400123","url":null,"abstract":"Perovskite halides, owing to their environmental stability, non‐toxicity, and remarkable efficiency, are emerging as potential candidates for photovoltaic, solar cell, and thermodynamic applications. The electronic, optical, thermoelectric, and thermodynamic properties of cubic perovskite RbTmCl<jats:sub>3</jats:sub> are studied using density functional theory (DFT). The electronic, optical, and thermoelectric properties are calculated both with and without spin‐orbit coupling (SOC) using the Tran and Blaha functional in the structure of the modified Becke Johnson (mBJ) exchange potential, while structural and mechanical properties are assessed using the exchange‐correlation functional calculated using the Perdew Burke Ernzerhof Generalized Gradient Approximation (PBE‐GGA). The negative formation energy (−592.39 KJ mol<jats:sup>−1</jats:sup>) and tolerance factor (1.17) for structural stability and current their existences in the cubic phase are found. Evaluation of the obtained data with and without SOC shows that the SOC effect causes the Tm‐d states to be shifted toward the level of Fermi, thereby decreasing the energy band gaps from 1.42 to 1.32 eV. Nevertheless, only the shift of the third variable peak to lower energies indicates the impact of SOC on optical properties. The effectiveness of RbTmCl<jats:sub>3</jats:sub> in optical devices operating in the visible and ultraviolet regions is demonstrated by the exceptional absorption of light in these ranges. Using TB‐mBJ + SOC functional, the electronic band structure research reveals a direct semiconducting band gap of 1.32 eV in comparison to earlier calculations like LDA, PBE‐GGA, and TB‐mBJ. The absorption spectrum, reflectivity, extinction coefficient, refractive index, and dielectric function are displayed in addition to the electrical properties. Additionally, the quasi‐harmonic Debye model, which accounts for lattice vibrations, was used to study the corresponding volume, heat capacity, expansion of the heat coefficient, and Debye temperature of the RbTmCl<jats:sub>3</jats:sub> crystal. We have calculated the thermoelectric parameters such as the Seebeck coefficient, thermal conductivity, electrical conductivity, and power factor as a function of temperature (100–900 K).","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"21 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141887141","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}
Bhavik Thacker, Mitesh B. Solanki, Ratnamala Kharatmol, Yogesh D. Kale, Trilok Akhani
Utilizing density functional theory, the structural, electronic, vibrational, and thermophysical properties of L10 FePt, L12 Fe3Pt, and L12 FePt3 alloys are meticulously analyzed. Employing projected augmented wave pseudopotentials alongside the Perdew–Burke–Ernzerhof exchange‐correlation function, equilibrium lattice constants are computed, aligning closely with existing data, thus validating our approach. To ascertain the dynamical stability of these alloys, phonon frequencies and density of states across high symmetry directions of the Brillouin zone are computed, affirming their stability with positive phonon frequencies throughout. Furthermore, the electronic band structure, the total and projected density of states, electronic charge density, and Fermi surfaces of the alloys are delved. The thorough analysis of phonon dispersion curves, electronic band structures, and the density of states, charge densities, and Fermi surfaces provides conclusive insights into the properties and behavior of the alloys. In essence, comprehensive investigation offers valuable insights into the thermophysical properties of L10 FePt, L12 Fe3Pt, and L12 FePt3 alloys, spanning equilibrium lattice constants, phonon characteristics, and electronic properties. These findings significantly augment the understanding of the structural stability, phonon dynamics, and electronic behavior exhibited by these alloys.
{"title":"Exploring Structural, Electronic, Vibrational, and Thermophysical Properties of Fe–Pt, Fe3–Pt, and Fe–Pt3 Alloys: A Density Functional Theory Study","authors":"Bhavik Thacker, Mitesh B. Solanki, Ratnamala Kharatmol, Yogesh D. Kale, Trilok Akhani","doi":"10.1002/pssb.202400160","DOIUrl":"https://doi.org/10.1002/pssb.202400160","url":null,"abstract":"Utilizing density functional theory, the structural, electronic, vibrational, and thermophysical properties of L1<jats:sub>0</jats:sub> FePt, L1<jats:sub>2</jats:sub> Fe<jats:sub>3</jats:sub>Pt, and L1<jats:sub>2</jats:sub> FePt<jats:sub>3</jats:sub> alloys are meticulously analyzed. Employing projected augmented wave pseudopotentials alongside the Perdew–Burke–Ernzerhof exchange‐correlation function, equilibrium lattice constants are computed, aligning closely with existing data, thus validating our approach. To ascertain the dynamical stability of these alloys, phonon frequencies and density of states across high symmetry directions of the Brillouin zone are computed, affirming their stability with positive phonon frequencies throughout. Furthermore, the electronic band structure, the total and projected density of states, electronic charge density, and Fermi surfaces of the alloys are delved. The thorough analysis of phonon dispersion curves, electronic band structures, and the density of states, charge densities, and Fermi surfaces provides conclusive insights into the properties and behavior of the alloys. In essence, comprehensive investigation offers valuable insights into the thermophysical properties of L1<jats:sub>0</jats:sub> FePt, L1<jats:sub>2</jats:sub> Fe<jats:sub>3</jats:sub>Pt, and L1<jats:sub>2</jats:sub> FePt<jats:sub>3</jats:sub> alloys, spanning equilibrium lattice constants, phonon characteristics, and electronic properties. These findings significantly augment the understanding of the structural stability, phonon dynamics, and electronic behavior exhibited by these alloys.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"359 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866469","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}
Zhongyan Ouyang, Xiaodong Xu, Chengrui Che, Gewei Zhang, Tao Ying, Weiqi Li, Jianqun Yang, Xingji Li
Defect identification for unintentionally induced defects and radiation‐implemented defects always attracts great attention in semiconductor materials. Recent advances in carbon‐implemented single‐photon emitters in silicon urgently require the accurate identification of defect structures to reveal transition mechanisms. Using hybrid functional with finite size correction, we investigate the charge and optical transitions of carbon‐related defects, including CSiCSi, VSiCSi, CSi, SiiCSiCSi, and Ci. Except for Ci, other defects present the negative‐U feature in the charge transition process. CSiCSi and VSiCSi tend to perform p‐type conductivity with the electron capture transition close to the valence band, of which transition level ε (0/−1) is 0.30 eV for CSiCSi and ε (+1/−2) is 0.34 eV for VSiCSi. CSi and SiiCSiCSi present a bipolar doping character, and CSi tends to capture holes with transition ε (0/+2) = 0.10 eV. The optical transitions that typically emit or absorb light in the telecom optical wavelength bands are identified in these defects in terms of band edge recombination. The zero‐phonon lines of optical transitions of ε (+2/+1) for VSiCSi and Ci are consistent with a previous experiment involving single‐photon emitters. The findings are helpful to understand the performance degradation of silicon devices and provide a reference for identifying the structure of carbon‐related defects in silicon.
在半导体材料领域，无意诱导缺陷和辐射诱导缺陷的识别一直备受关注。最近在硅碳单光子发射器方面取得的进展迫切需要准确识别缺陷结构以揭示其转变机制。利用有限尺寸校正的混合函数，我们研究了碳相关缺陷的电荷和光学转变，包括 CSiCSi、VSiCSi、CSi、SiiCSiCSi 和 Ci。除 Ci 外，其他缺陷在电荷转换过程中均呈现负 U 特性。CSiCSi 和 VSiCSi 倾向于 p 型导电，电子捕获转变接近价带，其中 CSiCSi 的转变电平ε（0/-1）为 0.30 eV，VSiCSi 的转变电平ε（+1/-2）为 0.34 eV。CSi 和 SiiCSiCSi 具有双极掺杂特性，CSi 倾向于俘获空穴，其转变ε (0/+2) = 0.10 eV。在这些缺陷中，通常在电信光学波段发射或吸收光的光学转变是通过带边重组来确定的。VSiCSi 和 Ci 的光学转变 ε (+2/+1) 的零光子线与之前涉及单光子发射器的实验一致。这些发现有助于理解硅器件的性能退化，并为确定硅中碳相关缺陷的结构提供了参考。
{"title":"First Principles Investigations on the Carbon‐Related Defects in Silicon","authors":"Zhongyan Ouyang, Xiaodong Xu, Chengrui Che, Gewei Zhang, Tao Ying, Weiqi Li, Jianqun Yang, Xingji Li","doi":"10.1002/pssb.202400254","DOIUrl":"https://doi.org/10.1002/pssb.202400254","url":null,"abstract":"Defect identification for unintentionally induced defects and radiation‐implemented defects always attracts great attention in semiconductor materials. Recent advances in carbon‐implemented single‐photon emitters in silicon urgently require the accurate identification of defect structures to reveal transition mechanisms. Using hybrid functional with finite size correction, we investigate the charge and optical transitions of carbon‐related defects, including C<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub>, V<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub>, C<jats:sub>Si</jats:sub>, Si<jats:sub>i</jats:sub>C<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub>, and C<jats:sub>i</jats:sub>. Except for C<jats:sub>i</jats:sub>, other defects present the negative‐U feature in the charge transition process. C<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub> and V<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub> tend to perform p‐type conductivity with the electron capture transition close to the valence band, of which transition level <jats:italic>ε</jats:italic> (0/−1) is 0.30 eV for C<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub> and <jats:italic>ε</jats:italic> (+1/−2) is 0.34 eV for V<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub>. C<jats:sub>Si</jats:sub> and Si<jats:sub>i</jats:sub>C<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub> present a bipolar doping character, and C<jats:sub>Si</jats:sub> tends to capture holes with transition <jats:italic>ε</jats:italic> (0/+2) = 0.10 eV. The optical transitions that typically emit or absorb light in the telecom optical wavelength bands are identified in these defects in terms of band edge recombination. The zero‐phonon lines of optical transitions of <jats:italic>ε</jats:italic> (+2/+1) for V<jats:sub>Si</jats:sub>C<jats:sub>Si</jats:sub> and C<jats:sub>i</jats:sub> are consistent with a previous experiment involving single‐photon emitters. The findings are helpful to understand the performance degradation of silicon devices and provide a reference for identifying the structure of carbon‐related defects in silicon.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"48 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866483","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, the 1D Solar Cell Capacitance Simulator software is used to perform numerical analysis of thin‐film solar cells with Cu2ZnSnS4, Cu2BaSnS4, Cu2FeSnS4, and Cu2MnSnS4 absorber layers. The main goal is to investigate the impact of parameters, such as absorber layer thickness, acceptor density, buffer layer, bandgap, and donor density, on the efficiency of these solar cells. The absorber layer investigation entails varying the thickness and the acceptor density to evaluate their influence on the efficiency of the solar cell. A new zinc oxide sulfide (Zn(O,S)) buffer layer is also introduced instead of the conventional cadmium sulfide (CdS) buffer layer. The Zn(O,S) bandgap and its donor density, which are investigated in terms of how they affect the efficiency of the solar cells, have been varied. The optimal values for the thickness of the absorber layer, acceptor density, and the bandgap of the buffer layer are calculated. Subsequently, the donor density is evaluated to find any potential defects that may affect the efficiency of the solar cell. These results confirm that Zn(O,S) can be utilized as a buffer layer. This study concludes that Cu2ZnSnS4, Cu2BaSnS4, and Cu2MnSnS4 absorber layers have superior efficiency in comparison with Cu2FeSnS4.
{"title":"Enhanced Efficiency of Thin‐Film Solar Cells via Cation‐Substituted Kesterite Absorber Layers and Nontoxic Buffers: A Numerical Study","authors":"Balaji Gururajan, Atheek Posha, Wei‐Sheng Liu, Bhavya Kondapavuluri, Tarikallu Thippesh Abhishek, Perumal Thathireddy, Venkatesh Narasihman","doi":"10.1002/pssb.202400238","DOIUrl":"https://doi.org/10.1002/pssb.202400238","url":null,"abstract":"Herein, the 1D Solar Cell Capacitance Simulator software is used to perform numerical analysis of thin‐film solar cells with Cu<jats:sub>2</jats:sub>ZnSnS<jats:sub>4</jats:sub>, Cu<jats:sub>2</jats:sub>BaSnS<jats:sub>4</jats:sub>, Cu<jats:sub>2</jats:sub>FeSnS<jats:sub>4</jats:sub>, and Cu<jats:sub>2</jats:sub>MnSnS<jats:sub>4</jats:sub> absorber layers. The main goal is to investigate the impact of parameters, such as absorber layer thickness, acceptor density, buffer layer, bandgap, and donor density, on the efficiency of these solar cells. The absorber layer investigation entails varying the thickness and the acceptor density to evaluate their influence on the efficiency of the solar cell. A new zinc oxide sulfide (Zn(O,S)) buffer layer is also introduced instead of the conventional cadmium sulfide (CdS) buffer layer. The Zn(O,S) bandgap and its donor density, which are investigated in terms of how they affect the efficiency of the solar cells, have been varied. The optimal values for the thickness of the absorber layer, acceptor density, and the bandgap of the buffer layer are calculated. Subsequently, the donor density is evaluated to find any potential defects that may affect the efficiency of the solar cell. These results confirm that Zn(O,S) can be utilized as a buffer layer. This study concludes that Cu<jats:sub>2</jats:sub>ZnSnS<jats:sub>4</jats:sub>, Cu<jats:sub>2</jats:sub>BaSnS<jats:sub>4</jats:sub>, and Cu<jats:sub>2</jats:sub>MnSnS<jats:sub>4</jats:sub> absorber layers have superior efficiency in comparison with Cu<jats:sub>2</jats:sub>FeSnS<jats:sub>4</jats:sub>.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"19 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866474","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}
Mechanical behavior and plastic deformation mechanism of a new type of Co30Fe16.67Ni36.67Ti16.67 high entropy alloys (HEAs) have been calculated by the molecular dynamics method. The results show that the polycrystalline Co30Fe16.67Ni36.67Ti16.67 HEA has remarkable tensile plasticity and anisotropy. When the crystallographic orientation of the grain is <001>, the plastic deformation mechanism is face‐centered cubic (FCC)→body‐centered cubic (BCC) transformation and deformation twins. Grain boundary and vacancy reduce the nucleation energy of FCC→BCC phase transition, making BCC phase nucleation easy and growing in a shear manner, eventually forming deformation twins in the BCC phase. When the crystallographic orientation of grain is <110> and <111>, the plastic deformation mechanism is stacking faults, FCC→hexagonal‐close‐packed (HCP) phase transformation, and deformation twins. The motion of Shockley dislocation leads to the stacking fault, intrinsic stacking fault leads to the FCC→HCP phase transition, extrinsic stratification fault leads to the twin deformation, and the grain refining occurs during the tension process. Temperature and strain rate also have strong effects on tensile strength and elastic modulus. These results will provide a theoretical basis for the development of the HEAs and expand their application.
{"title":"Atomic Simulation of Deformation Behavior of Polycrystalline Co30Fe16.67Ni36.67Ti16.67 High Entropy Alloy Under Uniaxial Loading","authors":"Ying Fu, Wei Li, Qi Wang, Yinnan Sun, Qing Gao, Xu Xu, Junqiang Ren, Xuefeng Lu","doi":"10.1002/pssb.202400128","DOIUrl":"https://doi.org/10.1002/pssb.202400128","url":null,"abstract":"Mechanical behavior and plastic deformation mechanism of a new type of Co<jats:sub>30</jats:sub>Fe<jats:sub>16.67</jats:sub>Ni<jats:sub>36.67</jats:sub>Ti<jats:sub>16.67</jats:sub> high entropy alloys (HEAs) have been calculated by the molecular dynamics method. The results show that the polycrystalline Co<jats:sub>30</jats:sub>Fe<jats:sub>16.67</jats:sub>Ni<jats:sub>36.67</jats:sub>Ti<jats:sub>16.67</jats:sub> HEA has remarkable tensile plasticity and anisotropy. When the crystallographic orientation of the grain is <001>, the plastic deformation mechanism is face‐centered cubic (FCC)→body‐centered cubic (BCC) transformation and deformation twins. Grain boundary and vacancy reduce the nucleation energy of FCC→BCC phase transition, making BCC phase nucleation easy and growing in a shear manner, eventually forming deformation twins in the BCC phase. When the crystallographic orientation of grain is <110> and <111>, the plastic deformation mechanism is stacking faults, FCC→hexagonal‐close‐packed (HCP) phase transformation, and deformation twins. The motion of Shockley dislocation leads to the stacking fault, intrinsic stacking fault leads to the FCC→HCP phase transition, extrinsic stratification fault leads to the twin deformation, and the grain refining occurs during the tension process. Temperature and strain rate also have strong effects on tensile strength and elastic modulus. These results will provide a theoretical basis for the development of the HEAs and expand their application.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"86 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866472","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}
Yuxiang Fan, Bin Li, Cong Zhu, Jie Cheng, Shengli Liu, Zhixiang Shi
Herein, a series of ternary hydride compounds crystallizing in the cubic structure as potential rare‐earth and alkaline‐earth superconductors are designed and investigated. First‐principles calculations are performed on these prospective superconductors across the pressure range of 50–200 GPa, revealing their electronic band structures, phonon dispersions, electron–phonon (e–) interactions, and superconducting properties. Several compounds are identified as dynamically stable, with ScYbH and LuYbH remaining stable at 70 GPa and at 100 GPa. Notably, Eliashberg theory and e– coupling calculations predict CaLuH to exhibit a remarkable of up to 294 K at 180 GPa. In these findings, ternary hydrides are unveiled as a promising class of high‐temperature superconductors and insights are provided for achieving superconductivity at lower or ambient pressures through material design and exploration.
{"title":"Superconductive Sodalite‐Like Clathrate Hydrides MXH12$left(text{MXH}right)_{12}$ with Critical Temperatures of near 300 K under Pressures","authors":"Yuxiang Fan, Bin Li, Cong Zhu, Jie Cheng, Shengli Liu, Zhixiang Shi","doi":"10.1002/pssb.202400240","DOIUrl":"https://doi.org/10.1002/pssb.202400240","url":null,"abstract":"Herein, a series of ternary hydride compounds crystallizing in the cubic structure as potential rare‐earth and alkaline‐earth superconductors are designed and investigated. First‐principles calculations are performed on these prospective superconductors across the pressure range of 50–200 GPa, revealing their electronic band structures, phonon dispersions, electron–phonon (<jats:italic>e</jats:italic>–) interactions, and superconducting properties. Several compounds are identified as dynamically stable, with ScYbH and LuYbH remaining stable at 70 GPa and at 100 GPa. Notably, Eliashberg theory and <jats:italic>e</jats:italic>– coupling calculations predict CaLuH to exhibit a remarkable of up to 294 K at 180 GPa. In these findings, ternary hydrides are unveiled as a promising class of high‐temperature superconductors and insights are provided for achieving superconductivity at lower or ambient pressures through material design and exploration.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"18 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141866473","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 mechanical, electronic structure, and optical properties of lithium‐based perovskite LiMgX3 (X = Cl, Br, I) are investigated for the first time at 0–20 GPa using density‐functional theory. The Born stability criteria reveal that the phase transition points of LiMgCl3, LiMgBr3, and LiMgI3 are 20.7, 20.9, and 23.4 GPa, respectively. At 0 GPa, studies on the electronic properties using the Heyd‐Scuseria‐Ernzerhof (HSE06) functional show that LiMgCl3 and LiMgBr3 are indirect bandgap insulators with values of 5.336 and 4.113 eV, whereas LiMgI3 is an indirect bandgap semiconductor with a value of 2.055 eV. In addition, the bandgap calculated using both the PBEsol and HSE06 functionals decreases with increasing pressure, and the bandgap trends with pressure are consistent. Both functionals are also used to study the optical properties of LiMgX3 compounds, which show that they have potential for use in vacuum ultraviolet and photovoltaic applications. The mechanical and optical characteristics of the materials are significantly enhanced under pressure.
{"title":"Comparative Study of the Mechanical, Electronic Structure, and Optical Properties of Cubic Lithium‐Based Perovskite LiMgX3 (X = Cl, Br, I) under Pressure Effects: First‐Principles Calculations","authors":"Wei Luo, Shiyi Song, Yaxin Du, Siying Hu","doi":"10.1002/pssb.202400223","DOIUrl":"https://doi.org/10.1002/pssb.202400223","url":null,"abstract":"The mechanical, electronic structure, and optical properties of lithium‐based perovskite LiMgX<jats:sub>3</jats:sub> (X = Cl, Br, I) are investigated for the first time at 0–20 GPa using density‐functional theory. The Born stability criteria reveal that the phase transition points of LiMgCl<jats:sub>3</jats:sub>, LiMgBr<jats:sub>3</jats:sub>, and LiMgI<jats:sub>3</jats:sub> are 20.7, 20.9, and 23.4 GPa, respectively. At 0 GPa, studies on the electronic properties using the Heyd‐Scuseria‐Ernzerhof (HSE06) functional show that LiMgCl<jats:sub>3</jats:sub> and LiMgBr<jats:sub>3</jats:sub> are indirect bandgap insulators with values of 5.336 and 4.113 eV, whereas LiMgI<jats:sub>3</jats:sub> is an indirect bandgap semiconductor with a value of 2.055 eV. In addition, the bandgap calculated using both the PBEsol and HSE06 functionals decreases with increasing pressure, and the bandgap trends with pressure are consistent. Both functionals are also used to study the optical properties of LiMgX<jats:sub>3</jats:sub> compounds, which show that they have potential for use in vacuum ultraviolet and photovoltaic applications. The mechanical and optical characteristics of the materials are significantly enhanced under pressure.","PeriodicalId":20406,"journal":{"name":"Physica Status Solidi B-basic Solid State Physics","volume":"6 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141872872","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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