Vojtech Vanecek, Vitezslav Jary, Robert Kral, Lubomir Havlak, Ales Vlk, Romana Kucerkova, Petr Prusa, Jan Barta, Martin Nikl
For the first time Lu2S3 (undoped and Pr-doped) single crystals were successfully grown from melt using micro-pulling-down (mPD) technique. Customization of halide mPD apparatus allowed us to grow rod-shaped ({O}2 mm and length around 20 mm) crystals of Lu2S3 with high melting temperature (~1750 {deg}C). X-ray powder diffraction revealed that the grown crystals exhibit the {epsilon}-Lu2S3 crystal structure ({alpha}-Al2O3 type, space group R-3c). Optical and scintillation properties of both the undoped and Pr3+ doped Lu2S3 were investigated. Fast 5d-4f Pr3+ luminescence was observed in both photoluminescence and radioluminescence spectra. The presented technology is an effective tool for the exploration of a large family of high-melting sulfides. Such materials show promise for application as scintillators, active laser media, and optoelectronic components.
{"title":"Growth and Spectroscopic Properties of Pr3+ Doped Lu2S3 SingleCrystals","authors":"Vojtech Vanecek, Vitezslav Jary, Robert Kral, Lubomir Havlak, Ales Vlk, Romana Kucerkova, Petr Prusa, Jan Barta, Martin Nikl","doi":"arxiv-2409.10818","DOIUrl":"https://doi.org/arxiv-2409.10818","url":null,"abstract":"For the first time Lu2S3 (undoped and Pr-doped) single crystals were\u0000successfully grown from melt using micro-pulling-down (mPD) technique.\u0000Customization of halide mPD apparatus allowed us to grow rod-shaped ({O}2 mm\u0000and length around 20 mm) crystals of Lu2S3 with high melting temperature (~1750\u0000{deg}C). X-ray powder diffraction revealed that the grown crystals exhibit the\u0000{epsilon}-Lu2S3 crystal structure ({alpha}-Al2O3 type, space group R-3c).\u0000Optical and scintillation properties of both the undoped and Pr3+ doped Lu2S3\u0000were investigated. Fast 5d-4f Pr3+ luminescence was observed in both\u0000photoluminescence and radioluminescence spectra. The presented technology is an\u0000effective tool for the exploration of a large family of high-melting sulfides.\u0000Such materials show promise for application as scintillators, active laser\u0000media, and optoelectronic components.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kathryn R. Jones, Khanh Dang, Daniel N. Blaschke, Saryu J. Fensin, Abigail Hunter
Theory predicts limiting gliding velocities that dislocations cannot overcome. Computational and recent experiments have shown that these limiting velocities are soft barriers and dislocations can reach transonic speeds in high rate plastic deformation scenarios. In this paper we systematically examine the mobility of edge and screw dislocations in several face centered cubic (FCC) metals (Al, Au, Pt, and Ni) in the extreme large-applied-stress regime using MD simulations. Our results show that edge dislocations are more likely to move at transonic velocities due to their high mobility and lower limiting velocity than screw dislocations. Importantly, among the considered FCC metals, the dislocation core structure determines the dislocation's ability to reach transonic velocities. This is likely due to the variation in stacking fault width (SFW) due to relativistic effects near the limiting velocities.
{"title":"Exploring the relation between transonic dislocation glide and stacking fault width in FCC metals","authors":"Kathryn R. Jones, Khanh Dang, Daniel N. Blaschke, Saryu J. Fensin, Abigail Hunter","doi":"arxiv-2409.10705","DOIUrl":"https://doi.org/arxiv-2409.10705","url":null,"abstract":"Theory predicts limiting gliding velocities that dislocations cannot\u0000overcome. Computational and recent experiments have shown that these limiting\u0000velocities are soft barriers and dislocations can reach transonic speeds in\u0000high rate plastic deformation scenarios. In this paper we systematically\u0000examine the mobility of edge and screw dislocations in several face centered\u0000cubic (FCC) metals (Al, Au, Pt, and Ni) in the extreme large-applied-stress\u0000regime using MD simulations. Our results show that edge dislocations are more\u0000likely to move at transonic velocities due to their high mobility and lower\u0000limiting velocity than screw dislocations. Importantly, among the considered\u0000FCC metals, the dislocation core structure determines the dislocation's ability\u0000to reach transonic velocities. This is likely due to the variation in stacking\u0000fault width (SFW) due to relativistic effects near the limiting velocities.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Isaac de Macêdo Felix, Raphael Matozo Tromer, Leonardo Dantas Machado, Douglas Soares Galvão, Luiz Antônio Ribeiro Jr, Marcelo Lopes Pereira Jr
The thermal conductivity of two-dimensional (2D) materials is critical in determining their suitability for several applications, from electronics to thermal management. In this study, we have used Molecular Dynamics (MD) simulations to investigate the thermal conductivity and phononic properties of 8-16-4(Sun)-Graphyne, a recently proposed 2D carbon allotrope. The thermal conductivity was estimated using reverse non-equilibrium MD simulations following the Muuller-Plathe approach, revealing a strong dependence on system size. Phonon dispersion calculations confirm the stability of Sun-GY while also showing a significant decrease in thermal conductivity compared to graphene. This decrease is attributed to acetylenic bonds, which enhance phonon scattering. Spectral analysis further revealed that Sun-GY exhibits lower phonon group velocities and increased phonon scattering, mainly due to interactions between acoustic and optical modes. Sun-GY presents an intrinsic thermal conductivity of approximately 24.6 W/mK, much lower than graphene, making it a promising candidate for applications that require materials with reduced thermal transport properties.
{"title":"Lattice Thermal Conductivity of Sun-Graphyne from Reverse Nonequilibrium Molecular Dynamics Simulations","authors":"Isaac de Macêdo Felix, Raphael Matozo Tromer, Leonardo Dantas Machado, Douglas Soares Galvão, Luiz Antônio Ribeiro Jr, Marcelo Lopes Pereira Jr","doi":"arxiv-2409.10355","DOIUrl":"https://doi.org/arxiv-2409.10355","url":null,"abstract":"The thermal conductivity of two-dimensional (2D) materials is critical in\u0000determining their suitability for several applications, from electronics to\u0000thermal management. In this study, we have used Molecular Dynamics (MD)\u0000simulations to investigate the thermal conductivity and phononic properties of\u00008-16-4(Sun)-Graphyne, a recently proposed 2D carbon allotrope. The thermal\u0000conductivity was estimated using reverse non-equilibrium MD simulations\u0000following the Muuller-Plathe approach, revealing a strong dependence on system\u0000size. Phonon dispersion calculations confirm the stability of Sun-GY while also\u0000showing a significant decrease in thermal conductivity compared to graphene.\u0000This decrease is attributed to acetylenic bonds, which enhance phonon\u0000scattering. Spectral analysis further revealed that Sun-GY exhibits lower\u0000phonon group velocities and increased phonon scattering, mainly due to\u0000interactions between acoustic and optical modes. Sun-GY presents an intrinsic\u0000thermal conductivity of approximately 24.6 W/mK, much lower than graphene,\u0000making it a promising candidate for applications that require materials with\u0000reduced thermal transport properties.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sachin Krishnia, Libor Vojáček, Tristan Da Câmara Santa Clara Gomes, Nicolas Sebe, Fatima Ibrahim, Jing Li, Luis Moreno Vicente-Arche, Sophie Collin, Thibaud Denneulin, Rafal E. Dunin-Borkowski, Philippe Ohresser, Nicolas Jaouen, André Thiaville, Albert Fert, Henri Jaffrès, Mairbek Chshiev, Nicolas Reyren, Vincent Cros
Perpendicular magnetic anisotropy (PMA) and Dzyaloshinskii-Moriya interactions are key interactions in modern spintronics. These interactions are thought to be dominated by the oxidation of the Co|Al interface in the archetypal Platinum-Cobalt-Aluminum oxide system. Here, we observe a double sign change in the anisotropy and about threefold variation in interfacial chiral interaction, influenced not only by the oxidation, but also by the metallic Al thickness. Contrary to previous assumptions about negligible spin-orbit effects at light metal interfaces, we not only observe strong PMA with fully oxidized Al, decreasing and turning negative (in-plane) with less oxygen at the Co|Al interface, we also observe that the magnetic anisotropy reverts to positive (out-of-plane) values at fully metallic Co|Al interface. These findings suggest modification in Co d band via Co|Al orbital hybridization, an effect supported by X-ray absorption spectroscopy and ab initio theory calculations, highlighting the key impact of strain on interfacial mechanisms at fully metallic Co|Al interface.
{"title":"Interfacial spin-orbitronic effects controlled with different oxidation levels at the Co|Al interface","authors":"Sachin Krishnia, Libor Vojáček, Tristan Da Câmara Santa Clara Gomes, Nicolas Sebe, Fatima Ibrahim, Jing Li, Luis Moreno Vicente-Arche, Sophie Collin, Thibaud Denneulin, Rafal E. Dunin-Borkowski, Philippe Ohresser, Nicolas Jaouen, André Thiaville, Albert Fert, Henri Jaffrès, Mairbek Chshiev, Nicolas Reyren, Vincent Cros","doi":"arxiv-2409.10685","DOIUrl":"https://doi.org/arxiv-2409.10685","url":null,"abstract":"Perpendicular magnetic anisotropy (PMA) and Dzyaloshinskii-Moriya\u0000interactions are key interactions in modern spintronics. These interactions are\u0000thought to be dominated by the oxidation of the Co|Al interface in the\u0000archetypal Platinum-Cobalt-Aluminum oxide system. Here, we observe a double\u0000sign change in the anisotropy and about threefold variation in interfacial\u0000chiral interaction, influenced not only by the oxidation, but also by the\u0000metallic Al thickness. Contrary to previous assumptions about negligible\u0000spin-orbit effects at light metal interfaces, we not only observe strong PMA\u0000with fully oxidized Al, decreasing and turning negative (in-plane) with less\u0000oxygen at the Co|Al interface, we also observe that the magnetic anisotropy\u0000reverts to positive (out-of-plane) values at fully metallic Co|Al interface.\u0000These findings suggest modification in Co d band via Co|Al orbital\u0000hybridization, an effect supported by X-ray absorption spectroscopy and ab\u0000initio theory calculations, highlighting the key impact of strain on\u0000interfacial mechanisms at fully metallic Co|Al interface.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tomas Jungwirth, Rafael M. Fernandes, Jairo Sinova, Libor Smejkal
The recent discovery of altermagnets has opened new perspectives in the field of ordered phases in condensed matter. In strongly-correlated superfluids, the nodal p-wave and d-wave ordered phases of $^{3}$He and cuprates play a prominent role in physics for their rich phenomenology of the symmetry-breaking order parameters. While the p-wave and d-wave superfluids have been extensively studied over the past half a century, material realizations of their magnetic counterparts have remained elusive for many decades. This is resolved in altermagnets, whose recent discovery was driven by research in the field of spintronics towards highly scalable information technologies. Altermagnets feature d, g or i-wave magnetic ordering, with a characteristic alternation of spin polarization and spin-degenerate nodes. Here we review how altermagnetism can be identified from symmetries of collinear spin densities in crystal lattices, and can be realized at normal conditions in a broad family of insulating and conducting materials. We highlight salient electronic-structure signatures of the altermagnetic ordering, discuss extraordinary relativistic and topological phenomena that emerge in their band structures, and comment on strong-correlation effects. We then extend the discussion to non-collinear spin densities in crystals, including the prediction of p-wave magnets, and conclude with a brief summary of the reviewed physical properties of the nodal magnetically-ordered phases.
最近发现的变磁体为凝聚态有序相领域开辟了新的前景。在强相关超流体中,$^{3}$He和铜酸盐的对偶p波和d波有序相因其丰富的对称性破缺阶参数现象学而在物理学中发挥着重要作用。在过去的半个世纪里,人们对 p 波和 d 波超流体进行了广泛的研究,但几十年来,人们对其磁性对应物的物质实现却一直茫然无知。最近,在自旋电子学领域研究高度可扩展信息技术的推动下,人们发现了超磁体。超微磁体具有 d 波、g 波或 i 波磁有序性,并具有自旋极化和自旋退化节点交替的特征。在此,我们回顾了如何从晶格中对偶自旋密度的对称性中识别出另一种磁性,以及如何在各种绝缘和导电材料中实现正常条件下的另一种磁性。我们强调了变磁有序的突出电子结构特征,讨论了其带状结构中出现的非凡相对论和拓扑现象,并对强相关效应进行了评论。然后,我们将讨论扩展到晶体中的非共线性密度,包括对 p 波磁体的预测,最后简要总结了经回顾的节点磁有序相的物理特性。
{"title":"Altermagnets and beyond: Nodal magnetically-ordered phases","authors":"Tomas Jungwirth, Rafael M. Fernandes, Jairo Sinova, Libor Smejkal","doi":"arxiv-2409.10034","DOIUrl":"https://doi.org/arxiv-2409.10034","url":null,"abstract":"The recent discovery of altermagnets has opened new perspectives in the field\u0000of ordered phases in condensed matter. In strongly-correlated superfluids, the\u0000nodal p-wave and d-wave ordered phases of $^{3}$He and cuprates play a\u0000prominent role in physics for their rich phenomenology of the symmetry-breaking\u0000order parameters. While the p-wave and d-wave superfluids have been extensively\u0000studied over the past half a century, material realizations of their magnetic\u0000counterparts have remained elusive for many decades. This is resolved in\u0000altermagnets, whose recent discovery was driven by research in the field of\u0000spintronics towards highly scalable information technologies. Altermagnets\u0000feature d, g or i-wave magnetic ordering, with a characteristic alternation of\u0000spin polarization and spin-degenerate nodes. Here we review how altermagnetism\u0000can be identified from symmetries of collinear spin densities in crystal\u0000lattices, and can be realized at normal conditions in a broad family of\u0000insulating and conducting materials. We highlight salient electronic-structure\u0000signatures of the altermagnetic ordering, discuss extraordinary relativistic\u0000and topological phenomena that emerge in their band structures, and comment on\u0000strong-correlation effects. We then extend the discussion to non-collinear spin\u0000densities in crystals, including the prediction of p-wave magnets, and conclude\u0000with a brief summary of the reviewed physical properties of the nodal\u0000magnetically-ordered phases.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The chirality-induced spin selectivity (CISS) effect has garnered significant interest in the field of molecular spintronics due to its potential for creating spin-polarized electrons without the need for a magnet. Recent studies devoted to CISS effects in various chiral materials demonstrate exciting prospects for spintronics, chiral recognition, and quantum information applications. Several experimental studies have confirmed the applicability of chiral molecules towards spin-filtering properties, influencing spin-polarized electron transport, and photoemission. Researchers aim to predict CISS phenomena and apply this concept to practical applications by compiling experimental results and enhancing understanding of the CISS effect. To expand the possibilities of spin manipulation and create new opportunities for spin-based technologies, researchers are diligently exploring different chiral organic and inorganic materials for probing the CISS effect. This ongoing research holds promise for developing novel spin-based technologies and advancing the understanding of the intricate relationship between chirality and electron spin. This review showcases the remarkable CISS effect and its impact on spintronics, as well as its relevance in various other scientific areas.
{"title":"Spin-controlled Electron transport in Chiral Molecular Assemblies for Various Applications","authors":"Ritu Gupta, Anujit Balo, Rabia Garg, Amit Kumar Mondal, Koyel Banerjee Ghosh, Prakash Chandra Mondal","doi":"arxiv-2409.10036","DOIUrl":"https://doi.org/arxiv-2409.10036","url":null,"abstract":"The chirality-induced spin selectivity (CISS) effect has garnered significant\u0000interest in the field of molecular spintronics due to its potential for\u0000creating spin-polarized electrons without the need for a magnet. Recent studies\u0000devoted to CISS effects in various chiral materials demonstrate exciting\u0000prospects for spintronics, chiral recognition, and quantum information\u0000applications. Several experimental studies have confirmed the applicability of\u0000chiral molecules towards spin-filtering properties, influencing spin-polarized\u0000electron transport, and photoemission. Researchers aim to predict CISS\u0000phenomena and apply this concept to practical applications by compiling\u0000experimental results and enhancing understanding of the CISS effect. To expand\u0000the possibilities of spin manipulation and create new opportunities for\u0000spin-based technologies, researchers are diligently exploring different chiral\u0000organic and inorganic materials for probing the CISS effect. This ongoing\u0000research holds promise for developing novel spin-based technologies and\u0000advancing the understanding of the intricate relationship between chirality and\u0000electron spin. This review showcases the remarkable CISS effect and its impact\u0000on spintronics, as well as its relevance in various other scientific areas.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"209 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hailing Jiang, Tao Wang, Zhenyu Zhang, Ruochen Shi, Xifan Xu, Bowen Sheng, Fang Liu, Weikun Ge, Ping Wang, Bo Shen, Peng Gao, Lucas R Lindsay, Xinqiang Wang
Phonon resistance from dislocation scattering is often divided into short-range core interactions and long-range strain field interactions. Using electron energy-loss spectroscopy on a GaN dislocation, we report observations of vibrational modes localized at specific core atoms (short-range) and strain-driven phonon energy shifts around the dislocation (long-range). Ab initio calculations support these findings and draw out additional details. This study reveals atomically resolved vibrational spectra of dislocations, thus offering insights for engineering improved material functionalities.
位错散射产生的声子阻力通常分为短程核心相互作用和长程应变场相互作用。利用 GaN 位错的电子能量损失光谱,我们报告了在特定核心原子(短程)定位的振动模式和位错周围应变驱动的声子能量移动(长程)的观测结果。这项研究揭示了原子解析的位错振动光谱,从而为改进材料功能的工程设计提供了启示。
{"title":"Single-atom-resolved vibrational spectroscopy of a dislocation","authors":"Hailing Jiang, Tao Wang, Zhenyu Zhang, Ruochen Shi, Xifan Xu, Bowen Sheng, Fang Liu, Weikun Ge, Ping Wang, Bo Shen, Peng Gao, Lucas R Lindsay, Xinqiang Wang","doi":"arxiv-2409.10628","DOIUrl":"https://doi.org/arxiv-2409.10628","url":null,"abstract":"Phonon resistance from dislocation scattering is often divided into\u0000short-range core interactions and long-range strain field interactions. Using\u0000electron energy-loss spectroscopy on a GaN dislocation, we report observations\u0000of vibrational modes localized at specific core atoms (short-range) and\u0000strain-driven phonon energy shifts around the dislocation (long-range). Ab\u0000initio calculations support these findings and draw out additional details.\u0000This study reveals atomically resolved vibrational spectra of dislocations,\u0000thus offering insights for engineering improved material functionalities.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We explore the potential of novel antiperovskite c-Na3HS to be a solid-state electrolyte for sodium-ion batteries. To investigate the dynamical stability, phase stability, thermal stability, mechanical stability and ionic, electronic and diffusive properties of c-Na3HS, the first-principles methods based on density functional theory (DFT) and ab-initio molecular dynamics (AIMD) simulations have been employed. c-Na3HS has no imaginary phonon modes indicating its dynamical stability. Key findings include small energy-above-hull, the wide band gap of 4.35 eV and mechanical stability analysis that indicates the moderately hard and a little brittle nature of c-Na3HS. The activation energy of Na in c-Na3HS is calculated to be ~300 meV that reduces to ~ 100 meV on introducing Na-vacancy. The ionic conductivity can be enhanced up to ~3 order of magnitude by vacancy and halogen doping in c-Na3HS structure. Thus, the obtained results indicate that c-Na3HS can be viable option to be utilized as solid-state electrolyte in sodium-ion batteries.
我们探索了新型反钝角晶c-Na3HS作为钠离子电池固态电解质的潜力。为了研究 c-Na3HS 的动力学稳定性、相稳定性、热稳定性、机械稳定性以及离子、电子和扩散特性,我们采用了基于密度泛函理论(DFT)和非原位分子动力学(AIMD)模拟的第一性原理方法。研究的主要发现包括:壳上能量小、带隙宽达 4.35 eV 以及机械稳定性分析表明 c-Na3HS 具有中等硬度和轻微脆性。根据计算,c-Na3HS 中 Na 的活化能约为 300 meV,而在引入 Na 空性后,活化能将降至约 100 meV。通过在 Na3HS 结构中掺入空位和卤素,离子导电性可提高约 3 个数量级。因此,所得结果表明,c-Na3HS 可以作为钠离子电池的固态电解质。
{"title":"First Principles Insight into Antiperovskite c-Na3HS Solid State Electrolyte","authors":"Sananya Chakraborty, Nidhi Verma, Ashok Kumar","doi":"arxiv-2409.09690","DOIUrl":"https://doi.org/arxiv-2409.09690","url":null,"abstract":"We explore the potential of novel antiperovskite c-Na3HS to be a solid-state\u0000electrolyte for sodium-ion batteries. To investigate the dynamical stability,\u0000phase stability, thermal stability, mechanical stability and ionic, electronic\u0000and diffusive properties of c-Na3HS, the first-principles methods based on\u0000density functional theory (DFT) and ab-initio molecular dynamics (AIMD)\u0000simulations have been employed. c-Na3HS has no imaginary phonon modes\u0000indicating its dynamical stability. Key findings include small\u0000energy-above-hull, the wide band gap of 4.35 eV and mechanical stability\u0000analysis that indicates the moderately hard and a little brittle nature of\u0000c-Na3HS. The activation energy of Na in c-Na3HS is calculated to be ~300 meV\u0000that reduces to ~ 100 meV on introducing Na-vacancy. The ionic conductivity can\u0000be enhanced up to ~3 order of magnitude by vacancy and halogen doping in\u0000c-Na3HS structure. Thus, the obtained results indicate that c-Na3HS can be\u0000viable option to be utilized as solid-state electrolyte in sodium-ion\u0000batteries.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study explores the structural stability, elastic, mechanical, electronic, thermophysical, magnetic, optical and lattice dynamic properties of VPdZ (Z= Ge, Sn) half Heusler alloys using density functional theory. The alloys show stability in type-{alpha} ferromagnetic phase and have half-metallic band topologies. The half-metallic feature is indicated by the spin-polarized behavior that is revealed by the detailed profiles of the electronic band structures. According to the electronic band profiles both alloys are half-metallic, with indirect energy gaps in the spin down channel of 1.10 eV and 1.02 eV for VPdGe and VPdSn half Heusler alloys respectively. The Quasi-Harmonic Debye model helps study thermodynamic parameters, and the magnetic moment values align with the Slater-Pauling rule. The alloys have potential applications in thermodynamic, spintronic, and optoelectronic fields.
{"title":"First Principle Analysis of Novel Half Heusler Alloys VPdZ (Z= Ge, Sn) for thermodynamic, spintronics and optoelectronic applications","authors":"Ashwani Kumar, Shyam Lal Gupta, Sumit Kumar, Anupam, Diwaker","doi":"arxiv-2409.09735","DOIUrl":"https://doi.org/arxiv-2409.09735","url":null,"abstract":"This study explores the structural stability, elastic, mechanical,\u0000electronic, thermophysical, magnetic, optical and lattice dynamic properties of\u0000VPdZ (Z= Ge, Sn) half Heusler alloys using density functional theory. The\u0000alloys show stability in type-{alpha} ferromagnetic phase and have\u0000half-metallic band topologies. The half-metallic feature is indicated by the\u0000spin-polarized behavior that is revealed by the detailed profiles of the\u0000electronic band structures. According to the electronic band profiles both\u0000alloys are half-metallic, with indirect energy gaps in the spin down channel of\u00001.10 eV and 1.02 eV for VPdGe and VPdSn half Heusler alloys respectively. The\u0000Quasi-Harmonic Debye model helps study thermodynamic parameters, and the\u0000magnetic moment values align with the Slater-Pauling rule. The alloys have\u0000potential applications in thermodynamic, spintronic, and optoelectronic fields.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"105 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
All-d-metal full-Heusler alloys possess superior mechanical properties and high spin polarization, which would play an important role in spintronic applications. Despite this, their electrical and thermal transport properties have not been comprehensively investigated till now. In this work, we present an analysis on the evolution of structural, magnetic and transport properties of Cr- and Ti-substituted Fe2CrV all-d-metal Heusler alloys by combining theoretical calculations and experiments. Both series of alloys crystallize in Hg2CuTi-type structure. With increasing Ti doping, the calculated total magnetic moments of Fe50Cr25V25-xTix decrease linearly. The experimental saturation magnetization is highly consistent with theoretical calculations and Slater-Pauling rule when x < 4, indicating the highly ordered atomic occupation. The magnetization and Curie temperature can be significantly tuned by altering spin polarizations and exchange interactions. The introduction of the foreign atom, Ti, results in a linear increase in residual resistivity, while electron-phonon scattering keeps relatively constant. The maximum values for electrical and thermal transport properties are observed in the stoichiometric Fe2CrV composition.
全 D 金属全赫斯勒合金具有优异的机械性能和高自旋极化,这将在自旋电子应用中发挥重要作用。尽管如此,迄今为止,人们尚未对它们的电学和热学传输特性进行全面研究。在这项研究中,我们结合理论计算和实验,分析了 Cr- 和 Ti 取代的 Fe2CrV 全 D 金属 Heusler 合金的结构、磁性和传输特性的演变。这两个系列的合金都结晶成 Hg2CuTi- 型结构。随着钛掺杂量的增加,Fe50Cr25V25-xTix 的计算总磁矩呈线性下降。当 x < 4 时,实验饱和磁化率与理论计算结果和斯莱特-保龄法则高度一致,表明原子占据高度有序。磁化和居里温度可以通过改变自旋极化和交换相互作用进行显著调整。引入外来原子 Ti 会导致残余电阻率线性增加,而电子-声子散射则保持相对恒定。电学和热学传输特性的最大值出现在铁/铬/钒的化学成分中。
{"title":"Evolution of structure, magnetism, and electronic/thermal-transports of Ti(Cr)-substituted Fe2CrV all-d-metal Heusler ferromagnets","authors":"Yiting Feng, Shen Zhang, Qingqi Zeng, Meng Lyu, Junyan Liu, Jinying Yang, Yibo Wang, Qiusa Ren, Yang Liu, Binbin Wang, Hongxiang Wei, Enke Liu","doi":"arxiv-2409.09718","DOIUrl":"https://doi.org/arxiv-2409.09718","url":null,"abstract":"All-d-metal full-Heusler alloys possess superior mechanical properties and\u0000high spin polarization, which would play an important role in spintronic\u0000applications. Despite this, their electrical and thermal transport properties\u0000have not been comprehensively investigated till now. In this work, we present\u0000an analysis on the evolution of structural, magnetic and transport properties\u0000of Cr- and Ti-substituted Fe2CrV all-d-metal Heusler alloys by combining\u0000theoretical calculations and experiments. Both series of alloys crystallize in\u0000Hg2CuTi-type structure. With increasing Ti doping, the calculated total\u0000magnetic moments of Fe50Cr25V25-xTix decrease linearly. The experimental\u0000saturation magnetization is highly consistent with theoretical calculations and\u0000Slater-Pauling rule when x < 4, indicating the highly ordered atomic\u0000occupation. The magnetization and Curie temperature can be significantly tuned\u0000by altering spin polarizations and exchange interactions. The introduction of\u0000the foreign atom, Ti, results in a linear increase in residual resistivity,\u0000while electron-phonon scattering keeps relatively constant. The maximum values\u0000for electrical and thermal transport properties are observed in the\u0000stoichiometric Fe2CrV composition.","PeriodicalId":501234,"journal":{"name":"arXiv - PHYS - Materials Science","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142268226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}