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Surface phase diagram of CsSnI3 from first-principles calculations 第一原理计算得出的 CsSnI3 表面相图
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-05 DOI: 10.1103/physrevmaterials.8.093401
Kejia Li, Chadawan Khamdang, Mengen Wang
CsSnI3 is widely studied as an environmentally friendly Pb-free perovskite material for optoelectronic device applications. To further improve material and device performance, it is important to understand the surface structures of CsSnI3. We generate surface structures with various stoichiometries, perform density functional theory calculations to create phase diagrams of the CsSnI3 (001), (110), and (100) surfaces, and determine the most stable surfaces under a wide range of Cs, Sn, and I chemical potentials. Under I-rich conditions, surfaces with Cs vacancies are stable, which lead to partially occupied surface states above the valence band maximum. Under I-poor conditions, we find the stoichiometric (100) surface to be stable under a wide region of the phase diagram, which does not have any surface states and can contribute to long charge-carrier lifetimes. Consequently, the I-poor (Sn-rich) conditions will be more beneficial to improve the device performance.
CsSnI3 作为一种用于光电器件应用的环保型无铅包晶材料,已被广泛研究。为了进一步提高材料和器件的性能,了解 CsSnI3 的表面结构非常重要。我们生成了具有各种化学计量的表面结构,进行了密度泛函理论计算,绘制了 CsSnI3 (001)、(110) 和 (100) 表面的相图,并确定了在各种 Cs、Sn 和 I 化学势下最稳定的表面。在 I 丰富的条件下,具有铯空位的表面是稳定的,这会导致价带最大值以上的部分占据表面态。在 I 贫乏的条件下,我们发现化学计量(100)表面在相图的很宽区域内是稳定的,它没有任何表面态,可导致较长的电荷载流子寿命。因此,贫离子(富含锡)条件更有利于提高器件性能。
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引用次数: 0
Layer dependent topological phases and transitions in TaRhTe4: From monolayer and bilayer to bulk TaRhTe4 中与层相关的拓扑相和转变:从单层和双层到块体
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-03 DOI: 10.1103/physrevmaterials.8.094201
Xiao Zhang, Ning Mao, Oleg Janson, Jeroen van den Brink, Rajyavardhan Ray
The recently synthesized ternary quasi-2D material TaRhTe4 is a bulk Weyl semimetal with an intrinsically layered structure, which poses the question of how the topology of its electronic structure depends on layer separations. Experimentally, these separations may be changed for instance by intercalation of the bulk, or by exfoliation, to reach monolayer or few-layer structures. Here, we show that in the monolayer limit a quantum spin Hall insulator (QSHI) state emerges, employing density functional calculations as well as a minimal four-orbital tight-binding model that we develop. Even for weak spin-orbit couplings the QSHI is present, which has an interesting edge state that features Rashba-split bands with quadratic band minima. Further, we find that a weak topological insulator (WTI) manifests in the bilayer system due to sizable intralayer hopping, contrary to the common lore that only weak interlayer interactions between stacked QSHIs lead to WTIs. Stacked bilayers give rise to a phase diagram as a function of the interlayer separation that comprises a Weyl semimetal, WTI, and normal insulator (NI) phases. These insights on the evolution of topology with dimensions can be transferred to the family of layered ternary transition metal tellurides.
最近合成的三元准二维材料 TaRhTe4 是一种具有固有层状结构的体韦尔半金属,这就提出了一个问题:其电子结构的拓扑如何取决于层的分离。在实验中,可以通过体层插层或剥离等方法改变这些分隔,从而达到单层或少层结构。在这里,我们利用密度泛函计算以及我们开发的最小四轨道紧密结合模型,证明在单层极限下会出现量子自旋霍尔绝缘体(QSHI)状态。即使在弱自旋轨道耦合的情况下,QSHI 也会出现,它有一个有趣的边缘态,其特征是具有二次带极小值的拉什巴分裂带。此外,我们还发现双层体系中会出现弱拓扑绝缘体 (WTI),这是由于层内跳变的影响,这与通常认为只有堆叠的 QSHIs 之间的弱层间相互作用才会导致 WTI 的说法相反。堆叠双层膜产生的相图是层间分离的函数,其中包括韦尔半金属、WTI 和正常绝缘体 (NI) 相。这些关于拓扑结构随尺寸演变的见解可以应用到层状三元过渡金属碲家族中。
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引用次数: 0
Optimizing the adsorption strength of oxygen intermediates on NiCo2O4 by Fe doping to improve the oxygen evolution reaction performance 通过掺杂铁优化镍钴氧化物对氧中间体的吸附强度以改善氧进化反应性能
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-03 DOI: 10.1103/physrevmaterials.8.095801
Xilin Zhang, Rui Song, Yanyan Zhai, Rui Zheng, Shan Wang, Zhongjun Ma, Zongxian Yang
Spinel oxide (NiCo2O4) is an attractive catalyst for oxygen evolution reaction (OER) due to its rich redox reactions and unique electronic structure. However, the electrocatalytic OER performance of NiCo2O4 has always been limited by the low specific surface area and poor intrinsic conductivity of NiCo2O4. Cationic doping is an effective method in modulating the electrocatalytic activity at the atomic level to improve the conductivity and activity. Herein, a series of Fe-doped NiCo2O4 electrocatalysts were successfully prepared using a simple solvothermal method. Impressively, Fe-doped NiCo2O4 delivers an attractive small overpotential of 341 mV at 10mAcm2 and a Tafel slope of 74mVdec1 compared to NiCo2O4. The x-ray photoelectron spectroscopy and the density functional theory calculations reveal that Fe dopants can regulate the electronic structure of Ni sites by donating electrons to Co atoms, which leads to an increased Ni3+ ratio and a reduced adsorption strength of oxygen intermediates at Ni sites, thus facilitating the conversion of *OH to *O. This work provides an effective approach to enhancing the electrocatalytic activities of non-noble-metal-based catalysts.
尖晶石氧化物(NiCo2O4)具有丰富的氧化还原反应和独特的电子结构,是一种极具吸引力的氧进化反应催化剂。然而,由于镍钴氧化物的比表面积低、内在电导率差,其电催化 OER 的性能一直受到限制。阳离子掺杂是在原子水平上调节电催化活性以提高电导率和活性的有效方法。本文采用简单的溶热法成功制备了一系列掺杂 Fe 的 NiCo2O4 电催化剂。令人印象深刻的是,与镍钴氧化物相比,掺杂铁的镍钴氧化物在 10mAcm-2 条件下具有 341 mV 的极小过电位和 74mVdec-1 的塔菲尔斜率。X 射线光电子能谱和密度泛函理论计算显示,掺杂铁元素可以通过向 Co 原子捐献电子来调节 Ni 位点的电子结构,从而导致 Ni3+ 比率增加,氧中间产物在 Ni 位点的吸附强度降低,从而促进 *OH 向 *O 的转化。这项工作为提高非贵金属基催化剂的电催化活性提供了一种有效的方法。
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引用次数: 0
Theoretical and experimental investigations on Fe2P-type magnets: Effects of Si and Co substitution on physical and magnetic properties 关于 Fe2P 型磁体的理论和实验研究:硅和钴的替代对物理和磁性能的影响
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-03 DOI: 10.1103/physrevmaterials.8.094401
Stephan Erdmann, Halil İbrahim Sözen, Francois Guillou, Hargen Yibole, Thorsten Klüner
<math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Fe</mi><mn>2</mn></msub><mi mathvariant="normal">P</mi></mrow></math>-based magnets are known for their significant magnetic properties, making them useful in various technological applications. The aim of this study was to investigate the effects of Si and Co substitution on the physical and magnetic properties of the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Fe</mi><mn>2</mn></msub><mi mathvariant="normal">P</mi></mrow></math> compounds. In order to have a systematic understanding we have performed combined <i>ab initio</i> calculations and a set of experiments. Particular emphasis was placed on the study of preferential substitution sites, lattice constants, magnetic moments, and the Curie temperature (<math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>T</mi><mi>C</mi></msub></math>), which was further explored by considering the exchange interaction energies <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>J</mi><mrow><mi>i</mi><mi>j</mi></mrow></msub></math>. Satisfactory agreement was observed between theoretical calculations and the predicted phase transition from the hexagonal to the body-centered-orthorhombic (BCO) crystal structure as a function of temperature. Theoretical calculations reveal that the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>2</mn><mi>c</mi></mrow></math> position is the preferred site for Si, while Co is expected to occupy the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>3</mn><mi>f</mi></mrow></math> sites. Theoretical analysis of the magnetic moments shows an increase up to <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>3.64</mn><mspace width="0.16em"></mspace><msub><mi>μ</mi><mi>B</mi></msub><mo>/</mo><mrow><mi mathvariant="normal">f</mi><mo>.</mo><mi mathvariant="normal">u</mi><mo>.</mo></mrow></mrow></math> for <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>x</mi></mrow></math> = 0.5 Si, which agrees with the experimental values of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>3.16</mn><mspace width="0.16em"></mspace><msub><mi>μ</mi><mi>B</mi></msub><mo>/</mo><mrow><mi mathvariant="normal">f</mi><mo>.</mo><mi mathvariant="normal">u</mi><mo>.</mo></mrow></mrow></math> Co substitution in <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Fe</mi><mrow><mn>2</mn><mo>−</mo><mi>y</mi></mrow></msub><msub><mi>Co</mi><mi>y</mi></msub><msub><mi mathvariant="normal">P</mi><mrow><mn>0.84</mn></mrow></msub><msub><mi>Si</mi><mrow><mn>0.16</mn></mrow></msub></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Fe</mi><mrow><mn>2</mn><mo>−</mo><mi>y</mi></mrow></msub><msub><mi>Co</mi><mi>y</mi></msub><msub><mi mathvariant="normal">P</mi><mrow><mn>0.59</mn></mrow></msub><msub><mi>Si</mi><mrow><mn>0.41</mn></mrow></msub></mrow></math> resulted in a decrease in magnetic moments and consequently in other magnetic prope
众所周知,Fe2P 基磁体具有显著的磁性能,因此在各种技术应用中都非常有用。本研究旨在探讨硅和钴的替代对 Fe2P 化合物物理和磁性能的影响。为了对其有一个系统的了解,我们结合了 ab initio 计算和一系列实验。重点研究了优先取代位点、晶格常数、磁矩和居里温度 (TC),并通过考虑交换相互作用能 Jij 进一步探讨了居里温度。理论计算结果与预测的从六方晶体结构到体心正方体(BCO)晶体结构的相变随温度变化的函数之间存在令人满意的一致性。理论计算显示,2c 位是硅的首选位置,而 Co 预计会占据 3f 位。在 Fe2-yCoyP0.84Si0.16 和 Fe2-yCoyP0.59Si0.41 中取代 Co 会导致磁矩减小,从而降低其他磁性能。在居里温度方面,根据硅浓度的不同,发现了三种不同的趋势。3f-3f 层内交换相互作用能量对 Si 的依赖性被认为是这些趋势的原因,并被推断为低浓度 Si 时 TC 增加、中浓度 Si 时 TC 不变以及高浓度 Si 时 TC 降低的原因。
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The aim of this study was to investigate the effects of Si and Co substitution on the physical and magnetic properties of the &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Fe&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi mathvariant=\"normal\"&gt;P&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; compounds. In order to have a systematic understanding we have performed combined &lt;i&gt;ab initio&lt;/i&gt; calculations and a set of experiments. Particular emphasis was placed on the study of preferential substitution sites, lattice constants, magnetic moments, and the Curie temperature (&lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;msub&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;mi&gt;C&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;), which was further explored by considering the exchange interaction energies &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;msub&gt;&lt;mi&gt;J&lt;/mi&gt;&lt;mrow&gt;&lt;mi&gt;i&lt;/mi&gt;&lt;mi&gt;j&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;. Satisfactory agreement was observed between theoretical calculations and the predicted phase transition from the hexagonal to the body-centered-orthorhombic (BCO) crystal structure as a function of temperature. Theoretical calculations reveal that the &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mi&gt;c&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; position is the preferred site for Si, while Co is expected to occupy the &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; sites. Theoretical analysis of the magnetic moments shows an increase up to &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;3.64&lt;/mn&gt;&lt;mspace width=\"0.16em\"&gt;&lt;/mspace&gt;&lt;msub&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mrow&gt;&lt;mi mathvariant=\"normal\"&gt;f&lt;/mi&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mi mathvariant=\"normal\"&gt;u&lt;/mi&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt; for &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mi&gt;x&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; = 0.5 Si, which agrees with the experimental values of &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;3.16&lt;/mn&gt;&lt;mspace width=\"0.16em\"&gt;&lt;/mspace&gt;&lt;msub&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mi&gt;B&lt;/mi&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mrow&gt;&lt;mi mathvariant=\"normal\"&gt;f&lt;/mi&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;mi mathvariant=\"normal\"&gt;u&lt;/mi&gt;&lt;mo&gt;.&lt;/mo&gt;&lt;/mrow&gt;&lt;/mrow&gt;&lt;/math&gt; Co substitution in &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Fe&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi&gt;Co&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi mathvariant=\"normal\"&gt;P&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;0.84&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi&gt;Si&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;0.16&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; and &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Fe&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi&gt;Co&lt;/mi&gt;&lt;mi&gt;y&lt;/mi&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi mathvariant=\"normal\"&gt;P&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;0.59&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi&gt;Si&lt;/mi&gt;&lt;mrow&gt;&lt;mn&gt;0.41&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; resulted in a decrease in magnetic moments and consequently in other magnetic prope","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"180 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Bonding hierarchy and coordination interaction leading to high thermoelectricity in wide bandgap TlAgI2 导致宽带隙 TlAgI2 产生高热电效应的键合层次和配位相互作用
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-03 DOI: 10.1103/physrevmaterials.8.094601
Xiaoying Wang, Mengyang Li, Minxuan Feng, Xuejie Li, Yuzhou Hao, Wen Shi, Jiangang He, Xiangdong Ding, Zhibin Gao
High thermoelectric properties are associated with the phonon-glass electron-crystal paradigm. Conventional wisdom suggests that the optimal bandgap of semiconductor to achieve the largest power factor should be between 6 and 10κBT. To address challenges related to the bipolar effect and temperature limitations, we present findings on Zintl-type TlAgI2, which demonstrates an exceptionally low lattice thermal conductivity of 0.30 W m1K1 at 300 K. The achieved figure of merit (ZT) for TlAgI2, featuring a 2.40 eV bandgap, reaches a value of 1.53 for p-type semiconductor. This remarkable ZT is attributed to the existence of extended antibonding states [Ag-I] in the valence band. Furthermore, the bonding hierarchy, influencing phonon anharmonicity, and coordination bonds, facilitating electron transfer between the ligand and the central metal ion, significantly contribute to the electronic transport. This finding serves as a promising avenue for the development of high ZT materials with wide bandgaps at elevated temperatures.
高热电特性与声子玻璃电子晶体范例有关。传统观点认为,要达到最大功率因数,半导体的最佳带隙应在 6 到 10κBT 之间。为了应对与双极效应和温度限制有关的挑战,我们展示了对 Zintl 型 TlAgI2 的研究结果,它在 300 K 时的晶格热导率非常低,仅为 0.30 W m-1K-1。这一显著的 ZT 值归因于价带中存在扩展的反键态 [Ag-I]。此外,影响声子非谐波性的成键层次和促进配体与中心金属离子间电子转移的配位键也对电子传输起了重要作用。这一发现为在高温下开发具有宽带隙的高 ZT 材料提供了一个很好的途径。
{"title":"Bonding hierarchy and coordination interaction leading to high thermoelectricity in wide bandgap TlAgI2","authors":"Xiaoying Wang, Mengyang Li, Minxuan Feng, Xuejie Li, Yuzhou Hao, Wen Shi, Jiangang He, Xiangdong Ding, Zhibin Gao","doi":"10.1103/physrevmaterials.8.094601","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.094601","url":null,"abstract":"High thermoelectric properties are associated with the phonon-glass electron-crystal paradigm. Conventional wisdom suggests that the optimal bandgap of semiconductor to achieve the largest power factor should be between 6 and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>10</mn><msub><mi>κ</mi><mi>B</mi></msub><mi>T</mi></mrow></math>. To address challenges related to the bipolar effect and temperature limitations, we present findings on Zintl-type <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>TlAgI</mi><mn>2</mn></msub></math>, which demonstrates an exceptionally low lattice thermal conductivity of 0.30 W <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msup><mrow><mi mathvariant=\"normal\">m</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup><mspace width=\"4pt\"></mspace><msup><mrow><mi mathvariant=\"normal\">K</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math> at 300 K. The achieved figure of merit (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Z</mi><mi>T</mi></mrow></math>) for <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>TlAgI</mi><mn>2</mn></msub></math>, featuring a 2.40 eV bandgap, reaches a value of 1.53 for <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>p</mi></math>-type semiconductor. This remarkable <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Z</mi><mi>T</mi></mrow></math> is attributed to the existence of extended antibonding states [Ag-I] in the valence band. Furthermore, the bonding hierarchy, influencing phonon anharmonicity, and coordination bonds, facilitating electron transfer between the ligand and the central metal ion, significantly contribute to the electronic transport. This finding serves as a promising avenue for the development of high <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Z</mi><mi>T</mi></mrow></math> materials with wide bandgaps at elevated temperatures.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"7 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Continuous structural phase transition and antiferromagnetic order in ilmenite-type NiVO3 钛铁矿型 NiVO3 中的连续结构相变和反铁磁秩序
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-09-03 DOI: 10.1103/physrevmaterials.8.094402
Hajime Yamamoto, Osamu Ikeda, Takashi Honda, Kenta Kimura, Takuya Aoyama, Kenya Ohgushi, Akio Suzuki, Kenji Ishii, Daiju Matsumura, Takuya Tsuji, Shintaro Kobayashi, Shogo Kawaguchi, Matteo d’Astuto, Tadashi Abukawa
We investigate the crystal and electronic structures as well as magnetic properties of ilmenite-type NiVO3, which has attracted research interest as an S = 1 honeycomb lattice magnet. Ilmenite-type NiVO3 samples were synthesized under high-pressure and high-temperature conditions. Synchrotron x-ray diffraction and Rietveld refinement results demonstrated that NiVO3 underwent a continuous structural phase transition from the triclinic (P1¯) phase to the rhombohedral (R3¯) phase at 450 K. This transition is concomitant with the decomposition of the V-V dimers formed by the tetravalent V ions. X-ray absorption spectroscopy measurements confirmed that the Ni and V ions were divalent and tetravalent, respectively. Magnetic and specific heat measurements revealed that NiVO3 underwent an antiferromagnetic transition at 140 K, and a zigzag-type magnetic order with magnetic propagation vector k=(0,1/2,0) was observed by neutron diffraction measurements.
我们研究了钛铁矿型 NiVO3 的晶体和电子结构以及磁性能,它作为一种 S = 1 蜂窝晶格磁体引起了研究兴趣。钛铁矿型 NiVO3 样品是在高压和高温条件下合成的。同步辐射 X 射线衍射和里特维尔德细化结果表明,NiVO3 在 450 K 时经历了从三菱(P1¯)相到斜方体(R3¯)相的连续结构相变。X 射线吸收光谱测量证实,镍离子和 V 离子分别为二价和四价。磁性和比热测量结果表明,NiVO3 在 140 K 时发生了反铁磁转变,中子衍射测量观察到磁传播矢量 k=(0,1/2,0) 的人字形磁序。
{"title":"Continuous structural phase transition and antiferromagnetic order in ilmenite-type NiVO3","authors":"Hajime Yamamoto, Osamu Ikeda, Takashi Honda, Kenta Kimura, Takuya Aoyama, Kenya Ohgushi, Akio Suzuki, Kenji Ishii, Daiju Matsumura, Takuya Tsuji, Shintaro Kobayashi, Shogo Kawaguchi, Matteo d’Astuto, Tadashi Abukawa","doi":"10.1103/physrevmaterials.8.094402","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.094402","url":null,"abstract":"We investigate the crystal and electronic structures as well as magnetic properties of ilmenite-type <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>NiV</mi><msub><mi mathvariant=\"normal\">O</mi><mn>3</mn></msub></mrow></math>, which has attracted research interest as an <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>S</mi></mrow></math> = 1 honeycomb lattice magnet. Ilmenite-type <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>NiV</mi><msub><mi mathvariant=\"normal\">O</mi><mn>3</mn></msub></mrow></math> samples were synthesized under high-pressure and high-temperature conditions. Synchrotron x-ray diffraction and Rietveld refinement results demonstrated that <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>NiV</mi><msub><mi mathvariant=\"normal\">O</mi><mn>3</mn></msub></mrow></math> underwent a continuous structural phase transition from the triclinic (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>P</mi></mrow><mover accent=\"true\"><mn>1</mn><mo>¯</mo></mover></math>) phase to the rhombohedral (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>R</mi></mrow><mover accent=\"true\"><mn>3</mn><mo>¯</mo></mover></math>) phase at 450 K. This transition is concomitant with the decomposition of the V-V dimers formed by the tetravalent V ions. X-ray absorption spectroscopy measurements confirmed that the Ni and V ions were divalent and tetravalent, respectively. Magnetic and specific heat measurements revealed that <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>NiV</mi><msub><mi mathvariant=\"normal\">O</mi><mn>3</mn></msub></mrow></math> underwent an antiferromagnetic transition at 140 K, and a zigzag-type magnetic order with magnetic propagation vector <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>k</mi><mo>=</mo><mo>(</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>/</mo><mn>2</mn><mo>,</mo><mn>0</mn><mo>)</mo></mrow></math> was observed by neutron diffraction measurements.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"32 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Magnetic anisotropy in single-crystalline antiferromagnetic Mn2Au 单晶反铁磁性 Mn2Au 中的磁各向异性
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-08-30 DOI: 10.1103/physrevmaterials.8.084413
Mebatsion S. Gebre, Rebecca K. Banner, Kisung Kang, Kejian Qu, Huibo Cao, André Schleife, Daniel P. Shoemaker
Multiple recent studies have identified the metallic antiferromagnet <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> to be a candidate for spintronic applications due to apparent in-plane anisotropy, preserved magnetic properties above room temperature, and current-induced Néel vector switching. Crystal growth is complicated by the fact that <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> melts incongruently. We present a bismuth flux method to grow millimeter-scale bulk single crystals of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> in order to examine the intrinsic anisotropic electrical and magnetic properties. Flux quenching experiments reveal that the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> crystals precipitate below <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>550</mn><msup><mspace width="0.16em"></mspace><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></math>, about <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>100</mn><msup><mspace width="0.16em"></mspace><mo>∘</mo></msup><mi mathvariant="normal">C</mi></mrow></math> below the decomposition temperature of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math>. Bulk <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> crystals have a room-temperature resistivity of 16–19 <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>µ</mi><mi mathvariant="normal">Ω</mi><mspace width="0.16em"></mspace><mi>cm</mi></mrow></math> and a residual resistivity ratio of 41. <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> crystals have a dimensionless susceptibility on the order of <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math> (SI units), comparable to calculated and experimental reports on powder samples. Single-crystal neutron diffraction confirms the in-plane magnetic structure. The tetragonal symmetry of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>Mn</mi><mn>2</mn></msub><mi>Au</mi></mrow></math> constrains the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>a</mi><mi>b</mi></mrow></math>-plane magnetic susceptibility to be constant, meaning that <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>χ</mi><mn>100</mn></msub><mo>=</mo><msub><mi>χ</mi><mn>110</mn></msub></mrow></math> in the low-field limit, below any spin-flop transition. We find that three measured magnetic susceptibilities <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mi>χ</mi><mn>100</mn></msub><mo>,</mo><mo> </mo><msub
最近的多项研究发现,金属反铁磁体 Mn2Au 具有明显的面内各向异性、在室温以上仍保持磁性能以及电流诱导的奈尔矢量开关,因此是自旋电子应用的候选材料。由于 Mn2Au 的熔化不协调,晶体生长变得复杂。我们提出了一种铋通量法来生长毫米级的 Mn2Au 块状单晶体,以研究其内在各向异性的电学和磁学特性。通量淬火实验显示,Mn2Au 晶体在 550∘C以下析出,比 Mn2Au 的分解温度低约 100∘C。块状 Mn2Au 晶体的室温电阻率为 16-19 µΩcm,残余电阻率比为 41。Mn2Au 晶体的无量纲电感值为 10-4(国际单位制),与粉末样品的计算和实验报告相当。单晶中子衍射证实了面内磁性结构。Mn2Au 的四方对称性限制了非平面磁感应强度为常数,这意味着在低磁场极限,即任何自旋翻转转变以下,χ100=χ110。我们发现,测量到的三个磁感应强度 χ100、χ110 和 χ001 数量级相同,并且与计算预测一致,这意味着 Mn2Au 的低场磁感应强度是相当各向同性的,尽管 ab 平面和 ac 平面磁晶各向异性存在明显差异。根据计算,Mn2Au 在 30 T 以上具有极高的面内自旋翻转场,远大于另一种面内反铁磁体 Fe2As(小于 1 T)。本征电感的微妙各向异性可能会导致在 Mn2Au 中尝试自旋读出的设备中,形状、晶体纹理、应变和缺陷产生主导效应。
{"title":"Magnetic anisotropy in single-crystalline antiferromagnetic Mn2Au","authors":"Mebatsion S. Gebre, Rebecca K. Banner, Kisung Kang, Kejian Qu, Huibo Cao, André Schleife, Daniel P. Shoemaker","doi":"10.1103/physrevmaterials.8.084413","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084413","url":null,"abstract":"Multiple recent studies have identified the metallic antiferromagnet &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; to be a candidate for spintronic applications due to apparent in-plane anisotropy, preserved magnetic properties above room temperature, and current-induced Néel vector switching. Crystal growth is complicated by the fact that &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; melts incongruently. We present a bismuth flux method to grow millimeter-scale bulk single crystals of &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; in order to examine the intrinsic anisotropic electrical and magnetic properties. Flux quenching experiments reveal that the &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; crystals precipitate below &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;550&lt;/mn&gt;&lt;msup&gt;&lt;mspace width=\"0.16em\"&gt;&lt;/mspace&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/msup&gt;&lt;mi mathvariant=\"normal\"&gt;C&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;, about &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mn&gt;100&lt;/mn&gt;&lt;msup&gt;&lt;mspace width=\"0.16em\"&gt;&lt;/mspace&gt;&lt;mo&gt;∘&lt;/mo&gt;&lt;/msup&gt;&lt;mi mathvariant=\"normal\"&gt;C&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; below the decomposition temperature of &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;. Bulk &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; crystals have a room-temperature resistivity of 16–19 &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mi&gt;µ&lt;/mi&gt;&lt;mi mathvariant=\"normal\"&gt;Ω&lt;/mi&gt;&lt;mspace width=\"0.16em\"&gt;&lt;/mspace&gt;&lt;mi&gt;cm&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; and a residual resistivity ratio of 41. &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; crystals have a dimensionless susceptibility on the order of &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;msup&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt; (SI units), comparable to calculated and experimental reports on powder samples. Single-crystal neutron diffraction confirms the in-plane magnetic structure. The tetragonal symmetry of &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;Mn&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;Au&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt; constrains the &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;b&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;-plane magnetic susceptibility to be constant, meaning that &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;χ&lt;/mi&gt;&lt;mn&gt;100&lt;/mn&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;χ&lt;/mi&gt;&lt;mn&gt;110&lt;/mn&gt;&lt;/msub&gt;&lt;/mrow&gt;&lt;/math&gt; in the low-field limit, below any spin-flop transition. We find that three measured magnetic susceptibilities &lt;math xmlns=\"http://www.w3.org/1998/Math/MathML\"&gt;&lt;msub&gt;&lt;mi&gt;χ&lt;/mi&gt;&lt;mn&gt;100&lt;/mn&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mo&gt; &lt;/mo&gt;&lt;msub","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"11 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Optical absorption study of iron-substituted zirconia and yttria-stabilized zirconia using experimental measurements and many-body perturbation theory 利用实验测量和多体扰动理论研究铁取代氧化锆和钇稳定氧化锆的光学吸收
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-08-29 DOI: 10.1103/physrevmaterials.8.085203
Shunshun Liu, Victor K. Champagne, III, David R. Clarke, Prasanna V. Balachandran
Yttria-stabilized zirconia (YSZ) coatings have been developed for high temperature energy applications including gas turbines. The objective of this work is to understand how aliovalent Fe substitution affects the optical absorption spectrum of the host YSZ and ZrO2 systems in the ultraviolet–visible–near infrared wavelength range (from 245 to 2500 nm) using both experimental and computational techniques. In the Fe-substituted ZrO2 system, phase-pure (>99% purity) samples were synthesized in the monoclinic crystal structure, whereas Fe substitution in YSZ resulted in a two-phase mixture of coexisting tetragonal and monoclinic phases. Optical property characterization performed at room temperature revealed two broad absorption bands in both systems: one centered around 1000 nm and the other centered around 500 nm. Tauc plot analysis of the optical absorption data showed that as the Fe concentration increases, the optical band gaps of both materials systems decrease. Many-body perturbation theory methods, based on G0W0 and the Bethe-Salpeter equation, were used to computationally model the optical absorption spectrum as a function of Fe substitution in the tetragonal and monoclinic crystal structures of YSZ and ZrO2. Supercells were constructed and several Fe- and/or Y-atom configurations were explored in Zr sites. Charge compensating O vacancies were introduced to maintain electrical neutrality. The computations reveal that the observed optical excitations centered around 1000 nm likely have an excitonic character due to defect states, whose origin is traced to the electronic transitions between Fe3d and Fe3d orbitals. Intriguingly, both the tetragonal and monoclinic crystal structures appear to support local polyhedral distortions that promote excitations in the 1000 nm wavelength region. The excitation centered around 500 nm is attributed to the optical band gap of these materials. The outcomes of this work shed light on the radiative properties of Fe-substituted YSZ with implications in thermal barrier coating composition design.
钇稳定氧化锆(YSZ)涂层已被开发用于高温能源应用,包括燃气轮机。这项工作的目的是利用实验和计算技术,了解在紫外-可见光-近红外波长范围(245 纳米到 2500 纳米)内,异价铁取代如何影响主 YSZ 和 ZrO2 系统的光学吸收光谱。在铁取代的 ZrO2 体系中,以单斜晶系结构合成了相纯(99% 纯度)的样品,而在 YSZ 中,铁的取代导致了四方相和单斜相共存的两相混合物。室温下进行的光学特性分析表明,这两种体系都有两条宽吸收带:一条以 1000 纳米为中心,另一条以 500 纳米为中心。对光学吸收数据的陶克图分析表明,随着铁浓度的增加,两种材料体系的光带隙都会减小。以 G0W0 和 Bethe-Salpeter 方程为基础的多体扰动理论方法被用来计算 YSZ 和 ZrO2 的四方和单斜晶体结构中作为铁替代函数的光吸收光谱模型。构建了超级晶胞,并探索了 Zr 位点中的几种 Fe 原子和/或 Y 原子构型。为了保持电中性,引入了电荷补偿 O 空位。计算结果表明,观察到的以 1000 nm 为中心的光激发可能具有缺陷态引起的激子特性,其起源可追溯到 Fe-3d 和 Fe-3d 轨道之间的电子跃迁。有趣的是,四方和单斜晶体结构似乎都支持局部多面体畸变,从而促进了 1000 纳米波长区域的激发。以 500 nm 波长为中心的激发归因于这些材料的光带隙。这项研究成果揭示了铁取代 YSZ 的辐射特性,对热障涂层成分的设计具有重要意义。
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引用次数: 0
High mobility charge transport in a multicarrier altermagnet CrSb 多载流子变磁体 CrSb 中的高迁移率电荷传输
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-08-29 DOI: 10.1103/physrevmaterials.8.084412
Takahiro Urata, Wataru Hattori, Hiroshi Ikuta
A newly identified magnetic phase called altermagnet is being actively studied because of its unprecedented spin-dependent phenomena. Among the candidate materials, CrSb has a particularly high ordering temperature and a large spin-splitting energy, but its transport properties have remained unexplored. In this study, we report the magnetotransport properties of CrSb measured on single crystals. We found that the Hall resistivity shows a nonlinear dependence on the magnetic field at low temperatures. From symmetry-based considerations, however, this behavior cannot be attributed to an anomalous Hall effect, but to a multicarrier effect. A multicarrier fitting to the in-plane conductivity tensor revealed the presence of carriers with high mobility in CrSb, which is an advantage for efficient spin current generation.
由于其前所未有的自旋依赖现象,一种新发现的磁性相--"变磁体"(altermagnet)正被积极研究。在候选材料中,CrSb 具有特别高的有序温度和较大的自旋分裂能,但其传输特性仍未得到探索。在本研究中,我们报告了在单晶体上测量到的铬锑的磁传输特性。我们发现,霍尔电阻率在低温下与磁场呈非线性依赖关系。然而,基于对称性的考虑,这种行为不能归因于异常霍尔效应,而应归因于多载波效应。对平面内电导张量进行多载流子拟合后发现,CrSb 中存在高迁移率的载流子,这是高效产生自旋电流的一个优势。
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引用次数: 0
Point defects in CdTe and CdTeSe alloy: A first principles investigation with DFT+U 碲化镉和碲化镉合金中的点缺陷:利用 DFT+U 的第一原理研究
IF 3.4 3区 材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY Pub Date : 2024-08-28 DOI: 10.1103/physrevmaterials.8.084602
Xiaofeng Xiang, Yijun Tong, Aaron Gehrke, Scott T. Dunham
CdTe and its alloy CdSeTe are widely used in optoelectronic devices, such as radiation detectors and solar cells, due to their superior electrical properties. However, the formation of defects and defect complexes in these materials can significantly affect their performance. As a result, understanding the defect formation and recombination processes in CdTe and CdSeTe alloy is of great importance. In recent years, density functional theory (DFT) calculations have emerged as a powerful tool for investigating the properties of defects in semiconductors. In this paper, we use DFT+U calculations to comprehensively study the properties of intrinsic defects as well as extrinsic defects induced by commonly used dopants, such as Cu and group V elements, in CdTe and CdSeTe alloy. This work provides insights into the effects of these defects on the electrical and optical properties of the material.
碲化镉及其合金碲化镉因其优异的电气性能而被广泛应用于光电设备,如辐射探测器和太阳能电池。然而,这些材料中缺陷和缺陷复合物的形成会严重影响其性能。因此,了解 CdTe 和 CdSeTe 合金中的缺陷形成和重组过程非常重要。近年来,密度泛函理论(DFT)计算已成为研究半导体缺陷特性的有力工具。本文利用 DFT+U 计算全面研究了 CdTe 和 CdSeTe 合金中铜和 V 族元素等常用掺杂剂诱导的本征缺陷和外征缺陷的性质。这项研究深入揭示了这些缺陷对材料电学和光学特性的影响。
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引用次数: 0
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