Phonon collapse and anharmonic melting of the 3D charge-density wave in kagome metals

IF 7.5 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY Communications Materials Pub Date : 2024-10-21 DOI:10.1038/s43246-024-00676-0
Martin Gutierrez-Amigo, Ðorđe Dangić, Chunyu Guo, Claudia Felser, Philip J. W. Moll, Maia G. Vergniory, Ion Errea
{"title":"Phonon collapse and anharmonic melting of the 3D charge-density wave in kagome metals","authors":"Martin Gutierrez-Amigo, Ðorđe Dangić, Chunyu Guo, Claudia Felser, Philip J. W. Moll, Maia G. Vergniory, Ion Errea","doi":"10.1038/s43246-024-00676-0","DOIUrl":null,"url":null,"abstract":"The charge-density wave (CDW) mechanism and resulting structure of the AV3Sb5 family of kagome metals has posed a puzzling challenge since their discovery four years ago. In fact, the lack of consensus on the origin and structure of the CDW hinders the understanding of the emerging phenomena. Here, by employing a non-perturbative treatment of anharmonicity from first-principles calculations, we reveal that the charge-density transition in CsV3Sb5 is driven by the large electron-phonon coupling of the material and that the melting of the CDW state is attributed to ionic entropy and lattice anharmonicity. The calculated transition temperature is in very good agreement with experiments, implying that soft mode physics are at the core of the charge-density wave transition. Contrary to the standard assumption associated with a pure kagome lattice, the CDW is essentially three-dimensional as it is triggered by an unstable phonon at the L point. The absence of involvement of phonons at the M point enables us to constrain the resulting symmetries to six possible space groups. The unusually large electron-phonon linewidth of the soft mode explains why inelastic scattering experiments did not observe any softened phonon. We foresee that large anharmonic effects are ubiquitous and could be fundamental to understand the observed phenomena also in other kagome families. The charge-density wave state in AV3Sb5 kagome metals is intimately related to several unconventional and intriguing phenomena, but its origin and structure are still under debate. Here, non-perturbative calculations indicate a large electron-phonon coupling as the driving mechanism, attributing the melting of the charge-density wave state to ionic entropy and lattice anharmonicity.","PeriodicalId":10589,"journal":{"name":"Communications Materials","volume":null,"pages":null},"PeriodicalIF":7.5000,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s43246-024-00676-0.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Communications Materials","FirstCategoryId":"1085","ListUrlMain":"https://www.nature.com/articles/s43246-024-00676-0","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0

Abstract

The charge-density wave (CDW) mechanism and resulting structure of the AV3Sb5 family of kagome metals has posed a puzzling challenge since their discovery four years ago. In fact, the lack of consensus on the origin and structure of the CDW hinders the understanding of the emerging phenomena. Here, by employing a non-perturbative treatment of anharmonicity from first-principles calculations, we reveal that the charge-density transition in CsV3Sb5 is driven by the large electron-phonon coupling of the material and that the melting of the CDW state is attributed to ionic entropy and lattice anharmonicity. The calculated transition temperature is in very good agreement with experiments, implying that soft mode physics are at the core of the charge-density wave transition. Contrary to the standard assumption associated with a pure kagome lattice, the CDW is essentially three-dimensional as it is triggered by an unstable phonon at the L point. The absence of involvement of phonons at the M point enables us to constrain the resulting symmetries to six possible space groups. The unusually large electron-phonon linewidth of the soft mode explains why inelastic scattering experiments did not observe any softened phonon. We foresee that large anharmonic effects are ubiquitous and could be fundamental to understand the observed phenomena also in other kagome families. The charge-density wave state in AV3Sb5 kagome metals is intimately related to several unconventional and intriguing phenomena, but its origin and structure are still under debate. Here, non-perturbative calculations indicate a large electron-phonon coupling as the driving mechanism, attributing the melting of the charge-density wave state to ionic entropy and lattice anharmonicity.

Abstract Image

查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
神户金属中三维电荷密度波的声子塌缩和非谐波熔化
自四年前发现 AV3Sb5 卡戈米金属家族以来,其电荷密度波(CDW)机制和由此产生的结构一直是一个令人费解的难题。事实上,对电荷密度波的起源和结构缺乏共识阻碍了人们对这一新现象的理解。在这里,我们利用第一原理计算中的非微扰处理非谐波性,揭示了 CsV3Sb5 中的电荷密度转变是由材料的大电子-声子耦合驱动的,而 CDW 状态的熔化则归因于离子熵和晶格非谐波性。计算得出的转变温度与实验结果非常吻合,这意味着软模式物理是电荷密度波转变的核心。与纯卡格姆晶格的标准假设相反,电荷密度波本质上是三维的,因为它是由 L 点的不稳定声子引发的。由于 M 点没有声子的参与,我们得以将由此产生的对称性限制在六个可能的空间群内。软模式异常巨大的电子-声子线宽解释了为什么非弹性散射实验没有观察到任何软化声子。我们预见到大的非谐波效应无处不在,而且可能是理解其他神户系中所观察到的现象的基础。AV3Sb5 kagome 金属中的电荷密度波态与几种非常规和有趣的现象密切相关,但其起源和结构仍存在争议。在这里,非微扰计算表明电子-声子耦合是驱动机制,电荷密度波态的熔化归因于离子熵和晶格非谐性。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 去求助
来源期刊
Communications Materials
Communications Materials MATERIALS SCIENCE, MULTIDISCIPLINARY-
CiteScore
12.10
自引率
1.30%
发文量
85
审稿时长
17 weeks
期刊介绍: Communications Materials, a selective open access journal within Nature Portfolio, is dedicated to publishing top-tier research, reviews, and commentary across all facets of materials science. The journal showcases significant advancements in specialized research areas, encompassing both fundamental and applied studies. Serving as an open access option for materials sciences, Communications Materials applies less stringent criteria for impact and significance compared to Nature-branded journals, including Nature Communications.
期刊最新文献
Unraveling the origin of conductivity change in Co-doped FeRh phase transition Author Correction: Electrical response and biodegradation of Sepia melanin-shellac films printed on paper Thermodynamic evidence for polaron stabilization inside the antiferromagnetic order of Eu5In2Sb6 Benefits and complexity of defects in metal-organic frameworks Multi-sensing yarns for continuous wireless sweat lactate monitoring
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1