Emergent honeycomb network of topological excitations in correlated charge density wave
Emergent honeycomb network of topological excitations in correlated charge density wave
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DOI：
10.1038/s41467-019-11981-5
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发表时间：
2019-09-06
影响因子：
16.6
通讯作者：
Yeom, Han Woong
中科院分区：
文献类型：
--
作者：
Park, Jae Whan;Cho, Gil Young;Yeom, Han Woong
当两个周期电位在材料中竞争时，其中一个可能采用另一个，这直接产生拓扑缺陷。特别感兴趣的是电荷、偶极子和自旋有序系统中的畴壁，它们控制着宏观性质和重要的功能。然而，畴壁的详细原子和电子结构往往是不确定的，其功能的微观机制一直难以捉摸。本文阐明了1T-TaS2的Mott电荷密度波（CDW）相中由Z(3)涡旋连接的蜂窝状畴壁网络的完整原子和电子结构。扫描隧道显微镜分析了畴壁及其涡流内的特征电荷顺序。密度泛函理论计算揭示了它们独特的原子弛豫和被紧密限制在其中的金属隙内态。建立了一个通用理论，将这种新兴的蜂窝状导电电子网络与增强的超导性联系起来。
When two periodic potentials compete in materials, one may adopt the other, which straightforwardly generates topological defects. Of particular interest are domain walls in charge-, dipole-, and spin-ordered systems, which govern macroscopic properties and important functionality. However, detailed atomic and electronic structures of domain walls have often been uncertain and the microscopic mechanism of their functionality has been elusive. Here, we clarify the complete atomic and electronic structures of the domain wall network, a honeycomb network connected by Z(3) vortices, in the nearly commensurate Mott charge-density wave (CDW) phase of 1T-TaS2. Scanning tunneling microscopy resolves characteristic charge orders within domain walls and their vortices. Density functional theory calculations disclose their unique atomic relaxations and the metallic in-gap states confined tightly therein. A generic theory is constructed, which connects this emergent honeycomb network of conducting electrons to the enhanced superconductivity.