论文标题
在Tase $ _3 $的单层中金属和半导体状态之间竞争的应变控制
Strain control of the competition between metallic and semiconducting states in single-layers of TaSe$_3$
论文作者
论文摘要
tase $ _3 $是一种金属分层材料，其结构是由tase $ _3 $三角形棱镜链构建的。在这项工作中，我们报告了Tase $ _3 $单层的第一原理密度功能理论研究，我们发现，尽管存在不可忽略的SE ... Se Interlayer相互作用，但仍发现Tase $ _3 $单层是金属的。但是，在应变的效果下发现了金属和半导体状态之间的有趣竞争。尽管孔载体的性质发生变化，但单层在双轴应变下保持金属行为。相反，沿链方向的单轴应变会诱导半导体状态的稳定。沿层的长（链间）轴，在双轴应变或单轴应变下发现了由于费米表面筑巢引起的潜在电子不稳定性。还考虑了双层和三角形。分析了这些意外观察的背后的结构和电子特征。
TaSe$_3$ is a metallic layered material whose structure is built from TaSe$_3$ trigonal prismatic chains. In this work we report a first-principles density functional theory study of TaSe$_3$ single-layers and we find that, despite the existence of non negligible Se...Se interlayer interactions, TaSe$_3$ single layers are found to be metallic. However, an interesting competition between metallic and semiconducting states is found under the effect of strain. The single-layers keep the metallic behaviour under biaxial strain although the nature of the hole carriers changes. In contrast, uniaxial strain along the chains direction induces the stabilization of a semiconducting state. Potential electronic instabilities due to Fermi surface nesting are found for single-layers under either biaxial strain or uniaxial strain along the long (inter-chain) axis of the layers. Bilayers and trilayers have also been considered. The structural and electronic features behind these unexpected observations are analyzed.
