物理学报Issue(10)：1-9,9.DOI:10.7498/aps.64.107301
单轴压力下Ge2X2Te5（X =Sb，Bi）薄膜拓扑相变的第一性原理研究∗
First-principles study on the uniaxial pressure induced topological quantum phase transitions of Ge2X2Te5 (X =Sb, Bi) thin films
摘要
Abstract
Since the topological insulator was discovered, the investigation of topological properties has become the hot spot in condensed matter physics. In this paper, we study topological properties of chalcogenide compounds Ge2X2Te5 (X =Sb, Bi) crystals and their monolayer and bilayer films as well as the vertical uniaxial pressure induced topological quantum phase transitions in monolayer and bilayer films. The results show that for A-type crystal, the bulk structures of these two compounds are topological insulators, the monolayer structures of these two compounds are conventional metals, and bilayer structures are topological metals. There is no topological quantum phase transition in monolayer nor bilayer film under the uniaxial compression. While for B-type crystal, the bulk structures of these two compounds are conventional insulators, the monolayer Ge2Sb2Te5 is conventional metal, its bilayer structure as well as monolayer and bilayer of Ge2Bi2Te5 films is conventional insulator. All the B-type monolayer and bilayer films each undergo a topological quantum phase transition to the topological metals under the uniaxial compression.关键词
单轴压力/拓扑金属/拓扑量子相变Key words
uniaxial pressure/topological metal/topological quantum phase transition引用本文复制引用
张梅,黎巍,丁俊,张英..单轴压力下Ge2X2Te5（X =Sb，Bi）薄膜拓扑相变的第一性原理研究∗[J].物理学报,2015,(10):1-9,9.基金项目
国家自然科学基金(批准号:11135001)、国家自然科学基金专项基金(批准号:11347187)和河南省科技攻关计划(批准号:132102210141)资助的课题.* Project supported by the National Natural Science Foundation of China (Grant No.11135001), the Special Funds of the National Natural Science Foundation of China (Grant No.11347187), and the Key Science and Technology Program of Henan Province, China (Grant No.132102210141) （批准号:11135001）
