Bi2 Te3 间接的MnBi2 Te4 是探索内在的切尔恩绝缘体和高温量子异常霍尔效应的理想候选者
Yaling Zhang1, Jingjing Zhang2, Wenjia Yang1
1College of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, Shanxi Normal University, Taiyuan 030006, People's Republic of China.
Journal of physics. Condensed matter : an Institute of Physics journal
|September 4, 2023
概括
将Bi2Te3层插入到MnBi2Te4磁拓绝缘体中可以诱导铁磁合,使等层系统中的量子异常霍尔效应成为可能. 这项研究指导着对这些材料中高温QAH效应的探索.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子现象是一种量子现象.
背景情况:
- MnBi2Te4 (MBT) 是一种具有量子异常霍尔效应 (QAH) 的磁拓绝缘体.
- 在MBT中,QAH效应通常仅限于奇数层系统和由于抗铁磁层间合而导致的低温.
研究的目的:
- 研究MnBi2Te4和Bi2Te3 (MBT/(BT) n/MBT) 的异构结构,以实现铁磁 (FM) 层间合.
- 探索在均层系统和潜在的更高温度下实现QAH效应的可能性.
主要方法:
- 使用第一原则计算来研究MBT/(BT) n/MBT异构结构 (n=1-6) 的电子和磁性特性.
- 使用带结构计算和拓识别来确认QAH阶段的保存.
- 使用连续模型分析来理解拓机制作为n的函数.
主要成果:
- Bi2Te3层的间隙诱导磁相从抗铁磁到铁磁合的磁相转换为n >= 3.
- MBT/(BT) 3/MBT和MBT/(BT) 4/MBT的基里温度分别为14K和11K,与实验结果一致.
- 在所有铁磁异构结构中,QAH相被保存,拓机制被阐明.
- 经过实验制造的FM MBT/(BT)4/MBT证明了这些异构结构的实际可行性.
结论:
- MBT/(BT) n/MBT异构为设计磁拓绝缘体中的铁磁介层合提供了一个可行的途径.
- 这些发现为在MnBi2Te4材料家族中发现高温QAH效应提供了实用指南.
- 这项研究为探索量身定制的异构结构中的新型量子现象铺平了道路.
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