在一个不对称的铁电In2Te2S单层中对拓相变的非挥发性控制
Guang Song1, Yangyang Wu1, Lei Cao1
1Department of Physics, Huaiyin Institute of Technology, Huaian 223003, China. gsong@hyit.edu.cn.
Physical chemistry chemical physics : PCCP
|September 5, 2023
概括
研究人员在铁电单层中创建了一个Janus结构,打破对称性以达到不同的金属和半导体状态. 这一突破使先进的多功能设备能够对拓电子状态进行非挥发性控制.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 合拓电子状态和铁电对于多功能设备至关重要.
- 在单个铁电 (FE) 单层中实现这一点是具有挑战性的,因为拓学上相当的极化状态.
研究的目的:
- 通过创建一个Janus结构来打破FE单层中极化状态的对称性.
- 在单相系统中设计拓顺序的非挥发性铁电控制.
主要方法:
- 使用第一原则计算来研究In2Te2S单层,这是从In2Te3.3衍生的Janus结构.
- 包括旋转轨道合来分析电子带结构和拓性质.
主要成果:
- In2Te2S单层表现出两个不对称的极化状态:一种是金属的,一种是半导体的.
- 包括旋转轨道合在金属状态中打开了50.4 meV的带隙,诱导了一个非微不足道的拓阶段.
- 拓相变与因电荷转移而减弱的内在电场有关.
结论:
- 在FE单层中构建Janus结构是一个可行的策略,可以实现不对称的极化状态.
- 这种方法可以设计用于非挥发性多功能设备的新型不对称FE材料.
- 这些发现为通过铁电工程控制拓秩序提供了洞察力.
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