压力工程的热物理性能从带隔热到拓隔热相在β-antimonene中
Sumit Kukreti1, Surbhi Ramawat1, Nirpendra Singh2
1Advanced Materials and Device (A-MAD) Laboratory, Department of Physics, Indian Institute of Technology Jodhpur, 342030, India. ambesh@iitj.ac.in.
Nanoscale
|July 17, 2023
概括
2D β-Sb单层的应变工程诱导了拓绝缘阶段. 这一阶段表现出独特的电子,热和振动特性,为新型材料功能提供了洞察力.
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
- 纳米科学是一个纳米科学.
背景情况:
- 原子薄的二维材料具有独特的特性,可以通过应变工程来利用.
- 半导体的特性可以通过施加应变来广泛修改.
研究的目的:
- 研究压力下的β-Sb单层的结构,电子,热和振动特性.
- 在零应变时实现带绝缘阶段,在~15%双轴应变时实现拓绝缘阶段.
- 了解拓阶段开始的微观起源和应变工程结构-属性相关性.
主要方法:
- 使用第一原则计算来研究β-Sb单层.
- 分析包括结构性,电子性,热性和振动性.
- 研究了声和载体动态,以了解应变效应.
主要成果:
- 在15%的应变下观察到硬度和晶格导热率 (κl) 从4.5到3.1W m-1 K-1减少.
- 螺旋边缘状态和Z2不变证实了在15%的压力下非微不足道的拓状态.
- 外平面振动模式对拓阶段做出了显著的贡献,原因是曲高度降低.
结论:
- 在β-Sb单层中压力工程可以诱导具有不同性质的拓绝缘相.
- 在应变下键的削弱会导致不和性和热导率的降低.
- 该研究提供了关于应变,结构和2D材料中拓相的出现之间的关系的见解.
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