拓绝缘器是否有望成为热电?
Michael Y Toriyama1, G Jeffrey Snyder1
1Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA. MichaelToriyama2024@u.northwestern.edu.
Materials horizons
|January 8, 2024
概括
拓绝缘体 (TI) 在热电 (TE) 应用中表现有前途. 在TI中带逆转驱动的曲通过减少质量和增加谷变性来提高TE性能,使它们成为TE设备的强大候选者.
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
- 固态物理 固态物理
背景情况:
- 拓绝缘器 (TI) 由于其表面状态而具有独特的电子特性.
- 现有的研究通常集中在热电 (TE) 应用的TI表面状态上,忽视了散装特性.
- 目前TE设备的操作条件与TI表面状态最有效的条件有很大的不同.
研究的目的:
- 调查散带结构在拓绝缘体 (TI) 的热电性能中的作用.
- 为了确定TI是否可以在相关条件下超过正常绝缘体作为热电材料.
- 确定提高热电效率的TI的关键特性.
主要方法:
- 使用密度函数理论 (DFT) 进行高通量运输计算.
- 基于博尔兹曼运输理论的理论模型的开发.
- 分析带结构属性,特别是带反向和曲.
主要成果:
- 优化的TI通常在同一个结构类别内的正常绝缘体中表现优于正常绝缘体.
- 热电性能与频段逆转的强度正相关.
- 带逆转驱动的曲被确定为通过减少运输质量和增加谷变性来增强TE性能的机制.
结论:
- 带逆转强度是TI的热电性能的一个关键因素.
- 波段逆转的后果是曲,显著提高了TE的效率.
- 合金和应变工程被提出为调整带逆转和改善TI中的TE性能的策略,将其定位为TE应用的可行候选者.
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