在α-T3网格中的Nernst和Seebeck效应
Ai Yan1, Xing Wang1, Yu-Xian Li1
1College of Physics and Hebei Advanced Thin Films Laboratory, Hebei Normal University, Shijiazhuang, Hebei 050024, People's Republic of China.
概括
本研究探讨了α-T3网格中的Seebeck和Nernst效应,揭示了α参数的变化如何影响热电性质和带结构,特别是在带间隙附近.
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
- 固态物理 固态物理
背景情况:
- α-T3格子是一个可调节的系统,在石墨烯和子格子之间进行插曲.
- 了解热电传输现象,如Seebeck和Nernst效应,对于能源应用至关重要.
- 之前的研究已经在石墨烯和子格子中分别探索了这些效应.
研究的目的:
- 在α-T3网格中研究Seebeck和Nernst效应,作为参数α的函数.
- 分析磁场对这些热电系数的影响.
- 探索格子边界 (旋和扶手椅) 对观察到的效应的作用.
主要方法:
- 利用紧密结合的哈密尔顿方法来建模电子带结构.
- 使用非平衡格林函数 (NEGF) 计算运输系数的方法.
- 研究了带有和没有应用磁场的系统.
主要成果:
- 对于α=0 (石墨烯),Seebeck和Nernst系数与已知的石墨烯行为相匹配,具有平面带.
- 不为零的α引入了一个奇异的西贝克系数对费米能量的依赖,在曲边界的带间隙中创建了一个大的峰值.
- 磁场增强了Seebeck系数峰值,随着α的增加. 纳恩斯特系数的零点峰值高度随着α的增加而增加,最终分裂,对齐克扎克和扶手椅边界有不同的行为.
结论:
- α-T3网格通过参数α提供可调节的热电特性.
- 边界效应对Seebeck和Nernst系数产生重大影响,特别是在带隙区域.
- 观察到的现象凸显了α-T3网格在先进的热电器件中的潜力.
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