在非赫密斯式的米模型中异常抽
Abhishek Kumar1, Sarbajit Mazumdar2, S D Mahanti3
1Department of Physics, University of Massachusetts Amherst, Amherst, MA 01003, USA, Amherst, Massachusetts, 01003, UNITED STATES.
概括
在米模型中,具有非密度的拓性电荷送表现出新的行为,包括异常送和诱导电荷转移的微不足道协议. 这源于非赫米特系统中独特的点间隔物理学.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 拓学材料 拓学材料
- 非赫尔密斯系的系统
背景情况:
- 拓式电荷送 (TCP) 描述了由参数变化驱动的间隙系统中的电荷传输.
- 非赫米特系统引入了皮肤效应和特殊点等现象,改变了拓性质.
- 莱斯-梅尔 (RM) 模型是一个展示拓过渡的1D格子模型.
研究的目的:
- 调查米模型中的拓电荷送,具有非互惠的跳跃和非密性.
- 探索非隐居性对拓过渡和现象的影响.
- 在非赫米斯拓模型中描述新的抽行为及其潜在机制.
主要方法:
- 使用有限大小的概括Brillouin区域 (GBZ) 方案来区分边缘模式和皮肤模式.
- 分析了由非赫密斯参数gamma和系统大小N驱动的拓过渡.
- 为1+1D米模型重构了一个非Bloch拓不变量.
主要成果:
- 确定了gamma和N作为静态1D RM模型中拓过渡的独立调旋.
- 证明了标准的拓抽能够在有限的非密度下存活,但可以通过驱动协议进行修改.
- 由于非赫米斯点间物理学的原因,观察到异常的送和从微不足道的协议送.
结论:
- 非赫密性从根本上改变了拓电荷送,导致了赫密系统中不存在的现象.
- 概括的布里卢恩区域方案和非布洛克拓不变提供了强大的工具来分析非赫米特拓系统.
- 这项研究提供了对工程新拓状态和非赫米特材料中的运输现象的见解.
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