没有准颗粒的合Mott绝缘体中的Wiedemann-Franz定律
Wen O Wang1,2, Jixun K Ding1,2, Yoni Schattner2,3,4
1Department of Applied Physics, Stanford University, Stanford, CA 94305, USA.
概括
量子材料表现出不寻常的传输特性. 我们的研究揭示了低温传输在杂的Mott绝缘体接近Wiedemann-Franz法则, 提供超越传统理论的见解.
科学领域:
- 凝聚物质物理学
- 量子材料科学
背景情况:
- 许多金属量子材料显示异常运输,偏离费米液体理论.
- 了解这些现象对于开发新的电子设备至关重要.
研究的目的:
- 调查热和充电运输中使用的哈巴德模型.
- 分析量子材料中高温和低温行为之间的交叉.
主要方法:
- 热和电荷传输的数值计算.
- 洛伦兹数 (L) 和其兴奋剂依赖性的分析.
- 能量电流演员的分解.
主要成果:
- 观察到高温和低温行为之间的交叉.
- 在低温下,洛伦兹数 (L) 变得微弱依赖于兴奋剂,并接近维德曼-弗朗茨常数 (L0).
- 这种行为甚至存在于缺乏明确准粒子的合Mott绝缘体中.
结论:
- 这项研究阐明了金属的强相关性传输机制.
- 这些发现表明动力和潜在能量对电流的贡献之间的补偿.
- 这项工作为解释波尔茨曼理论之外的运输实验提供了一个框架.
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