新兴的超导和竞争的收费订单在孔合的方格格子t-J模型中
Physical review letters
|February 23, 2024
概括
这项研究揭示了扩展的t-J模型中的超导性 (SC),挑战了以前的发现. 改进的模拟显示,d波SC在孔化侧出现,为非传统超导体提供了新的见解.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子材料是一种量子材料.
- 强相关性 物理 物理
背景情况:
- 哈伯德和t-J模型对于理解强相关性效应和非常规超导 (SC) 是根本性的.
- 之前在扩展的t-J模型上进行的模拟显示了在电子合系统中SC,但在孔合系统中充电密度波 (CDW) 顺序与cuprate观测相冲突.
研究的目的:
- 用先进的计算方法重新检查扩展的t-J模型的基态相图.
- 解决理论预测和实验观测超导性在孔化酸盐之间的差异.
主要方法:
- 最先进的密度矩阵重规范化组 (DMRG) 计算.
- 利用显著增强的结合尺寸,以获得更高的准确性.
- 在六腿和八腿圆柱形几何体上进行的模拟.
主要成果:
- 在六脚气上,d波超导性 (SC) 出现于洞 doped 侧的较低的 doping 模式,与 CDW 阶段共存.
- 在更广泛的八脚系统上,d波SC在最佳的1/8兴奋剂中占主导地位,超过了竞争中的CDW顺序.
- 配对相关性在超导阶段表现出代数衰变和d波对称性.
结论:
- 在扩展的t-J模型中,增加系统宽度有利于超导性而不是电荷密度波序.
- 这些发现表明通过减轻竞争的充电订单来实现超导的新途径.
- 结果提供了一个统一的视角,对超导在两个洞和电子合的酸盐材料的超导.
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