电子化酸中的伪间隙:强烈的相关性导致带分裂
Masafumi Horio1,2, Shiro Sakai3, Hakuto Suzuki1,4
1Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
概括
酸盐超导体中的伪间隙在展开的费米表面上打开,而不是反铁磁布里卢恩区域边界. 这一发现,在电子合酸盐中观察到,挑战了现有的理论,并为高温超导提供了新的见解.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子材料是一种量子材料.
背景情况:
- 酸盐高温超导体中的伪间隙现象仍然是一个重大的.
- 之前的理论将电子合酸盐中的伪间隙归因于由反铁磁 (AFM) 秩序引起的带折叠.
研究的目的:
- 为了调查电子兴奋剂酸盐中的伪间隙的起源.
- 为了澄清伪间隙,反铁磁和超导之间的关系.
主要方法:
- 在Pr$_{1.3-x}$La$_{x}$Ce$_{y}$CuO$_{4}$ (x=0.7,y=0.15) 上进行了角度分辨光辐射光谱学 (ARPES).
- 测量过程中使用了精细的动量切割来精确确定差距开口的位置.
- 集群动态平均场理论 (CDMFT) 的计算被用来建模电子相关性.
主要成果:
- 发现伪间隙在未折叠的费米表面上打开,而不是AFM Brillouin区域边界.
- 间隙呈现出完全的Brillouin区域对称性,没有节点.
- 差距大小从区域对角向 ($ extit{π}$,0) 方向下降,与孔合的铜板相反.
- 通过CDMFT计算成功复制了实验结果.
结论:
- 电子合酸盐中的伪间隙源于在未折叠的费米表面上打开一个间隙.
- 这支持一种机制,其中合Mott绝缘体会产生由伪间隙分离的内隙带.
- 这些发现为理解高温超导提供了关键的实验和理论证据.
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