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arXiv 0906.2682cond-mat.supr-concond-mat.str-el
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高Tc氧化铜超导体中费米弧和费米袋的共存

Coexistence of Fermi arcs and Fermi pockets in a high Tc copper oxide superconductor

Jianqiao Meng, Guodong Liu, Wentao Zhang, Lin Zhao, Haiyun Liu, Xiaowen Jia, Daixiang Mu, Shanyu Liu, Xiaoli Dong, Wei Lu, Guiling Wang, Yong Zhou, Yong Zhu, Xi… 展开作者

Jianqiao Meng, Guodong Liu, Wentao Zhang, Lin Zhao, Haiyun Liu, Xiaowen Jia, Daixiang Mu, Shanyu Liu, Xiaoli Dong, Wei Lu, Guiling Wang, Yong Zhou, Yong Zhu, Xiaoyang Wang, Zuyan Xu, Chuangtian Chen, X. J. Zhou

摘要:

在高Tc氧化铜(铜酸盐)超导体的赝能隙态中,角分辨光电发射(ARPES)测量已经看到费米弧,即,在大费米表面中的开放式无间隙部分,而不是普通金属所期望的闭合回路。这是所有更令人费解的,因为费米口袋(小封闭费米表面特征)已建议从最近的量子振荡测量。费米弧多年来一直困扰着高Tc社区,因为它们无法用现有的理论来理解。理论家们想出了一个办法,那就是在传统的费米表面形成与竞争秩序相关的口袋,由于详细的原因,它的背面是光电发射看不见的。在这里,我们报告ARPES测量的La-Bi 2201,费米口袋的直接证据。口袋中的载流子是空穴,口袋显示出对掺杂的不寻常的依赖性,即它们存在于欠掺杂而不是过掺杂的样品中。令人惊讶的是,这些费米口袋似乎与费米弧共存。这种共存在理论上是没有预料到的,对高Tc铜氧化物超导体中神秘的赝能隙态的理解将严重依赖于对这种新发现的理解。

英文摘要:

In the pseudogap state of the high-Tc copper-oxide (cuprate) superconductors, angle-resolved photoemission (ARPES) measurements have seen an Fermi arc, i.e., an open-ended gapless section in the large Fermi surface, rather than a closed loop expected of an ordinary metal. This is all the more puzzling because Fermi pockets (small closed Fermi surface features) have been suggested from recent quantum oscillation measurements. The Fermi arcs have worried the high-Tc community for many years because they cannot be understood in terms of existing theories. Theorists came up with a way out in the form of conventional Fermi surface pockets associated with competing order, with a back side that is for detailed reasons invisible by photoemission. Here we report ARPES measurements of La-Bi2201 that give direct evidence of the Fermi pocket. The charge carriers in the pocket are holes and the pockets show an unusual dependence upon doping, namely, they exist in underdoped but not overdoped samples. A big surprise is that these Fermi pockets appear to coexist with the Fermi arcs. This coexistence has not been expected theoretically and the understanding of the mysterious pseudogap state in the high-Tc cuprate superconductors will rely critically on understanding such a new finding.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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