Broken rotational symmetry on the Fermi surface of a high-Tc superconductor
Broken rotational symmetry on the Fermi surface of a high-Tc superconductor
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DOI：
10.1038/s41535-017-0013-z
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发表时间：
2017-02
影响因子：
5.7
通讯作者：
B. Ramshaw;B. Ramshaw;N. Harrison;S. Sebastian;S. Ghannadzadeh;S. Ghannadzadeh;K. Modic;D. Bonn;W. Hardy;R. Liang;P. Goddard
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文献类型：
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作者：
B. Ramshaw;B. Ramshaw;N. Harrison;S. Sebastian;S. Ghannadzadeh;S. Ghannadzadeh;K. Modic;D. Bonn;W. Hardy;R. Liang;P. Goddard
在几种非常规超导体的实验性质中观察到四重旋转（C4）对称性的破缺。有人提出，这种对称性破缺对这些材料中的超导配对很重要，但在高铜酸盐中，这种对称性破缺从未在费米表面上被观察到。本文报道了欠掺杂高转变温度（high- tc）超导体YBa2Cu3O6.58层间磁电阻的角度依赖性的明显各向异性，直接揭示了费米表面c4对称性的破坏。此外，我们证明了这种费米表面具有由单轴或各向异性密度波相位产生的c2对称性。这确立了c4对称性破缺在YBa2Cu3O6+δ的费米表面重建中的核心作用，并表明在非常规超导体中具有惊人的普遍性。
Broken fourfold rotational (C4) symmetry is observed in the experimental properties of several classes of unconventional superconductors. It has been proposed that this symmetry breaking is important for superconducting pairing in these materials, but in the high-Tccuprates this broken symmetry has never been observed on the Fermi surface. Here we report a pronounced anisotropy in the angle dependence of the interlayer magnetoresistance of the underdoped high transition temperature (high-Tc) superconductor YBa2Cu3O6.58, directly revealing broken C4symmetry on the Fermi surface. Moreover, we demonstrate that this Fermi surface has C2symmetry of the type produced by a uniaxial or anisotropic density-wave phase. This establishes the central role of C4symmetry breaking in the Fermi surface reconstruction of YBa2Cu3O6+δ, and suggests a striking degree of universality among unconventional superconductors.