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arXiv 0901.4826cond-mat.supr-concond-mat.str-el
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条纹超导体:铜氧化物如何干涉自旋、电荷和超导序

Striped superconductors: How the cuprates intertwine spin, charge and superconducting orders

Erez Berg, Eduardo Fradkin, Steven A. Kivelson, John Tranquada

摘要:

最近的输运实验在原来的铜氧化物高温超导体,{La $_{2-x}$ Ba $_x$ CuO $_4$ },揭示了一个显着的序列的转变和交叉引起的一种形式的动态降维,其中块体晶体成为基本超导在两个方向上,而它仍然在第三个不良的金属。我们确定这些现象所产生的一个独特的新的超导状态,“条纹超导体,”在超导秩序是空间调制,使其体积平均值为零。在这里,除了概述突出的实验发现,我们勾勒状态的序参量理论,强调条纹超导体从根本上不同于普通(均匀)超导体的一些方式,特别是关于它对猝灭随机性的反应。我们还提出了DMRG计算的结果,在相互作用的电子模型中,超导秩序的符号振荡建立。最后,我们推测这种状态的相关性,在其他铜酸盐的实验,包括最近的光学研究{La $_{2-x}$ Sr $_x$ CuO $_4$ }在磁场中,中子散射实验欠掺杂{YBa $_2$ Cu $_3$ O $_{6+x}$ },和一系列的STM和ARPES研究中看到的异常{Bi $_2$ Sr $_2$ CaCu $_2$ O $_{8+δ} $ }。

英文摘要:

Recent transport experiments in the original cuprate high temperature superconductor, {La$_{2-x}$Ba$_x$CuO$_4$}, have revealed a remarkable sequence of transitions and crossovers which give rise to a form of dynamical dimensional reduction, in which a bulk crystal becomes essentially superconducting in two directions while it remains poorly metallic in the third. We identify these phenomena as arising from a distinct new superconducting state, the "striped superconductor," in which the superconducting order is spatially modulated, so that its volume average value is zero. Here, in addition to outlining the salient experimental findings, we sketch the order parameter theory of the state, stressing some of the ways in which a striped superconductor differs fundamentally from an ordinary (uniform) superconductor, especially concerning its response to quenched randomness. We also present the results of DMRG calculations on a model of interacting electrons in which sign oscillations of the superconducting order are established. Finally, we speculate concerning the relevance of this state to experiments in other cuprates, including recent optical studies of {La$_{2-x}$Sr$_x$CuO$_4$} in a magnetic field, neutron scattering experiments in underdoped {YBa$_2$Cu$_3$O$_{6+x}$}, and a host of anomalies seen in STM and ARPES studies of {Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ} $}.

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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