Off-site repulsion-induced triplet superconductivity: a possibility for chiral p(x+y)-wave pairing in Sr2RuO4.
Off-site repulsion-induced triplet superconductivity: a possibility for chiral p(x+y)-wave pairing in Sr2RuO4.
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DOI：
10.1103/physrevlett.92.247006
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发表时间：
2004-04
影响因子：
8.6
通讯作者：
R. Arita;S. Onari;K. Kuroki;H. Aoki
中科院分区：
文献类型：
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作者：
R. Arita;S. Onari;K. Kuroki;H. Aoki
为了探讨电荷涨落对三重态配对的影响，我们研究了具有离位库仑排斥（V）在在位排斥之上的单带Hubbard模型中的配对对称性，并将其作为三重态配对超导体Sr_2RuO_4的γ带模型.用动力学集团近似和量子MonteCarlo方法得到的结果与涨落交换近似得到的结果相吻合，表明当没有V时，d（x（2）-y（2））对占主导地位，而V的引入使p（x+y）和d（xy）对占主导地位.手征p（x+y）+ip（x-y）的差距函数具有与最近在双齿酸盐中旋转磁场中比热测量一致的节点。这表明离位排斥在该材料的三重态超导电性中起着重要的作用。
In order to probe the effect of charge fluctuations on triplet pairing, we study the pairing symmetry in the one-band Hubbard model having the off-site Coulomb repulsion (V) on top of the on-site repulsion as a model for the gamma band of Sr2RuO4, a strong candidate for a triplet pairing superconductor. The result, obtained with the dynamical cluster approximation combined with the quantum Monte Carlo method, and confirmed from the fluctuation exchange approximation, shows that while d(x(2)-y(2)) pairing dominates over p in the absence of V, introduction of V makes p(x+y) and d(xy) dominant. The gap function for the chiral p(x+y)+ip(x-y) has nodes that are consistent with the recent measurement of specific heat in rotated magnetic fields in the ruthenate. This suggests that the off-site repulsion may play an essential role in triplet superconductivity in this material.