Spin triplet superconductivity in Sr2RuO4
Spin triplet superconductivity in Sr2RuO4
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Sr2RuO4 中的自旋三重态超导
DOI：
10.1002/pssb.200301672
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
Balazs L. Gyorffy
中科院分区：
文献类型：
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作者：
K. Wysokiński;Grzegorz Litak;J. F. Annett;Balazs L. Gyorffy
目前，Sr2RuO4是3He中三重态超流的超导模拟的最佳候选者。这种材料在正常状态下是良好的(尽管相关的)费米液体，在T_c以下是一种奇特的超导体。超导机制和有序参数的对称性是目前研究的主要困惑问题。在这里，我们给出了我们对本材料中实现的超导状态的可行描述的搜索结果。我们的计算是基于一个具有真实能带结构的三维有效三带模型。我们在费米面的三个薄片上都发现了一个非零序参数的态。准粒子谱中对应的带隙在α和β片上有线或点节点，在γ片上是复杂的，没有节点。这一状态很好地描述了现有的一些实验，包括比热的功率低温依赖关系、穿透深度、热导率等，并简要分析了状态相对于无序和不同相互作用参数的稳定性。
Sr2RuO4 is at present the best candidate for being a superconducting analogue of the triplet superfluidity in 3He. This material is a good (albeit correlated) Fermi liquid in the normal state and an exotic superconductor below Tc. The mechanism of superconductivity and symmetry of the order parameter are the main puzzling issues of on‐going research. Here we present the results of our search for a viable description of the superconducting state realised in this material. Our calculations are based on a three‐dimensional effective three‐band model with a realistic band structure. We have found a state with non‐zero order parameter on each of the three sheets of the Fermi surface. The corresponding gap in the quasi‐particle spectrum has line or point nodes on the α and β sheets and is complex with no nodes on the γ sheet. This state describes remarkably well a number of existing experiments including power low temperature dependence of the specific heat, penetration depth, thermal conductivity etc. The stability of the state with respect to disorder and different interaction parameters are also analyzed briefly.