Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe2As2
Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe2As2
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FeAs 基超导体 KFe2As2 的量子临界性和节点超导性
DOI：
10.1103/physrevlett.104.087005
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发表时间：
2010-02-26
影响因子：
8.6
通讯作者：
Li, S. Y.
中科院分区：
文献类型：
--
作者：
Dong, J. K.;Zhou, S. Y.;Li, S. Y.
测量了GaAs基超导体单晶的面内磁导率和热导率，测量值低至50 mK。我们观察到非费米液体的行为，并随着进一步增加的领域费米液体的发展。这表明在超导上临界场处存在场诱导量子临界点。在零场时，存在一个大的剩余线性项，场依赖性类似于波中铜氧化物超导体。这表明超导能隙具有节点，似波对称。这种节点超导性归因于量子临界点附近的反铁磁自旋涨落。
The in-plane resistivityand thermal conductivityof the FeAs-based superconductorsingle crystal were measured down to 50 mK. We observe non-Fermi-liquid behaviorat, and the development of a Fermi liquid state withwhen further increasing the field. This suggests a field-induced quantum critical point, occurring at the superconducting upper critical field. In zero field, there is a large residual linear term, and the field dependence ofmimics that in-wave cuprate superconductors. This indicates that the superconducting gaps inhave nodes, likely-wave symmetry. Such a nodal superconductivity is attributed to the antiferromagnetic spin fluctuations near the quantum critical point.