Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854, USA.
Department of Physics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom.
Phys Rev Lett. 2023 Mar 31;130(13):136002. doi: 10.1103/PhysRevLett.130.136002.
Observing that several U and Ce based candidate triplet superconductors share a common structural motif, with pairs of magnetic atoms separated by an inversion center, we hypothesize a triplet pairing mechanism based on an interplay of Hund's and Kondo interactions that is unique to this structure. In the presence of Hund's interactions, valence fluctuations generate a triplet superexchange between electrons and local moments. The offset from the center of symmetry allows spin-triplet pairs formed by the resulting Kondo effect to delocalize onto the Fermi surface, precipitating superconductivity. We demonstrate this mechanism within a minimal two-channel Kondo lattice model and present support for this pairing mechanism from existing experiments.
观察到几个基于 U 和 Ce 的候选三重超导材料具有共同的结构特征，即磁原子对被反演中心隔开，我们假设了一种基于 Hund 相互作用和 Kondo 相互作用相互作用的三重配对机制，这种机制是这种结构所特有的。在 Hund 相互作用的存在下，价态涨落会导致电子和局域磁矩之间产生三重超交换。这种对称性中心的偏移使得由 Kondo 效应产生的自旋三重态对能够局域到费米面，从而引发超导性。我们在一个最小的双通道 Kondo 晶格模型中证明了这种机制，并从现有的实验中为这种配对机制提供了支持。
