Microscopic theory of pairing mechanisms

Abstract

This chapter deals with the microscopic theory of pairing mechanisms for noncentrosymmetric superconductors. One of curious questions is how to understand microscopically the parity mixing arising from the interplay between pairing interactions and the spin-orbit interactions that stem from broken inversion symmetry. Here, some examples of microscopic models which exhibit this phenomenon are presented. Our argument is mainly concentrated on the heavy fermion superconductors CePt 3Si and CeRh(Ir)Si 3, for which ample experimental evidence confirms the realization of unconventional superconducticvity caused by non-phonon mechanisms. In these heavy fermion systems, superconductivity appears in or in the vicinity of an antiferromagnetic phase. Thus, it is important to clarify the role of magnetism in the pairing state. We examine the scenario that magnetic interaction is the origin of the pairing interaction for these systems. The influences of the coexisting magnetic order are also investigated. © Springer-Verlag Berlin Heidelberg 2012.