A mechanism for mixed parity heavy fermion superconductor CeRh₂As₂.

The newly discovered heavy fermion superconductor CeRh₂As₂, is an intriguing material with a rich phase diagram including multiple superconducting phases of mixed even and odd parity states [1]. The odd pairing state emerges in the presence of applied field and survives up to 14 T. Interestingly, CeRh₂As₂ is a candidate of a class of heavy fermion superconductors which share a common structural motif where the centre of inversion is no longer at the atomic sites [2]. This locally broken inversion enables effects of spin orbit coupling (SOC) which leads to the pairing gap function to have equal or opposite signs on alternating layers. In this work we will present a minimal model which combines the pairing and the local moment moment physics of CeRh₂As₂.