Rashba spin-orbit coupling effects in quasiparticle interference of non-centrosymmetric superconductors
Max-Planck Institute for the Chemical Physics of Solids - D-01187 Dresden, Germany, EU
Received: 17 April 2013
Accepted: 23 May 2013
The theory of quasiparticle interference (QPI) for non-centrosymmetric (NCS) superconductors with Rashba spin-orbit coupling is developed using the T-matrix theory in Born approximation. We show that qualitatively new effects in the QPI pattern originate from the Rashba spin-orbit coupling: The resulting spin coherence factors lead to a distinct difference of charge-and spin-QPI and to an induced spin anisotropy in the latter even for isotropic magnetic impurity scattering. In particular a cross-QPI appears describing the spin oscillation pattern due to non-magnetic impurity scattering which is directly related to the Rashba vector. We apply our theory to a 2D model for the NCS heavy fermion unconventional superconductor CePt3Si and discuss the new QPI features for a gap model with accidental node lines due to its composite singlet-triplet nature.
PACS: 74.20.Rp – Pairing symmetries (other than s-wave) / 74.55.+v – Tunneling phenomena: single particle tunneling and STM / 74.70.Tx – Heavy-fermion superconductors
© EPLA, 2013