Orbitronics effects in spin-singlet superconductors

Abstract

We consider the role of crystalline symmetries to yield Cooper pairs with non-trivial orbital moment. To this aim, we focus on two-dimensional multi-orbital spin-singlet superconductors and introduce interactions that can break the mirrors and rotation symmetries. The low degree of spatial symmetry content is able to generate Cooper pairs with high-orbital moment that are marked by distinct phase texture in the momentum space. We show how the corresponding superconducting phase pattern depends on the orientation of the orbital moment of the Cooper pairs and on the amplitude of its projection. In doing that we determine the evolution of the superconducting order parameters by self-consistent approach and explicitly present the profile of the superconducting phase in momentum space in terms of the crystalline symmetry breaking couplings. These findings can be relevant for the design of superconducting inteferometric devices that are fully rooted on the phase pattern of the orbitally polarized Cooper pairs.