d+id'-wave Superconducting States in Graphene

TL;DR

This paper investigates the emergence of mixed pairing superconducting states in graphene, revealing a complex interplay of d-wave, s-wave, and p+ip components that influence the superconducting gap and conductance properties.

Contribution

It demonstrates that a d+id'-wave superconducting state in graphene can exhibit mixed pairing orders, including s-wave and p+ip components, at low energy.

Findings

Effective superconducting states in graphene can include mixed pairing symmetries.

The d+id'-wave state exhibits distinctive gap functions.

Unique Andreev conductance spectra are observed.

Abstract

We show that effective superconducting orders generally emerge at low energy in the superconducting state of graphene with conventionally defined pairing symmetry . We study such a particular interesting example, the $d_{x^2-y^2}+id'_{xy}$ spin singlet pairing superconducting state in graphene, which can be generated by electronic correlation as well as induced through a proximity effect with a d-wave superconductor. We find that effectively the d-wave state is a state with mixed s-wave and exotic $p+ip$-wave pairing orders at low energy. This remarkable property leads to distinctive superconducting gap functions and novel behavior of the Andreev conductance spectra.