Constrain on possible pairing symmetry in a two-orbital model of FeAs-based superconductors

TL;DR

This paper derives exact identities in a two-orbital model for FeAs-based superconductors to constrain possible pairing symmetries, proposing favorable pairing states for high-temperature oxypnictide superconductors.

Contribution

It introduces rigorous identities that restrict the pairing symmetries in a two-orbital model of FeAs-based superconductors, guiding the understanding of their pairing mechanisms.

Findings

Derived exact identities for pairing operators

Established constraints on pairing symmetries

Proposed favorable pairing states for high-temperature superconductors

Abstract

In this work, we establish a few exact identities through commutation of intra-orbital and inter-orbital on-site pairings with a two-orbital model describing newly discovered FeAs-based superconductors. Applying the conclusion drawn from rigorous relation and physical interpretation, we give constraints on the possible symmetries of the superconducting pairing of the model. Hence the favorable pairings in newly discovered high-temperature oxypnictide superconductors are proposed.