# Possible pairing symmetry in the FeSe-based superconductors determined by quasiparticle interference

## TL;DR

This paper investigates the pairing symmetry in FeSe-based superconductors using quasiparticle interference, proposing that experimental data can be explained without sign-changing order parameters when incipient bands are considered.

## Contribution

It introduces an alternative interpretation of QPI data suggesting non-sign-changing pairing symmetry, emphasizing the role of incipient bands in FeSe superconductors.

## Key findings

- QPI data can be fitted without sign-changing order parameters.
- Incipient bands influence the interpretation of pairing symmetry.
- Alternative explanation challenges previous assumptions about pairing mechanisms.

## Abstract

We study the momentum-integrated quasiparticle interference (QPI) in the FeSe-based superconductors. This method was recently proposed theoretically and has been applied to determine the pairing symmetry in these materials experimentally. Our findings suggest that, if the incipient bands and the superconducting (SC) pairing on them are taken into consideration, then the experimentally measured bound states and momentum-integrated QPI can be well fitted, even if the SC order parameter does not change sign on the Fermi surfaces. Therefore, we offer an alternative explanation to the experimental data, calling for more careful identification of the pairing symmetry that is important for the pairing mechanism.