An extensive impurity-scattering study on the pairing symmetry of monolayer FeSe films on SrTiO3

TL;DR

This study systematically investigates how various point defects affect electronic states in monolayer FeSe films on SrTiO3 to determine the pairing symmetry, crucial for understanding its high-temperature superconductivity.

Contribution

It provides new insights into the pairing symmetry of monolayer FeSe by analyzing impurity-induced states from different defect types using scanning tunneling spectroscopy.

Findings

Defects induce distinct electronic states revealing pairing symmetry characteristics.

Impurity scattering varies with defect type, affecting superconducting properties.

Results suggest specific pairing symmetry consistent with observed impurity effects.

Abstract

Determination of the pairing symmetry in monolayer FeSe films on SrTiO3 is a requisite for understanding the high superconducting transition temperature in this system, which has attracted intense theoretical and experimental studies but remains controversial. Here, by introducing several types of point defects in FeSe monolayer films, we conduct a systematic investigation on the impurity-induced electronic states by spatially resolved scanning tunneling spectroscopy. Ranging from surface adsorption, chemical substitution to intrinsic structural modification, these defects generate a variety of scattering strength, which renders new insights on the pairing symmetry.