Influence of disorder on superconductivity in the Si(111)-7×3-In surface

Abstract

To uncover the critical effect of disorder on superconductivity, the ideal method is to visualize the microscopic crystalline deficiencies in real space while measuring the macroscopic superconducting properties. By using a self-developed multifunctional scanning tunneling microscope, we investigated the correlation between controllably introduced disorder and superconductivity in the Si(111)-7×3-In surface reconstruction. It is revealed that not only the density but also the spatial distribution of surface vacancies makes a significant influence on the diamagnetic response of the superconducting surface reconstruction. The higher density of vacancies uniformly dispersed on terraces results in a lower critical temperature and critical magnetic field, while the presence of grooves formed by aggregation of vacancies at step edges reduces the critical supercurrent and thus weakens the diamagnetic shielding effect remarkably.