Superconducting correlations in thin films of amorphous indium oxide on the insulating side of the disorder-tuned superconductor-insulator transition

摘要

We study the magnetoresistance of an amorphous indium-oxide thin film whose disorder places it in the insulating side immediately after the disorder-tuned superconductor-insulator transition. We examine the magnetic field orientation dependence of the magnetoresistance and find both a pronounced insulating peak as a function of magnetic field and anisotropic behavior at low fields followed by high isotropy at higher fields, which both characterize highly disordered superconductors. Our findings establish a clear link between its low-field insulating phase and superconductivity.