On the possibility of explaining the high rate of flux creep at ultra-low temperatures using the Anderson model

Abstract

The nonvanishing magnetic relaxation rate and noticeable resistance in the resistive measurements in high-temperature superconductors (HTSCs) at ultra-low temperatures, which have recently been discussed as evidence of the quantum tunneling of vortices, is argued to be caused by electromagnetic noise in the framework of the modified Anderson theory. This explains the main features of this phenomenon, which cannot be described by quantum tunneling theory. Thus, the modified Anderson theory, which incorporates flux flow, the distribution of activation energies, the mutual interaction of the vortices, and the spatial variation of the pinning energy into the conventional Anderson theory, provides an explanation of the main features of magnetic flux creep in HTSCs.