New method of soft modes investigation by Little-Parks effect

Abstract

As is known, Little-Parks effect concerned with oscillations of the critical temperature of a superconducting transition was one of the first effects which suggested the existence of Cooper pairing in conventional superconductors. It is shown that in high-temperature superconductors (HTSC) the Little-Parks effect based on bipolaron mechanism which in HTSC is the equivalent of Cooper pairing can be anomalously high. The results obtained can be used as a new method for detecting soft phonon modes in nanostructures on the basis of HTSC. The results can be also used to enhance the critical temperature of a superconducting transition.