Fluctuation-Induced Diamagnetism and Statistics of the Fluctuation Modes in a Superconductor

Abstract

Introducing boson-like excitations to describe the fluctuation of the order parameter in a superconductor near the transition temperature, we have calculated the fluctuation-induced diamagnetism and found a result in excellent agreement with the recent experiment of Gollub, Beasley, and Tinkham. We find that the effective density of boson excitations just above the transition temperature is of order of ${10}^{-6\mathrm{}}N$, where $N$ is the density of electrons, and vanishes at high temperatures.