Fluctuations of polarization and magnetization in dielectric and magnetic media

Abstract

We consider thermal fluctuations of polarization, magnetization, and the associated electromagnetic fields in dielectric magnetic media which are allowed to be anisotropic and spatially nonhomogeneous. The theory is purely macroscopic and is based on an application of the fluctuation–dissipation theorem. It is shown that the correlation functions can be elegantly expressed in terms of the Green functions for Maxwell’s equations.