Spectral description of fluctuating electromagnetic fields of solids using a self-consistent approach

A new way to evaluate the spectral-correlation properties of thermal fields of solids is suggested. The principal element here is the surface linear response function of an inhomogeneous electron subsystem of solids. Along with straightforward calculations using the known response functions, the suggested method allows calculating the response functions self-consistently based on the time dependent density functional theory. The self-consistent calculation of the linear response function followed by an application of the fluctuation-dissipation theorem yields spectral power densities of the fluctuating electromagnetic fields.