Coherence Properties of Blackbody Radiation. III. Cross-Spectral Tensors

Abstract

In a recent paper, cross-spectra tensors of quantized stationary electromagnetic fields were introduced and some of their properties were discussed. In the present paper, closed expressions for the cross-spectral tensors of blackbody radiation are derived and their behavior is illustrated by a number of diagrams. It is found that the correlation distance of a spectral component of wavelength $\lambda$ is itself of the order of $\lambda$ and is therefore independent of the temperature of the radiation.