General relation between spatial coherence and absorption

Abstract

In this supplementary material, we provide the detailed derivation of the quantities used in the paper: the cross-spectral density tensor, which describes the correlation of the electric and magnetic fields spontaneously emitted, the mixed losses, which describes the power a structure absorbs when it is illuminated by electric and magnetic currents, and the relation between both. We also provide an original derivation of the cross-density of states (CDOS) introduced in [1] by considering the power emitted by two monochromatic point-like current sources in free space.