Devising genuine cross-spectral densities by randomization of coherent fields

Abstract

We propose a concept of devising the authentic cross spectral densities (CSDs) of partially coherent beam waves by averaging the second moment of a coherent field over a certain number of random parameters. Several CSD examples created by randomization are presented. We discuss application of randomization to generation of twisted Gaussian Schell model beams and show that compound randomization leads to a new, more general class of twisted beams. We revisit the necessary nonnegative definiteness condition of Opt. Lett. 34, 1399 (2009)OPLEDP0146-959210.1364/OL.34.001399 and show that the two-dimensional space of parameters is necessary.