Propagation Properties of the Rectangular Multi-Gaussian Schell-Model Beams in Uniaxial Crystals Orthogonal to the Optical Axis

Abstract

A stochastic beam generated by a recently introduced source of Schell type with rectangular multi-Gaussian spectral degree of coherence is shown to posses interesting novel features on propagation in uniaxial crystals. The analytical expression for the cross-spectral density function of the rectangular multi-Gaussian Schell-model (RMGSM) beams propagating in uniaxial crystals orthogonal to the optical axis is derived. With the help of the derived formula, the evolution properties of the spectral density, the effective beam width, and the spectral degree of coherence of the RMGSM beams in a uniaxial crystal are investigated in detail. It is shown that the evolution properties of an RMGSM beam in uniaxial crystal are much different from its evolution properties in free space, and the propagation properties of the RMGSM beams in uniaxial crystals are closely related to the initial beam parameters (beam index M and spatial coherence length) and the parameters of the uniaxial crystals (the ratio of extraordinary and ordinary refractive indices). The results demonstrate the potential of uniaxial crystals for modulating the properties of the RMGSM beams.