A new class of partially coherent beams with a separable phase, which carry optical vortices, is introduced. It is shown that any member of the class can be represented as an incoherent superposition of fully coherent Laguerre–Gauss modes of arbitrary order, with the same azimuthal mode index. The free-space propagation properties of such partially coherent beams are studied analytically, and their M<sup>2</sup> quality factor is investigated numerically.
© 2001 Optical Society of America
Sergey A. Ponomarenko, "A class of partially coherent beams carrying optical vortices," J. Opt. Soc. Am. A 18, 150-156 (2001)