Intra-cavity decomposition of a dual-directional laser beam

Abstract

A method of decomposing a dual-directional laser beam into a forward propagating field and a backward propagating field for an apertured plano-concave cavity is presented. An intra-cavity aperture is a simple method of laser beam shaping as higher-order transverse modes are discriminated. Two fundamental resonator theories, namely, Fox-Li and Laguerre-Gaussian decomposition are used in the determination of the respective beam profiles at a specific plane. A preliminary set-up is characterized for Gaussian propagation in an attempt to verify that the cavity is viable. A comparison of experimental data with the theories is presented.