Fundamental-mode laser-beam propagation in optically inhomogeneous electrochemical media with chemical species concentration gradients

Abstract

Solutions to Maxwell’s wave equation have been derived for the propagation of the fundamental (Gaussian) mode of a laser beam in a fluid electrolyte which is in contact with an active electrode. An electrochemical or photoelectrochemical reaction at the electrolyte–electrode interface is assumed to generate a concentration gradient of the product in the electrolyte, which results in an inhomogeneous refractive-index profile. The analytic solutions for the propagation of the beam explicitly demonstrate the dependence of the displacement of the intensity centroid and of the spot shape on the electrochemical parameters of the system.