Optical limiting using Laguerre-Gaussian beams

We demonstrate optical limiting using the self-lensing effect of a higher-order Laguerre-Gaussian beam in a thin dye-doped polymer sample, which we find consistent with our model using Gaussian decomposition. The peak phase shift in the sample required for limiting is smaller than that for a fundamental Gaussian beam with the added flexibility that the nonlinear medium can be placed either in front of or behind the beam focus. (c) 2007 American Institute of Physics.