Article ID Journal Published Year Pages File Type
739931 Optics & Laser Technology 2006 4 Pages PDF
Abstract

The increasing use of low power cw lasers in various applications calls for the design of optical limiters with low thresholds. To this end, the optical nonlinearity exhibited by zinc tetraphenyl porphyrin at low laser powers is utilized to design an optical limiter for low threshold operation. The basic parameter responsible for limiting action, the nonlinear refractive index of the medium, is measured using the Z  -scan technique and found to have a value of -1.4×10-7cm2/W at the helium–neon laser wavelength of 632.8 nm. The origin of nonlinearity is explained on the basis of the thermal lens model. It is shown that effective optical limiting at desired threshold values can be achieved by the optimal choice of aperture size and experimental geometry.

Related Topics
Physical Sciences and Engineering Engineering Electrical and Electronic Engineering
Authors
, , ,