Measurement of group velocity dispersion using white light interferometry:A teaching laboratory experiment

A teaching laboratory experiment is described which uses a basic Michelson interferometer arrangement to make fast and accurate measurements of the gr oup velocity dispersion of an optical material using a method based on reco rding white-light fringes. We present a brief analysis of the theory behind the technique and describe two example measurements, one of the material d ispersion of a KTP crystal and another of the reflectivity dispersion of a silver-coated mirror. Details are also given of our implementation of the d ata analysis using the MATLAB programming environment (C) 2000 American Ass ociation of Phsics Teachers.