Measurement of the group-delay dispersion of femtosecond optics using white-light interferometry

Abstract

A compact and practical white-light cross-correlator suitable for fast evaluation of femtosecond optics, in terms of group-delay dispersion, was developed. A 40-W tungsten-halogen lamp was used as a white-light source and the detector selection was made so as to have adequate spectral sensitivity from 600 to 1050 nm, peaked at 800 nm. Group-delay dispersion was obtained, with femtosecond time resolution, from the Fourier transform of the cross-correlation interferogram. The dispersion characteristics of a borosilicate glass plate, broadband femtosecond mirrors, broadband chirped mirrors, and output couplers of different reflectivity have been determined in the wavelength range of 650 to 1050 nm. (C) 2004 American Institute of Physics.