Abstract

In femtosecond mode-locked lasers, dispersion plays a critical role in the mode-locking physics. With the advent of new broad bandwidth solid-state gain media that could support pulses of less than 10 fs duration in principle, dispersive effects are becoming more important and represent a barrier for further progress. Previously, dispersion in individual cavity elements has been measured with femtosecond accuracy. In this talk, we discuss a new technique for measurement of intracavity dispersion in operating mode-locked femtosecond lasers. Using a frequency-domain technique, we measure the frequency dependent group delay with ±0.65 fs accuracy. We discuss limits imposed by the high order dispersion in such lasers and also extend the technique to cover intracavity spectroscopy and nonlinear effects.

© 1992 Optical Society of America