Abstract

Ultrafast optical pulses with a broad spectrum are very useful in studying materials. The usual way to generate white-light pulses is done by highly nonlinear processes. The generated white light is noisy, not well collimated, and not uniform across the beam. We report the use of synchronously pumped dye lasers to generate stable well-collimated broadband pulses with durations in the pico­second to femtosecond range. The broadband comes from two effects: the fast gain modulation and the gain peak suppression. The fast gain modulation transfers power from high gain modes to low gain modes and makes them oscillate. A transmission valley is then introduced into the cavity and makes the gain minus loss curve flat. The number of oscillation modes can thus be further increased.

© 1988 Optical Society of America