Room temperature picosecond mode-locked pulse generation from a 1.55µm VECSEL with an InGaAsN/GaAsN fast saturable absorber mirror

Abstract

A 1.55µm VECSEL with a metal-GaAs/AlAs hybrid metamorphic mirror optimized for high power room temperature operation has been assembled with a fast saturable absorber mirror (SESAM) in a four-mirror cavity to generate mode-locked pulses at a frequency of 2 GHz. Stable pulses are obtained at room temperature avoiding the need for water cooling, with a pulsewidth < 2 ps and an average optical power at the output coupling mirror of 10 mW. The RF linewidth of the free running laser has been measured to be less than 1000 Hz.