Abstract

Short-pulse mode-locked laser diodes could become an interesting alternative to more conventional sub-picosecond lasers for time-resolved spectroscopy and optical testing of materials. Pulsewidth limits have been substantially lowered down to ~ 200 fs in recent experiments^[1,2] and still better performances are expected when considering the very large amplification bandwidth of laser diodes. However, practical applications also require high output energies (or peak-powers) and much effort has to be made in this direction. Up to now, pulse energy delivered by sub-picosecond laser diodes has been typically in the range of a few picojoules. In this paper, we report on a one-order-of-magnitude improvement of pulse energy with the use of long-stripe (1-2 mm) quantum well AlGaAs lasers in an active mode-locking scheme. The overall pulse performances attained with 2 mm long lasers (Δt ≈ 460 fs, E ≈ 50 pJ) are believed to be the best reported to date without using additional amplifier sections.

© 1994 Optical Society of America