Fourier-limited 1.6-ps pulses with variable repetition rate from 1 to 26 GHz by passive mode-locking of a semiconductor laser in an external cavity

By passive mode-locking of a semiconductor laser (/spl lambda/=1.3 μm) in an external cavity, 1.6 ps sech
²
-shaped pulses are generated with variable repetition rates from 1 to 26 GHz, presently limited only by the geometry of the set-up. The time-bandwidth product is between 0% and 40% over the theoretical limit. Wavelength tuning up to 50 nm is possible.