Micro bench for optical pulse picking from 4 GHz pulse trains generated by mode locking of DBR lasers

A new compact picosecond light source is presented. It consists of a master oscillator, an ultra fast pulse picker element and integrated high-frequency electronics arranged on a micro bench with a footprint of 5 cm × 4 cm. The master oscillator is a laser consisting of 200 μm long saturable absorber, 1500 μm long gain, 8000 μm long cavity, 200 μm long DBR and 100 μm long monitor sections. Pulses with a width of 10 ps and a peak power of 0.5 W are generated by hybrid mode locking. Despite the 1 cm long cavity, the repetition rate is still 4.3 GHz. The semiconductor pulse picking element is based on a ridge waveguide acting as an optical gate and a tapered gain section for pulse amplification. The light source emits pulses with with a peak power of more than 30 W pulse peak power and allows a free choice of the repetition rate in the range between 1 kHz and 100 MHz.