All-optical clock division with mode-locked figure-eight laser based on the slow carrier recovery rate in semiconductor optical amplifier

With a mode-locked figure-eight laser, we demonstrate the clock division operation using a semiconductor optical amplifier (SOA) with a slow carrier recovery rate. We show stable clock division at 2.5 GHz and two output states at half the repetition rate of the 10-GHz input pulses. The forming pulses in the laser cavity will interact with each other at the onset of mode locking when the SOA in the laser has a relatively slow carrier recovery rate. A numerical model of the laser is built to simulate the generation of clock division