HIGHLY FE-DOPED InGaAs/InP SATURABLE ABSORBER MODE-LOCKING OF AN ERBIUM FIBER LASER

Abstract

Erbium-doped unidirectional fiber ring laser has been passively mode-locked with a novel ultra-fast semiconductor saturable absorber used in transmission. The structure is based on InGaAs/InP multiple quantum wells grown on an InP substrate. Different structures with recovery time down to picosecond have been tested. Relaxation time reduction have been obtained by iron doping. With such structures, detrimental regimes such as Q-switch and Q-switch/ModeLock regimes have been avoided. Solitonic and slightly stretched-pulse dispersion regimes have been tested. The laser delivers for both, completely self-starting picosecond pulses of 8 mW maximum average output power at a repetition rate around 25 MHz.