Passive stabilization of a passively mode-locked laser by nonlinear absorption in indium phosphide.
A diode-pumped Nd:KGd(WO4)2 laser mode locked by a saturable Bragg reflector (SBR) is passively stabilized to suppress Q-switched mode locking and to extend the parameter range of continuous-wave mode locking. An indium phosphide plate exhibiting two-photon absorption and free-carrier absorption is used for passive stabilization. The intracavity pulse energy for the onset of stable continuous-wave mode locking is reduced by a factor of 4 compared with the laser without stabilization. By increasing the modulation depth of the SBR, pulse shortening by 30% is achieved and bandwidth-limited 6.2-ps pulses are measured.
Cerný
Pavel
P
Institute of Photonics, University of Strathclyde, 106 Rottenrow, Glasgow G40 NW, UK. pavel.cerny@strath.ac.uk
Valentine
Gareth
G
Burns
David
D
McEwan
Kenneth
K