We report the generation of passively harmonic mode-locked pulses using a 1.06 μm semiconductor optical amplifier (SOA) in a figure-eight laser configuration operated in the all-normal-dispersion regime. Different orders of harmonic mode-locking can be obtained from 30 MHz to 12.02 GHz by changing the injection current of the SOA from 80 to 660 mA together with the adjustment of polarization controllers. The highest pulse repetition rate increases almost linearly with the SOA current. As SOA current is set to 660 mA, we obtain the intracavity power of 46 mW at the highest repetition rate of 12.02 GHz, corresponding to the 1202th harmonic of the fundamental mode-locking frequency. To our best knowledge, this is the lowest intracavity power to generate the highest repetition rate with a passively mode-locked laser in the all-normal-dispersion regime.
© 2013 Optical Society of America
Lasers and Laser Optics
Original Manuscript: January 8, 2013
Revised Manuscript: February 5, 2013
Manuscript Accepted: February 7, 2013
Published: March 11, 2013
Hou-Ren Chen, Kuei-Huei Lin, Chih-Ya Tsai, Hsiao-Hua Wu, Chih-Hsuan Wu, Chieh-Han Chen, Yu-Chieh Chi, Gong-Ru Lin, and Wen-Feng Hsieh, "12 GHz passive harmonic mode-locking in a 1.06 μm semiconductor optical amplifier-based fiber laser with figure-eight cavity configuration," Opt. Lett. 38, 845-847 (2013)