Study on damage mechanism of SESAM in high power ultrafast laser

With the development of ultrafast laser to high power and high pulse energy, it is necessary to study damage mechanism of Semiconductor saturable absorber mirror (SESAM) and high threshold SESAM. Damage mechanism of SESAM in high power ultrafast laser is theoretically analyzed and experimentally observed in this paper. The damage mechanism on surface of SESAM is studied by heat imaging of SESAM in working high power ultrafast laser with thermal imager and the SESAM surface damaged by high power femtosecond laser pulses is also analyzed. Both heat damage of SESAM and the influential factors are studied in this paper.