High-Repetition-Rate Q-Switched Holmium Fiber Laser

Pulses of 118 nJ at the repetition rate of 170 kHz and central wavelength of 2097 nm have been produced by holmium fiber laser Q-switched by carbon nanotube saturable absorber. Efficient operation of holmium fiber with fairly high-doping level has been demonstrated by using refined preform fabrication, which allowed for short-length cavity laser. The results demonstrate the practical potential of holmium fibers for Q-switched lasers with high-repetition rate operating above 2 μm wavelength.