Diode-pumped 915-nm Pr:YLF laser passively mode-locked with a SESAM

A diode-pumped, passively mode-locked laser emitting at 915 nm with a praseodymium-doped yttrium lithium fluoride (Pr:YLF) crystal was demonstrated for the first time, to the best of our knowledge. Utilizing two polarization-combined blue pumping laser diodes (LDs) and a semiconductor saturable absorber mirror (SESAM), stable continuous-wave (CW) mode-locking operations were achieved with a maximum average output power of 408 mW and a slope efficiency of 10.8%. Laser pulse durations of 15 ps were obtained with a spectral full width at half maximum (FWHM) of 0.15 nm and a repetition rate of 1.53 GHz.