1ps passively mode-locked laser operation of Na,Yb:CaF2 crystal.

Diode-pumped passively mode-locked laser operation of Yb3+,Na+:CaF2 single crystal has been demonstrated for the first time. By using a SESAM (semiconductor saturable mirror), simultaneous transform-limited 1-ps passively mode-locked pulses, with the repetition rate of 183MHz, were obtained under the self-Q-switched envelope induced by the laser medium. The average output power of 360mW was attained at 1047nm for 3.34W of absorbed power at 976nm, and the corresponding pulse peak power arrived at 27kW, indicating the promising application of Yb3+,Na+ - codoped CaF2 crystals in achieving ultra-short pulses and high pulse peak power.