High slope efficiency and low threshold in a laser-diode-pumped passively Q-switched ion-implanted Nd:YVO _4 planar waveguide laser with GaAs saturable absorber

摘要

A passively Q-switched waveguide laser, to our knowledge, has been firstly demonstrated in Nd: YVO _4 crystal formed by 3 MeV Si ~+ ion implantation at a dose of 1 × 10 ~(15) ions/cm ~2 at room temperature, in which GaAs was used as saturable absorber. The dependences of the average output power, pulse width, pulse repetition rate on absorbed pump power have been measured at different output plane mirror transmissions. At an absorbed pump power of 78.8 mW and output transmission of 20%, the shortest pulse width of 3.88 ns was obtained, corresponding to the peak power and single pulse energy of 212 W and 0.82 μJ, respectively. The threshold pump power was as low as 40 mW, and the slope efficiency was about 64.5% when the absorbed pump power was lower than 70 mW.