A compact passively Q-switched Tm-Ho codoped crystal laser at 2 μm with narrow pulse duration

A Tm,Ho:YVO4 laser with compact geometry was demonstrated and analyzed. For the continuous wave laser, the slope efficiency of 30.5% was achieved. By inserting a Cr:ZnS saturable absorber into the cavity, the passively Q-switched laser generated almost constant pulse duration of 83 ns with the slope efficiency of 19.3%. The pulse energy was also independent of the pump power, around 130 mu J. Through increasing the pump power from 3.7 W to 8.1 W, the pulse repetition varied approximately linearly from 2.9 kHz to 6.8 kHz. The Q-switch efficiency of the PQS laser is up to 58% at the maximum pump power.

Automated summary

A Tm,Ho:YVO4 laser with compact geometry was demonstrated and analyzed in this study, achieving a slope efficiency of 30.5% for continuous wave operation and 19.3% for passively Q-switched mode with a Cr:ZnS saturable absorber. The pulse energy was consistent at around 130 μJ regardless of pump power, and the pulse repetition rate varied linearly from 2.9 kHz to 6.8 kHz as pump power increased. The Q-switch efficiency reached up to 58% at maximum pump power.