HIGH-POWER, SHORT-PULSE ACOUSTOOPTICALLY Q-SWITCHED FIBER LASER

Short pulse, high peak power Q-switching of fibre lasers is demonstrated using a specially constructed TeO2 acousto-optic modulator with high diffraction efficiency at 1.06 mum. The laser emits > 0.7 kW peak power pulses with 2.8 ns duration at up to 1 kHz repetition rates for an absorbed pump power of 13 mW under zeroth order operation with average rf power of 50 mW. Under first order operation we obtained > 150 W peak power pulses with a 4 ns duration using average rf driving power of 0.5 mW. Exact numerical integration of the laser kinetic rate equations yields good agreement with the experimental results.