High efficiency active Q-switched laser operation with a large size rectangular core crystalline waveguide

High efficient pulse output from a large size rectangular core crystalline waveguide actively Q-switched laser was achieved experimentally. A crystalline waveguide, with a rectangular core size of 320 mu mx400 mu m by 1.0at.% Yb:YAG (core), 600 mu mx600 mu m by 0.5at.% Er:YAG (cladding), and 7mmx7mm by 4.0at.% V:YAG (outside of the cladding) was designed and fabricated. Using a continuous diode laser as an end pump, an output pulse energy 1.75mJ@10kHz, pulse width 9.9ns (peak power 175kW), optical-optical efficiency 26%, with the beam quality of M-x(2)=1.15, M-y(2)=1.10, were obtained in the experiment. The design method that used to suppress amplified spontaneous emission (ASE) and parasitic oscillation by cutting off the reflection and transmission paths, can be applied for various kinds of crystalline waveguide Q-switched or mode-locked lasers. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

High efficient pulse output was achieved experimentally from a large size rectangular core crystalline waveguide actively Q-switched laser. The design using a continuous diode laser as an end pump resulted in high output pulse energy, optical-optical efficiency, and good beam quality, which can be applied for various types of crystalline waveguide lasers.