Efficient 559.6 nm light produced by sum-frequency generation of diode-end-pumped Nd:YAG/SrWO4 Raman laser

Abstract

An efficient yellow-green laser at 559.6 nm based on the sum-frequency generation of diode-end-pumped Nd:YAG/SrWO4 Raman laser is demonstrated. The 45 mm in length SrWO4 crystal grown by Czochralski method and the KTP crystal with a type-II critical phase matching (θ = 83.4°, ϕ = 0°) cut were adopted for Raman conversion and sum-frequency generation, respectively. The maximum average power of 2.41 W was achieved at the incident pump power of 20.4 W and the pulse repetition rate of 60 kHz. The overall diode-yellow conversion efficiency was 11.8% and the slope efficiency was about 24%. The results show that the critical pump power of resonator instability is increasing with the pulse repetition rate.