Third-harmonic and three-wave sum-frequency light generation in an elliptical-core optical fiber

Abstract

Third-harmonic generation and three-wave sum-frequency light generation in a short-length elliptical-core optical fiber pumped by pulses from a Q-switched and mode-locked Nd:YAG laser, operating at 1.064 μm, have been observed in the 355–385-nm spectral range. In particular, the third harmonics of the pump (λ₀ = 1.064 μm, λ₀/3 = 354.7 nm) and of the first Raman Stokes (λ₁ = 1.116 μm λ₀/3 = 372.0 nm) lines have been obtained with 5-kW peak power of the laser pulses.