Birefringence phase-matched direct third-harmonic generation in a ridge optical waveguide based on a KTiOPO4 single crystal

Birefringence phase-matched third-harmonic generation at 1594 nm is performed for the first time in a KTiOPO4 single crystal micrometric ridge waveguide. The energy conversion efficiency reaches 3.4% for a pump energy as low as 2 mu J over a pulse duration of 15 ps at a repetition rate of 10 Hz. Strong agreements between theory and experiments for both phase-matching and conversion efficiency is obtained, which let us envision future triple photon generation quantum experiments. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

Birefringence phase-matched third-harmonic generation at 1594 nm was achieved for the first time in a KTiOPO4 single crystal micrometric ridge waveguide. The energy conversion efficiency reached 3.4% with a low pump energy of 2 mu J and pulse duration of 15 ps at a repetition rate of 10 Hz. Strong agreement between theory and experiments suggests potential for future triple photon generation quantum experiments.