Efficient second harmonic generation in χ (2) profile reconfigured lithium niobate thin film

• DOI: 10.1016/j.optcom.2016.10.064
• Publication Date: 2016-11-03T18:18:02Z
• Authors: Lutong Cai; Yiwen Wang; Hui Hu
• Keywords: Modal dispersion

Abstract Second harmonic wave was efficiently generated in proton exchanged lithium niobate thin film channel waveguides. Modal dispersion phase matching was achieved between two guided modes at pump and second-harmonic wavelengths with the same polarization, enabling using the largest second-order nonlinear component d 33 . The χ (2) profile in the lithium niobate thin film was reconfigured by proton exchange, leading to significantly enhanced modal overlap integral between the interacting modes. Normalized conversion efficiency up to 48% W − 1 cm −2 was achieved in experiments.