摘要
A periodically-poled LiNbO3(PPLN) crystal features space-dependent second-order nonlinear coefficients, which is one of the most important materials to effectively control nonlinear optical interactions through quasi-phase matching(QPM). By using electric-field poling method, 1D and 2D PPLN crystals have been successfully fabricated for laser frequency conversion, quantum light sources, nonlinear beam shaping and nonlinear optical imaging. Recently, femtosecond laser engineering technique is utilized to prepare 3D domain structures inside LiNbO3 crystal, which provides a promising platform to control nonlinear interacting waves in 3D configuration. After 40 years of developments, PPLN crystals still have exciting prospects in fundamental researches and practical applications for integrated photonic chip, quantum information processing,and so on.
基金
supported by the National Key R&D Program of China(Grant Nos. 2017YFA0303703 and 2016YFA0302500)
the National Natural Science Foundation of China (Grant Nos. 91950206,11874213 and11674171)
the Fundamental Research Funds for the Central Universities (Grant Nos. 14380105 and 1480605201)。
