@article{Cai2018,
   abstract = {The inherent trade-off between efficiency and bandwidth of three-wave mixing processes in χ2 nonlinear waveguides is the major impediment for scaling down many well-established frequency conversion schemes onto the level of integrated photonic circuit. Here, we show that hybridization between modes of a silica microfiber and a LiNbO3 nanowaveguide, amalgamated with laminar χ2 patterning, offers an elegant approach for engineering broadband phase matching and high efficiency of three-wave mixing processes in an ultra-compact and natively fiber-integrated setup. We demonstrate exceptionally high normalized second harmonic generation (SHG) efficiency of up to ηnor ≈ 460% W−1 cm−2, combined with a large phase matching bandwidth of Δλ ≈ 100 nm (bandwidth-length product of Δλ · L ≈ 5 μm2) near the telecom bands, and extraordinary adjustment flexibility.},
   author = {Lutong Cai and Andrey V. Gorbach and Yiwen Wang and Hui Hu and Wei Ding},
   doi = {10.1038/s41598-018-31017-0},
   issn = {2045-2322},
   issue = {1},
   journal = {Scientific Reports},
   keywords = {Integrated optics,Nonlinear optics},
   month = {12},
   pages = {12478},
   publisher = {Nature Publishing Group},
   title = {Highly efficient broadband second harmonic generation mediated by mode hybridization and nonlinearity patterning in compact fiber-integrated lithium niobate nano-waveguides},
   volume = {8},
   url = {http://www.nature.com/articles/s41598-018-31017-0},
   year = {2018}
}