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arXiv · 1610.04197

Second harmonic generation in nano-structured thin-film lithium niobate waveguides

Cheng Wang·Xiao Xiong·Nicolas Andrade·Vivek Venkataraman·Xi-Feng Ren·Guang-Can Guo·Marko Lončar
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Abstract

Integrated thin-film lithium niobate platform has recently emerged as a promising candidate for next-generation, high-efficiency wavelength conversion systems that allow dense packaging and mass-production. Here we demonstrate efficient, phase-matched second harmonic generation in lithographically-defined thin-film lithium niobate waveguides with sub-micron dimensions. Both modal phase matching in fixed-width waveguides and quasi-phase matching in periodically grooved waveguides are theoretically proposed and experimentally demonstrated. Our low-loss (~ 3.0 dB/cm) nanowaveguides possess normalized conversion efficiencies as high as 41% W-1cm-2.

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Cheng Wang, Xiao Xiong, Nicolas Andrade, Vivek Venkataraman, Xi-Feng Ren, Guang-Can Guo, Marko Lončar. 2016-10-13. Second harmonic generation in nano-structured thin-film lithium niobate waveguides. https://doi.org/10.1364/oe.25.006963

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