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arXiv · 1810.09235

Ultrahigh-efficiency second-harmonic generation in nanophotonic PPLN waveguides

Cheng Wang·Carsten Langrock·Alireza Marandi·Marc Jankowski·Mian Zhang·Boris Desiatov·Martin M. Fejer·Marko Loncar
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Abstract

Periodically poled lithium niobate (PPLN) waveguide is a powerful platform for efficient wavelength conversion. Conventional PPLN converters however typically require long device lengths and high pump powers due to the limited nonlinear interaction strength. Here we use a nanostructured PPLN waveguides to demonstrate an ultrahigh normalized efficiency of 2600%/W-cm$^2$ for second-harmonic generation of 1.5-$μ$m radiation, more than 20 times higher than that in state-of-the-art diffused waveguides. This is achieved by a combination of sub-wavelength optical confinement and high-fidelity periodic poling at a first-order poling period of 4 $μ$m. Our highly integrated PPLN waveguides are promising for future chip-scale integration of classical and quantum photonic systems.

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Cheng Wang, Carsten Langrock, Alireza Marandi, Marc Jankowski, Mian Zhang, Boris Desiatov, Martin M. Fejer, Marko Loncar. 2018-09-24. Ultrahigh-efficiency second-harmonic generation in nanophotonic PPLN waveguides. https://doi.org/10.1364/optica.5.001438

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