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arXiv · 1810.06393

400%/W second harmonic conversion efficiency in $\mathrm{14 μm}$-diameter gallium phosphide-on-oxide resonators

Alan D. Logan·Michael Gould·Emma R. Schmidgall·Karine Hestroffer·Zin Lin·Weiliang Jin·Arka Majumdar·Fariba Hatami·Alejandro W. Rodriguez·Kai-Mei C. Fu
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Abstract

Second harmonic conversion from 1550~nm to 775~nm with an efficiency of 400% W$^{-1}$ is demonstrated in a gallium phosphide (GaP) on oxide integrated photonic platform. The platform consists of doubly-resonant, phase-matched ring resonators with quality factors $Q \sim 10^4$, low mode volumes $V \sim 30 (λ/n)^3$, and high nonlinear mode overlaps. Measurements and simulations indicate that conversion efficiencies can be increased by a factor of 20 by improving the waveguide-cavity coupling to achieve critical coupling in current devices.

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Alan D. Logan, Michael Gould, Emma R. Schmidgall, Karine Hestroffer, Zin Lin, Weiliang Jin, Arka Majumdar, Fariba Hatami, Alejandro W. Rodriguez, Kai-Mei C. Fu. 2018-10-10. 400%/W second harmonic conversion efficiency in $\mathrm{14 μm}$-diameter gallium phosphide-on-oxide resonators. https://doi.org/10.1364/oe.26.033687

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