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arXiv · 1803.06061

Inverse Design of Compact Multimode Cavity Couplers

Weiliang Jin·Sean Molesky·Zin Lin·Kai-Mei C. Fu·Alejandro W. Rodriguez
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Abstract

Efficient coupling between on-chip sources and cavities plays a key role in silicon photonics. However, despite the importance of this basic functionality, there are few systematic design tools to simultaneously control coupling between multiple modes in a compact resonator and a single waveguide. Here, we propose a large-scale adjoint optimization approach to produce wavelength-scale waveguide--cavity couplers operating over tunable and broad frequency bands. We numerically demonstrate couplers discovered by this method that can achieve critical, or nearly critical, coupling between multi-ring cavities and a single waveguide at up to six widely separated wavelengths spanning the $560$--$1500$~nm range of interest for on-chip nonlinear optical devices.

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Weiliang Jin, Sean Molesky, Zin Lin, Kai-Mei C. Fu, Alejandro W. Rodriguez. 2018-09-03. Inverse Design of Compact Multimode Cavity Couplers. https://doi.org/10.1364/oe.26.026713

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