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arXiv · 2210.05655

Adjoint optimization of polarization-splitting grating couplers

Peng Sun·Thomas Van Vaerenbergh·Sean Hooten·Raymond Beausoleil
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Abstract

We have designed a polarization-splitting grating coupler (PSGC) in silicon-oninsulator (SOI) that has 1.2 dB peak loss in numerical simulations, which is the best simulated performance of PSGCs without a bottom reflector to the best of our knowledge. Adjoint method-based shape optimization enables us to explore complex geometries that are intractable with conventional design approaches. Physics-based process-independent knowledge of PSGCs is extracted from the adjoint optimization and can be transferred to other platforms with a minimum of effort.

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Peng Sun, Thomas Van Vaerenbergh, Sean Hooten, Raymond Beausoleil. 2022-10-11. Adjoint optimization of polarization-splitting grating couplers. https://doi.org/10.1364/oe.477532

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