Optimizing tunability of bound states in the continuum with graphene

Bound states in the continuum (BICs) in dielectric metasurfaces have gained significant interest for their narrow linewidths and potential applications to high-powered lasers, filters, and sensors. The resonant frequency of a BIC may be tuned by altering its dielectric environment either by changing the substrate or introducing a tunable material such as graphene. In this work, we use a gradient-descent based optimization approach to design 1D BIC metasurfaces with optical modes that exhibit extreme resonant frequency dependence on their dielectric environment. We then experimentally test our predictions by fabricating the structures, measuring their optical response, and comparing to our predictions.