We demonstrate a high-Q perfect light absorber based on all-dielectric doubly-resonant metasurface.Leveraging bound states in the continuum(BICs)protected by different symmetries,we manage to independently manipulate ...We demonstrate a high-Q perfect light absorber based on all-dielectric doubly-resonant metasurface.Leveraging bound states in the continuum(BICs)protected by different symmetries,we manage to independently manipulate the Q factors of the two degenerate quasi-BICs through dual-symmetry perturbations,achieving precise matching of the radiative and nonradiative Q factors for degenerate critical coupling.We achieve a narrowband light absorption with a>600 Q factor and a>99%absorptance atλ_(0)=1550 nm on an asymmetric germanium metasurface with a 0.2λ_(0)thickness.Our work provides a new strategy for engineering multiresonant metasurfaces for narrowband light absorption and nonlinear applications.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62105172 and 62005236)the Zhejiang Provincial Natural Science Foundation(No.LQ21F050004)+1 种基金the Ningbo Natural Science Foundation(No.202003N4102)the K.C.Wong Magna Fund in Ningbo University。
文摘We demonstrate a high-Q perfect light absorber based on all-dielectric doubly-resonant metasurface.Leveraging bound states in the continuum(BICs)protected by different symmetries,we manage to independently manipulate the Q factors of the two degenerate quasi-BICs through dual-symmetry perturbations,achieving precise matching of the radiative and nonradiative Q factors for degenerate critical coupling.We achieve a narrowband light absorption with a>600 Q factor and a>99%absorptance atλ_(0)=1550 nm on an asymmetric germanium metasurface with a 0.2λ_(0)thickness.Our work provides a new strategy for engineering multiresonant metasurfaces for narrowband light absorption and nonlinear applications.