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arXiv · 2311.08766

Dirac Bilayer Metasurfaces as an Inverse Gires-Tournois Etalon

Ki Young Lee·Kwang Wook Yoo·Francesco Monticone·Jae Woong Yoon
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Abstract

Efficient transmissive pure-phase resonances are highly desirable for optical modulation and wavefront engineering. Here, we propose a novel principle to realize a pure-phase resonance in an extremely broad transmission band, as opposed to previous approaches restricted to operating in reflection mode or over a narrow spectral band. We show that a glide-symmetric bilayer metasurface mathematically mimicking a two-dimensional Dirac semimetal induces unidirectional guided-mode excitation and perfect leakage-radiation blazing at the transmission channel. These effects create a peculiar resonant-scattering configuration, similar to the classical reflective Gires-Tournois etalon, but in transmission, providing full 2pi phase modulation with constant transmittance near 100%. Most importantly, this effect persists over an extremely wide band, associated with topological effects. Hence, our proposed approach produces a spectrally and parametrically robust pure-phase resonance effect in transmission, which is highly beneficial for practical applications.

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Ki Young Lee, Kwang Wook Yoo, Francesco Monticone, Jae Woong Yoon. 2023-11-15. Dirac Bilayer Metasurfaces as an Inverse Gires-Tournois Etalon. https://arxiv.org/abs/2311.08766

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