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arXiv · 2007.08104

Quasibound states in the continuum in terahertz free-standing metal complementary periodic cross-shaped resonators

Dejun Liu·Feng Wu·Lin Chen·Feng Liu
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Abstract

We numerically and experimentally achieve quasi-bound states in the continuums (BICs) with high-Q factors in the free-standing metal complementary periodic cross-shaped resonators (CPCRs) at terahertz (THz) frequencies. Such induced quasi-BICs arises from the breaking of the mirror symmetry of CPCRs. By properly tuning the asymmetric factor, the measured Q factor of quasi-BIC can reach 102, which is lower than the simulated Q factor of 166 due to the limited system resolutions. We also simulate the electric field magnitude and vector distributions at the quasi-BICs, where the out-phase alignment between the electric dipoles is found. The sharp quasi-BICs realized in this thin free-standing metal structure may immediately boost the performance of filters and sensors in terahertz wave manipulation or biomolecular sensing.

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Dejun Liu, Feng Wu, Lin Chen, Feng Liu. 2020-07-16. Quasibound states in the continuum in terahertz free-standing metal complementary periodic cross-shaped resonators. https://arxiv.org/abs/2007.08104

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