All-dielectric active photonics driven by bound states in the continuum

Song Han; Longqing Cong; Yogesh Kumar Srivastava; Bo Qiang; Mikhail V. Rybin; Wen Xiang Lim; Qijie Wang; Yuri S. Kivshar; Ranjan Singh

arXiv · 1803.01992

All-dielectric active photonics driven by bound states in the continuum

Song Han·Longqing Cong·Yogesh Kumar Srivastava·Bo Qiang·Mikhail V. Rybin·Wen Xiang Lim·Qijie Wang·Yuri S. Kivshar·Ranjan Singh

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Abstract

Recently emerged dielectric resonators and metasurfaces offer a low-loss platform for efficient manipulation of electromagnetic waves from microwave to visible. Such flat meta-optics can focus electromagnetic waves, generate structured beams and vortices, enhance local fields for sensing as well as provide additional functionalities for advanced MRI machinery. Recent advances are associated with exotic optical modes called bound states in the continuum, which can give rise to extremely large quality factors and supercavity lasing. Here, we experimentally demonstrate subwavelength active supercavities with extremely high-Q resonances that could be reconfigured at an ultrafast time scale. We reveal that such supercavities enable all-optical switching and modulation of extremely sharp resonances, and thus could have numerous applications in lasing, mode multiplexing, and biosensing.

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Song Han, Longqing Cong, Yogesh Kumar Srivastava, Bo Qiang, Mikhail V. Rybin, Wen Xiang Lim, Qijie Wang, Yuri S. Kivshar, Ranjan Singh. 2018-03-06. All-dielectric active photonics driven by bound states in the continuum. https://arxiv.org/abs/1803.01992

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