Highly sensitive and actively tunable chiral metasurface enabled by bound states in the continuum
Year: 2024
Type: article
Abstract: Chiroptical metasurfaces are novel materials capable of manipulating the polarization state of light. The active tuning of chiroptical metasurfaces further empowers the capability of real-time and wide-range manipulation of light. In this study, we propose and investigate a dielectric metasurface based on LiNbO 3 that enables active and efficient electro-optic tuning of chiroptical responses. We have observed a quasi-bound state in the continuum (q-BIC) in this metasurface, which exhibits a large circular dichroism (CD) of 0.89 and a high Q-factor of 9.3 × 10 4 at 976.26 nm. Owing to the high Q-factor, the CD can be electro-optically modulated by up to 0.83 with a high sensitivity of 8 × 10 −5 nm/(V/m), which is orders of magnitude higher than that of bulk LiNbO 3 modulators. In addition, the polarization states of both linearly and circularly polarized light can be efficiently tuned through this metasurface, with tunable ranges of rotation angle and ellipticity up to 78° and 62°, respectively. We believe that the proposed chiroptical metasurface is an excellent candidate as a compact, versatile, and highly sensitive electro-optic modulator.
Source: Optics Express
DOI: 10.1364/oe.540676
Institution: University of South China
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
OpenAlex ID: W4403198195