Ju Y, Zhou H, Zhao Y, Wang F, Yang Z, Deng X, Wu Z, Guoliang D, Zuo H. Hybrid resonance metasurface for a lithium niobate electro-optical modulator.
OPTICS LETTERS 2022;
47:5905-5908. [PMID:
37219133 DOI:
10.1364/ol.474784]
[Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 10/15/2022] [Indexed: 05/24/2023]
Abstract
Electrically tunable metasurfaces can realize two-dimensional pixelated spatial light modulation and have a wide range of applications in optical switching, free-space communication, high-speed imaging, and so on, arousing the interest of researchers. Here, a gold nanodisk metasurface on a lithium-niobate-on-insulator (LNOI) substrate is fabricated and experimentally demonstrated as an electrically tunable optical metasurface for transmissive free-space light modulation. Using the hybrid resonance formed by the localized surface plasmon resonance (LSPR) of gold nanodisks and the Fabry-Perot (FP) resonance, the incident light is trapped in the gold nanodisk edges and a thin lithium niobate layer to realize field enhancement. In this way, an extinction ratio of 40% is achieved at the resonance wavelength. In addition, the proportion of hybrid resonance components can be adjusted by the size of the gold nanodisks. By applying a driving voltage of ± 2.8 V, a dynamic modulation of 135 MHz is achieved at resonant wavelength. The highest signal-to-noise ratio (SNR) is up to 48 dB at 75 MHz. This work paves the way for the realization of spatial light modulators based on CMOS-compatible LiNbO3 planar optics, which can be used in lidar, tunable displays, and so on.
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