Plasmonic sensors with an ultra-high figure of merit. (24th December 2019)

• Record Type: Journal Article
• Authors: Liu, Zhengqi; Liu, Guiqiang; Liu, Xiaoshan; Fu, Guolan
• Is Part Of: Nanotechnology. Volume 31:Number 11(2020)
• Publication Date: 2019-12-24
• Subjects: plasmonics -- sensors -- figure of merit -- high-quality -- hybridized mode; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/ab5a00
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: We propose and numerically demonstrate a high-quality hybridized resonant platform, composed of a one-dimensional metal grating and a dielectric cavity. Under a moderate oblique illumination, an ultra-high spectral quality (Q) factor of 1375 is achieved, which shows orders of magnitude larger than that of the system under normal excitation. The high-Q mode results from the strong coupling effect between the surface plasmon polariton of the metal grating and the photonic mode of the dielectric cavity. Based on this hybridized plasmonic resonator, a high-performance sensing scheme with the spectral sensitivity ( S ) up to 800 nm/RIU (refractive index unit, RIU) is further introduced. Moreover, the figure of merit reaches 1337, indicating a new record for both the localized or propagating surface plasmons based sensors. These features could find applications in sensing and detecting devices, plasmonic switches, and light flow modulators.