Results in Physics (Mar 2020)

Dual-Fano resonances and sensing properties in the crossed ring-shaped metasurface

  • Zhihui He,
  • Chunjiang Li,
  • Wei Cui,
  • Weiwei Xue,
  • Zhenxiong Li,
  • Lihui Pu,
  • Jiaojiao Feng,
  • Xintao Xiao,
  • Xuyang Wang,
  • Yajie Liu,
  • Qirui Zou,
  • Yufei Yao,
  • Yixuan Niu,
  • Mengyuan Wang

Journal volume & issue
Vol. 16
p. 103140

Abstract

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We study dual-Fano resonances and its sensing properties in a crossed ring-shaped metasurface by use of the finite-different time-domain (FDTD) simulation. The results show that the dual-Fano resonances in the proposed crossed ring-shaped metasurface are caused by the interaction among three local surface plasmon resonances (LSPRs), and spectra of the dual-Fano resonances can be tuned by the radius of the circular ring (CR) nanostructure, the distance between the center of the two CRs in x direction, and the polarization of the incident light. Interestingly, single Fano resonance splits into dual-Fano resonances in the case of the asymmetric ring structure arrangement or the non-y-axis polarized incident or the distance d < 120 nm. Moreover, we can also find that the sensitivity for the refractive index in the proposed crossed ring-shaped metasurface can reach up to 1010 nm/RIU and 1300 nm/RIU at Fano resonance peak 1 and Fano resonance peak 2, respectively. These results may play an important role for designing high sensitive plasmonic sensors.

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