Experimental demonstration of a silicon-slot quasi-bound state in the continuum in near-infrared all-dielectric metasurfaces Articles uri icon

authors

  • ALGORRI GENARO, JOSE FRANCISCO
  • Dell'Olio, F.
  • DING, Y.
  • LABBE, F.
  • DMITRIEV, V.
  • LÓPEZ-HIGUERA, J. M.
  • SANCHEZ PENA, JOSE MANUEL
  • ANDREANI, L. C.
  • GALLI, M.
  • ZOGRAFOPOULOS, DIMITRIOS

publication date

  • June 2023

volume

  • 161

International Standard Serial Number (ISSN)

  • 0030-3992

Electronic International Standard Serial Number (EISSN)

  • 1879-2545

abstract

  • We theoretically and experimentally investigate a metasurface supporting a silicon-slot quasi-bound state in the continuum (qBIC) mode resonating in the near-infrared spectrum. The metasurface is composed of circular slots etched in a silicon layer on a sapphire substrate. The symmetry of the metasurface unit cell is reduced in order to provide access to the symmetry-protected mode, whose properties are investigated by finite-element full-wave and eigenfrequency analysis. The measured transmittance spectra verify the excitation of the investigated qBIC mode with experimental quality factors exceeding 700. The near-field distribution of the resonant qBIC mode shows strong field confinement in the slots, leading to high sensitivity values for refractometry.

subjects

  • Electronics

keywords

  • biosensing; bound states in the continuum; metamaterials; nanofabrication; silicon metasurfaces; symmetry-protected modes