Title of Paper:Perfect ultra-narrow band absorber based on lamellar structure for refractive index sensing

Hits:

Date of Publication:2019-01-01

Included Journals:CPCI-S

Volume:11209

Key Words:Nanostructures; narrowband; perfect absorption; biosensing

Abstract:In this paper, we theoretically investigate a tunable ultra-narrow band absorber consisting of lamellar structure in the near-infrared wavelength range. The absorption efficiency is 99.9% under normal incidence and the full width at half maximum (FWHM) is only 4nm. The high absorption is attributed to the surface plasmon resonance (SPR), which increases the interaction volume of the optical field. The ultra-narrow band absorber has a high refractive index sensitivity of 1208nm/RIU in a wide refractive index range of 1.33 to 1.40 and a high figure of merit of 302. Besides, the influence of structure parameters on the sensing performance are also investigated. Due to its easiness to be fabricated, the proposed structure has potential in sensing application.