Open AccessEnhanced dual-band infrared absorption in a Fabry-Perot cavity with subwavelength metallic grating
Author(s) -
Guoguo Kang,
Ismo Vartiainen,
Benfeng Bai,
Jari Turunen
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.000770
Subject(s) - optics , infrared , materials science , detector , grating , optoelectronics , absorption (acoustics) , fabry–pérot interferometer , multi band device , diffraction grating , spectral bands , infrared detector , physics , telecommunications , wavelength , computer science , antenna (radio)
The performance of infrared (IR) dual-band detector can be substantially improved by simultaneously increasing IR absorptions for both sensor bands. Currently available methods only provide absorption enhancement for single spectral band, but not for the dual-band. The Fabry-Perot (FP) cavity generates a series of resonances in multispectral bands. With this flexibility, we introduced a novel type of dual-band detector structure containing a multilayer FP cavity with two absorbing layers and a subwavelength-period grating mirror, which is capable of simultaneously enhancing the middle wave infrared (MWIR) and the long wave infrared (LWIR) detection. Compared with the bare-absorption-layer detector (common dual-band detector), the optimized FP cavity can provide about 13 times and 17 times absorption enhancement in LWIR and MWIR bands respectively.