CMOS compatible metamaterial absorbers for hyperspectral medium wave infrared imaging and sensing applications

James Grant, Mitchell Kenney, Yash D. Shah, Ivonne Escorcia-Carranza, David R. S. Cumming
2018 Optics Express  
We experimentally demonstrate a CMOS compatible medium wave infrared metalinsulator-metal (MIM) metamaterial absorber structure where for a single dielectric spacer thickness at least 93% absorption is attained for 10 separate bands centred at 3.08, 3.30, 3.53, 3.78, 4.14, 4.40, 4.72, 4.94, 5.33, 5.60 μm. Previous hyperspectral MIM metamaterial absorber designs required that the thickness of the dielectric spacer layer be adjusted in order to attain selective unity absorption across the band of
more » ... across the band of interest thereby increasing complexity and cost. We show that the absorption characteristics of the hyperspectral metamaterial structures are polarization insensitive and invariant for oblique incident angles up to 25° making them suitable for practical implementation in an imaging system. Finally, we also reveal that under TM illumination and at certain oblique incident angles there is an extremely narrowband Fano resonance (Q > 50) between the MIM absorber mode and the surface plasmon polariton mode that could have applications in hazardous/toxic gas identification and biosensing.
doi:10.1364/oe.26.010408 pmid:29715978 fatcat:yvmza6hrzrbedjnsfnnzxrsb4u