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Title: Broadband Absorption in Patterned Metal/Weakly-Absorbing-Spacer/Metal with Graded Photonic Super-Crystal
It is challenging to realize the complete broadband absorption of near-infrared in thin optical devices. In this paper, we studied high light absorption in two devices: a stack of Au-pattern/insulator/Au-film and a stack of Au-pattern/weakly-absorbing-material/Au-film where the Au-pattern was structured in graded photonic super-crystal. We observed multiple-band absorption, including one near 1500 nm, in a stack of Au-pattern/spacer/Au-film. The multiple-band absorption is due to the gap surface plasmon polariton when the spacer thickness is less than 30 nm. Broadband absorption appears in the near-infrared when the insulator spacer is replaced by a weakly absorbing material. E-field intensity was simulated and confirmed the formation of gap surface plasmon polaritons and their coupling with Fabry–Pérot resonance.  more » « less
Award ID(s):
1661842
NSF-PAR ID:
10299575
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Photonics
Volume:
8
Issue:
4
ISSN:
2304-6732
Page Range / eLocation ID:
114
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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