Dynamically switchable broadband and triple-band terahertz absorber based on a metamaterial structure with graphene.
Opt Express
; 30(5): 6778-6785, 2022 Feb 28.
Article
in En
| MEDLINE
| ID: mdl-35299456
ABSTRACT
This paper proposes a terahertz absorber with a simple four-layered structure that can be dynamically switched between broadband and triple-band by controlling the chemical potential of graphene. The proposed absorber owns broadband absorption in the frequency range from 5.28 THz to 7.86 THz with the corresponding absorption efficiency above 90%, when the chemical potential of graphene is 150â
meV. By increasing the chemical potential of graphene to 550â
meV, the broadband absorption splits into triple-band absorption, with the peak locating at 5.39 THz, 7.01 THz and 8.1 THz, respectively. Detailed investigation shows that the broadband absorption should originate from magnetic resonance, Fabry-Pérot cavity resonance and surface plasmon polariton. The triple-band absorption should arise from the combination of Fabry-Pérot cavity resonance and surface plasmon polariton. Additionally, both broadband absorption and triple-band absorption are insensitive to the incident polarization. This tunable and bifunctional metamaterial structure shows a great potential in terahertz applications, such as detectors, modulators and sensors.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Opt Express
Journal subject:
OFTALMOLOGIA
Year:
2022
Document type:
Article