Format

Send to

Choose Destination
Nanomaterials (Basel). 2020 Feb 2;10(2). pii: E258. doi: 10.3390/nano10020258.

Perfect Absorption Efficiency Circular Nanodisk Array Integrated with a Reactive Impedance Surface with High Field Enhancement.

Author information

1
Department of Electrical Engineering, University of Ulsan, Ulsan 44610, Korea.

Abstract

Infrared (IR) absorbers based on a metal-insulator-metal (MIM) have been widely investigated due to their high absorption performance and simple structure. However, MIM absorbers based on ultrathin spacers suffer from low field enhancement. In this study, we propose a new MIM absorber structure to overcome this drawback. The proposed absorber utilizes a reactive impedance surface (RIS) to boost field enhancement without an ultrathin spacer and maintains near-perfect absorption by impedance matching with the vacuum. The RIS is a metallic patch array on a grounded dielectric substrate that can change its surface impedance, unlike conventional metallic reflectors. The final circular nanodisk array mounted on the optimum RIS offers an electric field enhancement factor of 180 with nearly perfect absorption of 98% at 230 THz. The proposed absorber exhibits robust performance even with a change in polarization of the incident wave. The RIS-integrated MIM absorber can be used to enhance the sensitivity of a localized surface plasmon resonance sensor and surface-enhanced IR spectroscopy.

KEYWORDS:

absorption efficiency; electric field enhancement factor; infrared (IR) absorber; reactive impedance surface

Supplemental Content

Full text links

Icon for Multidisciplinary Digital Publishing Institute (MDPI) Icon for PubMed Central
Loading ...
Support Center