Abstract
In this work, the design and analysis of a butterfly-shaped perfect absorber is presented for Terahertz applications. The
proposed absorber has compact dimensions of 16×16 µm2
. It comprises three layers, a butterfly-shaped metallic patch on
the uppermost layer, a middle layer of Teflon and a metallic ground plane at the bottom. The perfect narrow absorption
peak is observed at 4.7 THz with an absorption value of 99%. The design exhibits a fourfold symmetry with a tolerance of
60⁰ for an angle of incidence and is polarisation insensitive. Further, the designed butterfly-shaped absorber is used to
sense the analyte with a refractive index ranging from 1 to 3.16 exhibiting an average sensitivity value of 786 GHz/RIU for
fixed analyte thickness. The compact and unique design of the sensor enhances its sensing performance, indicating its
potential for various applications such as biomedical sensing, hazardous substance detection, and disease diagnosis.
Keywords
Metamaterial, THz sensors, Sensitivity, Polarization and absorber.
Citation
GEETIKA, R. S. KALER, A compact highly sensitive refractive index sensor using a butterfly-shaped absorber for terahertz biomedical applications, Optoelectronics and Advanced Materials - Rapid Communications, 18, 9-10, September-October 2024, pp.411-418 (2024).
Submitted at: March 13, 2024
Accepted at: Oct. 2, 2024