A Theoretical Terahertz Metamaterial Absorber Structure with a High Quality Factor Using Two Circular Ring Resonators for Biomedical Sensing

Abstract

Metamaterial absorbers, on account of their inherent property of electromagnetic radiation absorption, have become a center of attraction for many researchers in recent times. This paper proposes a unique design of a terahertz metamaterial absorber that can be used to sense biomedical samples. The proposed design consists of two identical circular ring resonators (CRRs) made of aluminum on top of a gallium arsenide (GaAs) substrate. On account of its high field confinement in the sensing regime, a near-to-perfect absorption rate of 99.50% is achieved at a frequency of 2.64 THz, along with a large quality factor (Q-Factor) of 44. The design is highly sensitive to the refractive index changes in the encompassing medium. Hence, the proposed absorber can be used as a refractive index sensor exhibiting a reasonable sensitivity of 1500 GHz/RIU and a figure of merit (FoM) of 25. The refractive index range has been varied in the range of 1.34 to 1.39. As many biomedical samples, including cancerous cells, reside within this range, the proposed sensor can be used for biomedical sensing applications.

Highly sensitive refractive index sensing with a dual-band optically transparent ITO-based perfect metamaterial absorber for biomedical applications

“…Electromagnetic (EM) metamaterials are a class of composite engineered materials having qualities that exhibit unusual electromagnetic phenomena not present in natural materials [1] , [2] , [3] , [4] . Researchers have researched it extensively for studying negative refractive index, super lenses, tiny wireless components [5] , [6] , [7] , [8] , [9] , [10] , and absorbers [11] , [12] , [13] , [14] , [15] , etc. because it offers many unusual strategies to manipulate light [16] .…”

Ultrathin metamaterial-based refractive index sensor for biomedical applications

“…Lately, many researchers investigated metamaterial based RI sensor, and found it is highly reliant to the surrounding medium changes [23,[28][29][30][31]. The RI sensors based on metamaterial designs has real time detection and quick response which can be employed in biomedical sensing applications [32][33][34][35][36].…”

Simple design of metamaterial sensor for biomedical sensing

“…The recent work of S Banerjee et al [53] suggested RI sensor composed of two identical circular rings for biomedical sensing. The structure offers Q factor 44 and FOM 25.…”