A terahertz metamaterial absorber, capable of detecting cancerous cells is proposed in this paper. The proposed design consists of several merged Circular Ring Resonators (CRRs) (CRRs) over a Gallium Arsenide substrate. It achieves an absorption of 99% at 3.71 THz and a high Quality factor (Q-factor) of 92.75. The resonance frequency shifts with alterations in refractive index of the encompassing medium and this is used for detecting cancerous cells. The refractive index has been varied in the range of 1.35 to 1.40 on account of the fact that many of the cancer cells are in this range and its sensitivity is found to be 1447 GHz/RIU. The sensor's high Q factor and a Figure of Merit (FoM) of 36.175 has several biomedical sensing applications.

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.