Terahertz biosensing metamaterial absorber for virus detection based on spoof surface plasmon polaritons

Abstract

As a promising candidate for rapid and ultrasensitive sensing of biomolecules, terahertz (THz) time-domain spectroscopy is widely used in label-free, noncontact, noninvasive, and nondestructive detection. In this article, planar Jerusalem cross metamaterial absorber for different virus detection based on spoof surface plasmon polaritons (SSPPs) in THz band is investigated. Strongly confined SSPPs modes are extracted from the absorption spectra of biosensing metamaterial absorber associated with local field enhancement. Meanwhile, equivalent complex refractive index (N) of different virus subtypes and protein concentrations is numerically investigated for virus detection. Besides, simulated detections for different virus subtypes (different N) are probed with the proposed biosensing metamaterial absorber. Especially for the simulated detections of three representative Avian Influenza viruses (H5N2, H1N1, H9N2), the proposed THz biosensing metamaterial absorber chip performed ultrasensitive sensitivity and high resolution by extracting the shifted resonance frequencies (ΔF) and the changed values at maximum absorptions (ΔA). All these findings show great significance on a rapid real-time procedure for diseases diagnosis especially for the contagious and time-sensitive target virus. The proposed ultrasensitive and selective THz metamaterial absorber opens up a new way for planar biosensing chip to be developed into practical applications in THz regime.