A dual-band polarization independent dielectric metasurface-based absorber for sensing application in the visible light regime

Abstract

We present a dual-band, polarization-independent dielectric terahertz absorber exhibiting near-perfect absorption and minimal reflection at frequencies of f1 = 419 THz and f2 = 528 THz. Using electromagnetic theory, we modeled the structure to derive the surface electric admittance and magnetic impedance of the metasurface, elucidating the conditions required for perfect absorption in terms of inverse electric and magnetic polarizabilities. The absorber features a tunable symmetrical design, facilitating precise frequency adjustment by modifying structural parameters and ensuring polarization independence for perpendicularly incident electromagnetic waves. This scalable and versatile absorber, constructed from readily available materials, is optimally suited for applications in resource detection, imaging, sensing, and medical diagnostics, attributed to its simplicity, cost-effectiveness, and high performance.