An ultrasensitive and multispectral refractive index sensor design based on quad-supercell metamaterials

TL;DR

This paper introduces a novel quad-supercell metamaterial design supporting multiple resonance modes, achieving ultrasensitive and multispectral refractive index sensing with high sensitivity in the near-infrared spectrum.

Contribution

The paper presents a new supercell metamaterial structure with rotating split ring resonators that supports multiple resonance modes and is insensitive to polarization, enhancing multispectral sensing capabilities.

Findings

Achieved ultrahigh sensitivities of ~1000nm/RIU and ~500nm/RIU for different modes.

Supports simultaneous excitation of multiple resonance modes.

Demonstrated potential for multispectral biochemical sensing.

Abstract

Plasmonic metamaterials support the localized surface plasmon resonance (LSPR), which is sensitive to the change in the dielectric environment and highly desirable for ultrasensitive biochemical sensing. In this work, a novel design of supercell metamaterials of four mutually rotating split ring resonators (SRRs) is proposed, where simultaneous excitations of odd (N=1 and N = 3) and even (N=2) resonance modes are realized due to additional asymmetry from the rotation and show insensitivity to two orthogonal polarizations. The full utilization of these three resonance dips show bright prospects for multispectral application. As a refractive index (RI) sensor, ultrahigh sensitivities ~1000nm/RIU for LC mode (N=1) and ~500nm/RIU for plasmon mode (N=2) are obtained in near infrared (NIR) spectrum.