Comparative Study on Sensing Characteristics of Optical Surface Plasmon Resonance Sensors Using A Single LHM-Dielectric Interface: A Theoretical Study

Abstract

This work addresses a theoretical analysis on optical planar surface plasmon resonance (SPR) sensors. The proposed plasmonic system consists of an active left-handed material (LHM) stacked between a glass-prism and a sensing environment. To evaluate the limits of the surface sensitivity related to SPR excitation, two arrangements between previous media are separately investigated for comparison. Employing the transfer matrix method (TMM), angular TM-reflectance calculations and intrinsic sensing characteristics of previous arrangements, have been investigated with the impact of thicknesses and refractive index (RI) of the media involved. We found the suitable prism material RI, and the preferential arrangement between LHM and sensing environment allowing, thus the increase of the detection sensitivity of SPR excitation. The results of TM-reflectance obtained by varying the sensing environment RI, indicate the ability of the configuration to support an surface plasmon (SP) mode, with a tunable Q-factor from 72 to 748. In addition, distinct optical functionalities achieved with the proposed mono-layer LHM system exhibiting a single SPR mode, and multiple resonant oscillations, are highlighted on both the effects of RI and structure ‘thicknesses. Finally, the relationships between characteristics of TM-reflectance spectra versus the performance parameters are analytically derived.