Recently, the subject on "plasmonics'' has received significant attention in designing surface plasmon resonance (SPR) sensors. In order to achieve extremely high-sensitivity sensing, multilayered configurations based on a variety of active materials and dielectrics have been exploited. In this work, a novel SPR sensor is proposed and investigated theoretically. The structure, analyzed in attenuated total reflection (ATR), consists of multilayer interfaces between gold and a metamaterial (LHM) separated by an analyte layer as a sensing medium. By interchanging between gold and LHM, under the effect of the refractive index (RI) of analyte set to be in the range of 1.00 to 1.99, the sharp peak reflectivity at the SPR angle takes two opposite behaviors predicted from the transfer matrix method. At the threshold value of 1.568 of the refractive index of analyte and when the LHM is the outer medium, the layered structure exhibits a giant sharp peak located at 43° of intensity up to 10 5 due to the Goos-Hànchen effect. With respect to the refractive index (RI) change and thickness of analyte, the characteristics (intensity, resonance condition, and quality factor) of the SPR mode, which make the proposed device have the potential for biosensing applications, have been analytically modelized.

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The purpose of this work is to investigate theoretically the characteristics of confined electromagnetic modes propagating along the interfaces of a multilayer device. This one dimensional (ID) sensor is formed by stacking a left-handed material (LHM) layer between a SiCt2-glass prism and a dielectric gap layer in contact with gold (Au). The results indicate that the total thickness of the LHM layer and dielectric gap, in optimum conditions, give the ability of tuning significantly the characteristics of the resonant modes correlated to surface plasmons (SPs) propagation along the interfaces of the designed device. By considering two arrangements between LHM and Au, two opposite resonant behaviors observed in p-reflectance spectra are analyzed in the angular interrogation mode and discussed thoroughly.

Background: The paper reports on typical characteristics of resonant electromagnetic modes propagation through interfaces of a multilayer device. Objective: Using the transfer matrix method, p-reflectance is analyzed in angular interrogation for a symmetrical cavity performed with left-handed metamaterial layer mediated with GaAs. Result: An advantage of SPR sensor is demonstrated in terms of optimal performances by controlling thicknesses, refractive indices and dielectric gap layers of the media involved. Conclusion: The functionality of the proposed design, as a tunable filter, has been also identified.

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.