Figure of merit and sensitivity enhancement of biosensor LSPR in investigated for visible and near infrared
Résumé
We have proposed new localized surface plasmon (LSP) hybrid nanostructures, based on gold nanowires form T (AuNWs-T) deposited on a glass substrate (substrate/AuNWs) or on a graphene-coated Au film (substrate/Au film/graphene/AuNWs). The results have shown that by optimizing the parameters of nanoplasmonic structures and the incidence angle of the excitation wave. This study gives an ultra-detection performance. The detection performance parameters expressed in terms of figure of Merit (FoM) and sensitivity are improved to more than 593% (7 times) for FoM and 284.86% (3.85 times) the sensitivity compared to a traditional AuNWs-based LSPR nanostructure in normal incidence. Due to the improvement of localized surface plasmon resonance (LSPR) which is attributed to the effect of coupling between the AuNWs-T and graphene-coated Au film. This complicated nanoplasmonic resonance LSPR enhancement with the incident angle, especially in the presence of gold nanowires, can be controlled reliably by engineering the dispersion curve. These results are followed by an enhancement of the calculated electric field strength along several cut lines through the hybrid nanostructures. Our results show that the hybrid nanostructures devices hold great promise as biosensors for different types of analytes and for optical nanotechnologies.