Improving field localization and figure-of-merit value in plasmonic structures via path-interference effect


ŞAHİN R.

SUPERLATTICES AND MICROSTRUCTURES, vol.133, 2019 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 133
  • Publication Date: 2019
  • Doi Number: 10.1016/j.spmi.2019.106218
  • Journal Name: SUPERLATTICES AND MICROSTRUCTURES
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Keywords: Bow-tie, Plasmonic, Path interference, Ultra-sensitive, Ultra-intense, SENSORS

Abstract

We present here an ultra-intense field localization at both on-resonant and off-resonant wave-lengths via path interference effect in nanoscale Au Bow-tie structure with single molecule coupling. First, the physics behind the Au Bow-tie with single molecule interaction is explained. Then, path-interference effect is obtained through analysis and some simulations performed with 3D Maxwell Solver (MNPBEM) in MATLAB. The coupling yields ultra-narrow resonances due to path-interference, which are very sensitive to changes into refractive index of surrounding medium. The figure-of-merit for the proposed structures is also calculated and it is demonstrated that much higher values can be obtained compared to conventional plasmonic sensors.