ASYMMETRIC PLASMONIC NANO-BOWTIES FOR ELECTROMAGNETIC ENHANCEMENT

Abstract

Plasmonic nanostructures, which are properly engineered, lead to the phenomenon of localized surface plasmon resonance (LSPR), wherein, an enhance electric field near the surface of metal nanoparticles at the plasmon resonance wavelength can be observed. This phenomenon finds applications in many areas such as photo-voltaics, refractive index sensing and others. In this project, plasmonic nano-structures which offer high electromagnetic enhancement through the formation of EM hotspots, and due to the lightning rod effect are analyzed by employing Finite Difference Time Domain (FDTD) simulations. In the first part of the project, nano-spheres were simulated in an attempt to understand resonance and see the effect of introducing a second metal on the resonance spectrum. In the second part, the plasmonic properties of homo-structured bimetallic nano-bowties were exhaustively analyzed by varying different geometrical parameters. In the third part, the effect of breaking the symmetry of nano-bowties on the hybridized plasmonic modes created in these nanostructures will be simulated. The E-field enhancement will be calculated and the passive tunability of the plasmon resonance wavelength by varying the structural parameters will be numerically demonstrated.