Near-Field Intensity Enhancement of a nano-antenna above an inverted Bragg Reflector

Abstract

The Near-Field Intensity Enhancement (NFIE) of a Distributed Bragg Reflector has been calculated at the presence of a constructive interference at the surface of a Bragg reflector. The Bragg reflector has been constructed using SiO2/GaAs with respective refractive indices of n1=1.5 and n2=3.6. A reflectivity of 0.99986 has been simulated with an electric field enhancement approaching 2. The Bragg reflector is coupled with a Gold dipole nanoantenna to obtain a significant NFIE that is 14 times stronger than that of a Gold dipole nanoantenna above a pure silica (SiO2) surface. This significant increase is shown to be the result of the coupling effect between the Gold dipole and its mirror image.