Morphology dependent shape resonances by optical fiber encaved nanoantenna for refractive index sensing

Abstract

We present the numerical study to demonstrate excitation of morphology dependent resonances in microresonator by an encaved nanoantenna surrounded by conical cavity in an optical fiber. The microresonator is excited by a focused beam coming from the nanoantenna when placed off-axially to it. The resonances show Lorentzian and Fano peaks having Quality factor, Q of the order of ~105. The proposed design can be experimentally fabricated by chemical etching of a photosensitive fiber. The design has potential to sense the change in dielectric environment having sensitivity ~31.832nm/ RIU.