Theoretical study of enhancement of spontaneous emission by hyperbolic metamaterials nanoparticles

Abstract

Spontaneous emission, the process by which an emitter in an excited state transitions spontaneously to the ground state by emitting a photon, is at the center of several applications from spectroscopy to efficient light sources. The decay rate is highly dependent of the environment and through the last decades, considerable efforts have been made to modify spontaneous emission using microcavities, photonic crystals or plasmonic nanoantennas. In this thesis, we tackle the problem of enhancement of spontaneous emission by hyperbolic metamaterials nanoantennas. The materials produce large density of states which enhance the transition rate. With transformation optics, we study the use of asymmetrical metamaterials nanoantennas and show how the asymmetry can suppress the spontaneous emission quenching. For arbitrary shaped and lossy anisotropic materials, we derive a modal expansion based on the eigenpermittivity modes and Green’s function to study the scattering and nearfield properties.