Control of spontaneous emission with functionalized multilayered hyperbolic metamaterials

The behavior of spontaneous emission of emitters embedded inside metamaterials with hyperbolic dispersion has been investigated. A simple technique has been developed to fabricate lamellar metal-dielectric hyperbolic metamaterials on substrates which can be flat, flexible or curvilinear in geometry. Moreover, this method opens up the possibility of functionalizing the dielectric layers by dye molecules. Utilizing this technique, we study the spontaneous emission kinetics of emitters placed either on top, or embedded inside hyperbolic metamaterials. While we observe a reduction in the radiative lifetimes in both cases, owing to the singularity in the density of photonic states, the effect is much stronger when the dye molecules are inside the metamaterial, rather than on its surface.