  We propose an approach to enhance and direct the spontaneous emission from
isolated emitters embedded inside hyperbolic metamaterials into single photon
beams. The approach rests on collective plasmonic Bloch modes of hyperbolic
metamaterials which propagate in highly directional beams called quantum
resonance cones. We propose a pumping scheme using the transparency window of
the hyperbolic metamaterial that occurs near the topological transition.
Finally, we address the challenge of outcoupling these broadband resonance
cones into vacuum using a dielectric bullseye grating. We give a detailed
analysis of quenching and design the metamaterial to have a huge Purcell factor
in a broad bandwidth inspite of the losses in the metal. Our work should help
motivate experiments in the development of single photon sources for broadband
emitters such as nitrogen vacancy centers in diamond.
