We theoretically and numerically demonstrate enhanced extended superradiance using a diamond epsilon near-zero (ENZ) metamaterial design. Due to the large spatial coherence in this metamaterial we experience an ultra-high superradiant decay rate enhancement over distances greater than 13 times the free-space wavelength for both two emitters and many-body configurations of emitters. We observe a power enhancement three orders of magnitude higher than an incoherent array of emitters in bulk diamond, corresponding to an
N2 scaling with the number of emitters characteristic of superradiance. With similar simulation and design methods, we numerically and analytically demonstrate highly robust, extended entanglement in diamond mu near-zero (MNZ) metamaterials by calculating the concurrence in this system. Robust entanglement is maintained for distances over 10 microns and for distances over 20 times larger in free space configurations and for extended timescales in transiently entangled systems. we apply these optical metamaterial systems to the the silicon vacancy center (SiV) in diamond as a candidate quantum emitter. By simulating the Hamiltonian of two Raman-tuned SiV centers and coupling it to a theoretical 1-D near zero refractive index (NZRI) waveguide with a Dirac-like dispersion, we observe enhanced superradiance via calculating the second order photon correlation function
g(2)(τ) and observing signatures ultra-indistinguishable photons emitted from the superradiant system of 2 SiVs. We demonstrate the feasibility of these NZRI metamaterial designs by fabricating a planar epsilon and mu near-zero (EMNZ) metamaterial design of diamond pillars on single crystal bulk diamond. Additionally, we demonstrate fabrication of angle-etched suspended diamond ENZ waveguides. These are proof-of-concept fabrications for any potential experimental realizations in the future.
We demonstrate cavity-enhanced Raman emission from a single atomic defect in a solid. Our platform is a single silicon-vacancy center in diamond coupled with a monolithic diamond photonic crystal cavity. The cavity enables an unprecedented frequency tuning range of the Raman emission (100 GHz) that significantly exceeds the spectral inhomogeneity of silicon-vacancy centers in diamond nanostructures. We also show that the cavity selectively suppresses the phonon-induced spontaneous emission that degrades the efficiency of Raman photon generation. Our results pave the way towards photon-mediated many-body interactions between solid-state quantum emitters in a nanophotonic platform.