Enhancement of single-photon emission from nitrogen-vacancy centers with TiN/(Al,Sc)N hyperbolic metamaterial

The broadband enhancement of single-photon emission from nitrogen-vacancy centers in nanodiamonds coupled to a planar multilayer metamaterial with hyperbolic dispersion is studied experimentally. The metamaterial is fabricated as an epitaxial metal/dielectric superlattice consisting of CMOS-compatible ceramics: titanium nitride (TiN) and aluminum scandium nitride (AlxSc1-xN). It is demonstrated that employing the metamaterial results in significant enhancement of collected single-photon emission and reduction of the excited-state lifetime. Our results could have an impact on future CMOS-compatible integrated quantum sources.