Hybrid nanocavities for resonant enhancement of color center emission in diamond

TL;DR

This paper demonstrates resonant enhancement of diamond NV center emission using a hybrid gallium phosphide-diamond nanocavity, significantly increasing emission intensity and reducing lifetime, advancing quantum photonics applications.

Contribution

It introduces a novel hybrid nanocavity design that resonantly enhances NV center emission in diamond, achieving substantial emission increase and lifetime reduction.

Findings

Zero phonon line emission enhanced by ~10x

Spontaneous emission lifetime reduced by 18%

Achieved 6.3X emission enhancement in the zero phonon line

Abstract

Resonantly enhanced emission from the zero phonon line of a diamond nitrogen-vacancy (NV) center in single crystal diamond is demonstrated experimentally using a hybrid whispering gallery mode nanocavity. A 900 nm diameter ring nanocavity formed from gallium phosphide, whose sidewalls extend into a diamond substrate, is tuned onto resonance at low-temperature with the zero phonon line of a negatively charged NV center implanted near the diamond surface. When the nanocavity is on resonance, the zero phonon line intensity is enhanced by approximately an order of magnitude, and the spontaneous emission lifetime of the NV is reduced as much as 18%, corresponding to a 6.3X enhancement of emission in the zero photon line.