We introduce an advanced material system for the production and spectroscopy of single silicon vacancy (SiV) color centers in diamond. We use microwave plasma chemical vapor deposition to synthesize heteroepitaxial nanodiamonds of approximately 160 nm in lateral size with a thickness of approximately 75 nm. These oriented “nanoislands” combine the enhanced fluorescence extraction from subwavelength-sized nanodiamonds with defined crystal orientation. The investigated SiV centers display narrow zero-phonon lines down to 0.7 nm in the wavelength range 730–750 nm. We investigate in detail the phonon coupling and vibronic sidebands of single SiV centers, revealing significant inhomogeneous effects. Polarization measurements reveal polarized luminescence and preferential absorption of linearly polarized light.

• Received 18 August 2011

DOI:https://doi.org/10.1103/PhysRevB.84.205211