Neutral Silicon-Vacancy Center in Diamond: Spin Polarization and Lifetimes

• Published in: Physical review letters 2017-09, Vol.119 (9), p.096402-096402, Article 096402
• Main Authors: Green, B L, Mottishaw, S, Breeze, B G, Edmonds, A M, D'Haenens-Johansson, U F S, Doherty, M W, Williams, S D, Twitchen, D J, Newton, M E
• Format: Article
• Language: English
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.119.096402

We demonstrate optical spin polarization of the neutrally charged silicon-vacancy defect in diamond (SiV^{0}), an S=1 defect which emits with a zero-phonon line at 946 nm. The spin polarization is found to be most efficient under resonant excitation, but nonzero at below-resonant energies. We measure an ensemble spin coherence time T_{2}>100  μs at low-temperature, and a spin relaxation limit of T_{1}>25  s. Optical spin-state initialization around 946 nm allows independent initialization of SiV^{0} and NV^{-} within the same optically addressed volume, and SiV^{0} emits within the telecoms down-conversion band to 1550 nm: when combined with its high Debye-Waller factor, our initial results suggest that SiV^{0} is a promising candidate for a long-range quantum communication technology.