Direct Structural Identification and Quantification of the Split-Vacancy Configuration for Implanted Sn in Diamond

We demonstrate formation of the ideal split-vacancy configuration of the Sn-vacancy center upon implantation into natural diamond. Using beta-emission channeling following low fluence 121Sn implantation (2E12 atoms/cm2, 60 keV) at the ISOLDE facility at CERN, we directly identified and quantified the atomic configurations of the Sn-related centers. Our data show that the split-vacancy configuration is formed immediately upon implantation with a surprisingly high efficiency of ~40%. Upon thermal annealing at 920°C ~30% of Sn is found in the ideal bond-center position. Photoluminescence revealed the characteristic SnV- line at 621 nm, with an extraordinarily narrow ensemble linewidth (2.3 nm) of near-perfect Lorentzian shape. These findings further establish the SnV- center as a promising candidate for single photon emission applications, since, in addition to exceptional optical properties, it also shows a remarkably simple structural formation mechanism.