Fig. 2: Characterisation of a typical laser-activated single tin vacancy (SnV−) centre.
From: Laser activation of single group-IV colour centres in diamond
a Room-temperature photoluminescence (PL) spectrum from a single site in the array implanted with 10 ions per site, exhibiting the characteristic SnV− centre emission. The inset shows a PL image of the site and its nearby surroundings. b Spectrum at 4.2 K of the same site, showing the γ and δ optical transitions typical of a SnV− centre. The inset shows the basic energy level structure and the optical transitions of the SnV− centre. The off-resonant excitation is indicated in green. c Histogram showing the background-corrected second-order auto-correlation measurement of PL emitted from the same site as in panels (a, b). The red curve corresponds to a three-level model \({g}^{(2)}(\delta t)=1-(1+\alpha ){e}^{-\frac{| \delta t| }{{\tau }_{1}}}+\alpha {e}^{-\frac{| \delta t| }{{\tau }_{2}}}\), with fitted values τ1 = 1.4 ± 1.5 ns and τ2 = 9.7 ns. The red shaded region represents one standard error. d Polarisation dependence of the integrated emission of all zero-phonon lines (ZPLs, black), as well as the γ (blue) and δ (orange) optical transitions as a function of analysing polariser angle. The integrated ZPL intensity is normalised to its maximum value, while the γ and δ lines are normalised relative to the maximum intensity of the γ line.
