Rare earth ions in crystals exhibit narrow spectral features and hyperfine-split ground states with exceptionally long coherence times. These features make them ideal platforms for quantum information processing in the solid state. Recently, we reported on the first high-resolution spectroscopy of single Pr3+ ions in yttrium orthosilicate (YSO) nanocrystals. While in that work we examined the less explored 3H4-3P0 transition at a wavelength of 488 nm, here we extend our investigations to the 3H4-1D2 transition at 606 nm. In addition, we present measurements of the second-order autocorrelation function, fluorescence lifetime, and emission spectra of single ions as well as their polarization dependencies on both transitions; these data were not within the reach of the first experiments reported earlier. Furthermore, we show that by a proper choice of the crystallite, one can obtain narrower spectral lines and, thus, resolve the hyperfine levels of the excited state. We expect our results to make single-ion spectroscopy accessible to a larger scientific community.
@article{arxiv.1504.00857,
title = {High-resolution spectroscopy of single Pr$^{3+}$ ions on the $^3$H$_4$-$^1$D$_2$ transition},
author = {Emanuel Eichhammer and Tobias Utikal and Stephan Götzinger and Vahid Sandoghdar},
journal= {arXiv preprint arXiv:1504.00857},
year = {2015}
}