Tm:YGaO materials for spectrally multiplexed quantum memories
arXiv:1408.1978 · doi:10.1103/PhysRevLett.113.160501
Abstract
We investigate the relevant spectroscopic properties of the 795 nm HH transition in 1% Tm:YGaO at temperatures as low as 1.2 K for optical quantum memories based on persistent spectral tailoring of narrow absorption features. Our measurements reveal that this transition has uniform coherence properties over a 56 GHz bandwidth, and a simple hyperfine structure split by 44 MHz/T with lifetimes of up to hours. Furthermore, we find a F population lifetime of 64 ms -- one of the longest lifetimes observed for an electronic level in a solid --, and an exceptionally long coherence lifetime of 490 s -- the longest ever observed for optical transitions of Tm ions in a crystal. Our results suggest that this material allows realizing broadband quantum memories that enable spectrally multiplexed quantum repeaters.
5 pages, 3 figures