Nonclassical correlations between a C-band telecom photon and a stored spin-wave

 9 September 2016

Our group demonstrate nonclassical correlation between a frequency-converted telecom C-band photon and a spin-wave stored in an atomic ensemble quantum memory. The scientific results of this study have been published in Optica.

The photons emitted from the ensemble and heralding the spin-waves are converted from 780 to 1552 nm by means of an all-solid-state integrated-waveguide nonlinear device. We show ultra-low-noise operation of the device, enabling a high signal-to-noise ratio for the converted single photon, leading to a high spin-wave heralding efficiency. The presented work is an enabling step toward the practical entanglement of remote quantum memories and the entanglement of quantum systems operating at different wavelengths.

The research team that participated in this study includes Pau Farrera, Nicolas Maring, Dr. Boris Albrecht, Dr. Georg Heinze, and Prof. Hugues de Riedmatten.

Reference :

Storage Enhanced Nonlinearities in a Cold Atomic Rydberg Ensemble 
E. Distante, A. Padrón-Brito, M. Cristiani, D. Paredes-Barato, and H. de Riedmatten
Optica Vol. 3, Issue 9, pp. 1019-1024 (2016) (see also arXiv:1607.01350)