Increasing entanglement between Gaussian states by coherent photon subtraction.
We experimentally demonstrate that the entanglement between Gaussian entangled states can be increased by non-Gaussian operations. Coherent subtraction of single photons from Gaussian quadrature-entangled light pulses, created by a nondegenerate parametric amplifier, produces delocalized states with negative Wigner functions and complex structures more entangled than the initial states in terms of negativity. The experimental results are in very good agreement with the theoretical predictions.
Ourjoumtsev
Alexei
A
Laboratoire Charles Fabry de l'Institut d'Optique, CNRS UMR 8501, 91403 Orsay, France. alexei.ourjoumtsev@institutoptique.fr
Dantan
Aurélien
A
Tualle-Brouri
Rosa
R
Grangier
Philippe
P