TY - JOUR
T1 - Quantum nature of Gaussian discord
T2 - experimental evidence and role of system-environment correlations
AU - Chille, V.
AU - Quinn, N.
AU - Peuntinger, C.
AU - Croal, C.
AU - Mišta, L.
AU - Marquardt, C.
AU - Leuchs, G.
AU - Korolkova, N.
N1 - L.M. acknowledges Project No. P205/12/0694 of Czech Science Foundation (GACR). N.K. is grateful for the support provided by the A. von Humboldt Foundation. N.Q. and N.K. acknowledge the support from the Scottish Universities Physics Alliance (SUPA) and the Engineering and Physical Sciences Research Council (EPSRC). The project was supported within the framework of the BMBF grant “QuORep” and in the framework of the International Max Planck Partnership (IMPP) with Scottish Universities.
PY - 2015/5/13
Y1 - 2015/5/13
N2 - We provide experimental evidence of quantum features in bipartite states classified as entirely classical according to a conventional criterion based on the Glauber P function but possessing nonzero Gaussian quantum discord. Their quantum nature is experimentally revealed by acting locally on one part of the discordant state. We experimentally verify and investigate the effect of discord increase under the action of local loss and link it to the entanglement with the environment. Adding an environmental system purifying the state, we unveil the flow of quantum correlations within a global pure system using the Koashi-Winter inequality. For a discordant state generated by splitting a state in which the initial squeezing is destroyed by random displacements, we demonstrate the recovery of entanglement highlighting the role of system-environment correlations.
AB - We provide experimental evidence of quantum features in bipartite states classified as entirely classical according to a conventional criterion based on the Glauber P function but possessing nonzero Gaussian quantum discord. Their quantum nature is experimentally revealed by acting locally on one part of the discordant state. We experimentally verify and investigate the effect of discord increase under the action of local loss and link it to the entanglement with the environment. Adding an environmental system purifying the state, we unveil the flow of quantum correlations within a global pure system using the Koashi-Winter inequality. For a discordant state generated by splitting a state in which the initial squeezing is destroyed by random displacements, we demonstrate the recovery of entanglement highlighting the role of system-environment correlations.
UR - https://www.scopus.com/pages/publications/84929352825
U2 - 10.1103/PhysRevA.91.050301
DO - 10.1103/PhysRevA.91.050301
M3 - Article
AN - SCOPUS:84929352825
SN - 1050-2947
VL - 91
JO - Physical Review. A, Atomic, molecular, and optical physics
JF - Physical Review. A, Atomic, molecular, and optical physics
IS - 5
M1 - 050301(R)
ER -