Experimental Verification of Quantum Discord in Continuous-Variable States
arXiv:1310.6796 · doi:10.1088/0953-4075/47/2/025503
Abstract
We introduce a simple and efficient technique to verify quantum discord in unknown Gaussian states and a certain class of non-Gaussian states. We show that any separation in the peaks of the marginal distributions of one subsystem conditioned on two different outcomes of homodyne measurements performed on the other subsystem indicates correlation between the corresponding quadratures, and hence nonzero discord. We also apply this method to non-Gaussian states that are prepared by overlapping a statistical mixture of coherent and vacuum states on a beam splitter. We experimentally demonstrate this technique by verifying nonzero quantum discord in a bipartite Gaussian and certain class of non-Gaussian states.
14 pages, 6 figures
References in corpus (11)
- Quantum discord and the power of one qubit
- Necessary and sufficient condition for non-zero quantum discord
- Entanglement in continuous variable systems: Recent advances and current perspectives
- Interpreting quantum discord through quantum state merging
- Operational interpretations of quantum discord
- Operational Significance of Discord Consumption: Theory and Experiment
- Experimentally Witnessing the Quantumness of Correlations
- Homodyne estimation of Gaussian quantum discord
- Experimental Investigation of the Evolution of Gaussian Quantum Discord in an Open System
- Detecting Multipartite Classical States and their Resemblances
- Verification of quantum discord
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