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DOE OSTI · 21550030

Testing quantum contextuality of continuous-variable states

McKeown, Gerard·Paternostro, Mauro·Paris, Matteo G. A.
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Abstract

We investigate the violation of noncontextuality by a class of continuous-variable states, including variations of entangled coherent states and a two-mode continuous superposition of coherent states. We generalize the Kochen-Specker (KS) inequality discussed by Cabello [A. Cabello, Phys. Rev. Lett. 101, 210401 (2008)] by using effective bidimensional observables implemented through physical operations acting on continuous-variable states, in a way similar to an approach to the falsification of Bell-Clauser-Horne-Shimony-Holt inequalities put forward recently. We test for state-independent violation of KS inequalities under variable degrees of state entanglement and mixedness. We then demonstrate theoretically the violation of a KS inequality for any two-mode state by using pseudospin observables and a generalized quasiprobability function.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSANNIHILATION OPERATORSEIGENSTATESINVARIANCE PRINCIPLESMATHEMATICAL OPERATORSPROBABILITYQUANTUM ENTANGLEMENTQUANTUM OPERATORSVARIATIONS

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McKeown, Gerard, Paternostro, Mauro, Paris, Matteo G. A.. 2011-06-15. Testing quantum contextuality of continuous-variable states. https://doi.org/10.1103/physreva.83.062105

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