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arXiv · 1704.05734

Continuous variable steering and incompatibility via state-channel duality

Jukka Kiukas·Costantino Budroni·Roope Uola·Juha-Pekka Pellonpää
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Abstract

The term Einstein-Podolsky-Rosen steering refers to a quantum correlation intermediate between entanglement and Bell nonlocality, which has been connected to another fundamental quantum property: measurement incompatibility. In the finite-dimensional case, efficient computational methods to quantify steerability have been developed. In the infinite-dimensional case, however, less theoretical tools are available. Here, we approach the problem of steerability in the continuous variable case via a notion of state-channel correspondence, which generalizes the well-known Choi-Jamiołkowski correspondence. Via our approach we are able to generalize the connection between steering and incompatibility to the continuous variable case and to connect the steerability of a state with the incompatibility breaking property of a quantum channel, e.g., noisy NOON states and amplitude damping channels. Moreover, we apply our methods to the Gaussian steering setting, proving, among other things, that canonical quadratures are sufficient for steering Gaussian states.

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Jukka Kiukas, Costantino Budroni, Roope Uola, Juha-Pekka Pellonpää. 2017-11-07. Continuous variable steering and incompatibility via state-channel duality. https://doi.org/10.1103/physreva.96.042331

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