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arXiv · 1508.06383

Decoherence of Einstein-Podolsky-Rosen steering

L. Rosales-Zárate·R. Y. Teh·S. Kiesewetter·A. Brolis·K. Ng·M. D. Reid
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Abstract

We consider two systems A and B that share Einstein-Podolsky-Rosen (EPR) steering correlations and study how these correlations will decay, when each of the systems are independently coupled to a reservoir. EPR steering is a directional form of entanglement, and the measure of steering can change depending on whether the system A is steered by B, or vice versa. First, we examine the decay of the steering correlations of the two-mode squeezed state. We find that if the system B is coupled to a reservoir, then the decoherence of the steering of A by B is particularly marked, to the extent that there is a sudden death of steering after a finite time. We find a different directional effect, if the reservoirs are thermally excited. Second, we study the decoherence of the steering of a Schr\"odinger cat state, modeled as the entangled state of a spin and harmonic oscillator, when the macroscopic system (the cat) is coupled to a reservoir.

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L. Rosales-Zárate, R. Y. Teh, S. Kiesewetter, A. Brolis, K. Ng, M. D. Reid. 2015-08-26. Decoherence of Einstein-Podolsky-Rosen steering. https://doi.org/10.1364/josab.32.000a82

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