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arXiv · 1710.11355

Necessary Condition for Steerability of Arbitrary Two-Qubit States with Loss

Travis J. Baker·Sabine Wollmann·Geoff J. Pryde·Howard M. Wiseman
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Abstract

Einstein-Podolsky-Rosen steering refers to the quantum phenomenon whereby the state of a system held by one party can be "steered" into different states at the will of another, distant, party by performing different local measurements. Although steering has been demonstrated in a number of experiments involving qubits, the question of which two-qubit states are steerable remains an open theoretical problem. Here, we derive a necessary condition for any two-qubit state to be steerable when the steering party suffers from a given probability of qubit loss. Our main result finds application in one-way steering demonstrations that rely upon loss. Specifically, we apply it to a recent experiment on one-way steering with projective measurements and POVMs, reported by Wollmann et. al. [Phys. Rev. Lett., 116, 160403 (2016)].

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Travis J. Baker, Sabine Wollmann, Geoff J. Pryde, Howard M. Wiseman. 2017-10-31. Necessary Condition for Steerability of Arbitrary Two-Qubit States with Loss. https://doi.org/10.1088/2040-8986%2Faaaa3c

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