Experimental validation of quantum steering ellipsoids and tests of volume monogamy relations
Abstract
The set of all qubit states that can be steered to by measurements on a correlated qubit is predicted to form an ellipsoid---called the quantum steering ellipsoid---in the Bloch ball. This ellipsoid provides a simple visual characterisation of the initial 2-qubit state, and various aspects of entanglement are reflected in its geometric properties. We experimentally verify these properties via measurements on many different polarisation-entangled photonic qubit states. Moreover, for pure 3-qubit states, the volumes of the two quantum steering ellipsoids generated by measurements on the first qubit are predicted to satisfy a tight monogamy relation, which is strictly stronger than the well-known monogamy of entanglement for concurrence. We experimentally verify these predictions, using polarisation and path entanglement. We also show experimentally that this monogamy relation can be violated by a mixed entangled state, which nevertheless satisfies a weaker monogamy relation.
Keywords
Cite
@article{arxiv.1809.08011,
title = {Experimental validation of quantum steering ellipsoids and tests of volume monogamy relations},
author = {Chao Zhang and Shuming Cheng and Li Li and Qiu-Yue Liang and Bi-Heng Liu and Yun-Feng Huang and Chuan-Feng Li and Guang-Can Guo and Michael J. W. Hall and Howard M. Wiseman and Geoff J. Pryde},
journal= {arXiv preprint arXiv:1809.08011},
year = {2019}
}