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arXiv · 1710.06691

Geometric Steering Criterion for Two-qubit States

Bai-Chu Yu·Zhih-Ahn Jia·Yu-Chun Wu·Guang-Can Guo
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Abstract

According to the geometric characterization of measurement assemblages and local hidden state (LHS) models, we propose a steering criterion which is both necessary and sufficient for two-qubit states under arbitrary measurement sets. A quantity is introduced to describe the required local resources to reconstruct a measurement assemblage for two-qubit states. We show that the quantity can be regarded as a quantification of steerability and be used to find out optimal LHS models. Finally we propose a method to generate unsteerable states, and construct some two-qubit states which are entangled but unsteerable under all projective measurements.

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Bai-Chu Yu, Zhih-Ahn Jia, Yu-Chun Wu, Guang-Can Guo. 2017-10-18. Geometric Steering Criterion for Two-qubit States. https://doi.org/10.1103/physreva.97.012130

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