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arXiv · 2304.05815

Bayesian Estimation for Bell State Rotations

Luke Anastassiou·Jason F. Ralph·Simon Maskell·Pieter Kok
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Abstract

This paper explores the effect of three-dimensional rotations on two-qubit Bell states and proposes a Bayesian method for the estimation of the parameters of the rotation. We use a particle filter to estimate the parameters of the rotation from a sequence of Bell state measurements and we demonstrate that the resultant improvement over the optimal single qubit case approaches the $\sqrt{2}$ factor that is consistent with the Heisenberg limit. We also demonstrate how the accuracy of the estimation method is a function of the purity of mixed states.

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Luke Anastassiou, Jason F. Ralph, Simon Maskell, Pieter Kok. 2023-04-12. Bayesian Estimation for Bell State Rotations. https://arxiv.org/abs/2304.05815

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