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arXiv · 1701.07399

Remote Parameter Estimation in a Quantum Spin Chain Enhanced by Local Control

Jukka Kiukas·Kazuya Yuasa·Daniel Burgarth
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Abstract

We study the interplay of control and parameter estimation on a quantum spin chain. A single qubit probe is attached to one end of the chain, while we wish to estimate a parameter on the other end. We find that control on the probe qubit can substantially improve the estimation performance and discover some interesting connections to quantum state transfer.

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Jukka Kiukas, Kazuya Yuasa, Daniel Burgarth. 2017-01-25. Remote Parameter Estimation in a Quantum Spin Chain Enhanced by Local Control. https://doi.org/10.1103/physreva.95.052132

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