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arXiv:1605.04279 · Scientific Reports

Sharp transitions in low-number quantum dots Bayesian magnetometry

Paweł Mazurek, Michał Horodecki, Łukasz Czekaj, Paweł Horodecki

Published Sep 30, 2016• 1 citation
arXivHTMLPDF

Abstract

We consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine interaction. Sudden transitions among optimal states and measurements are observed. Usefulness of measuring occupation levels is shown for all times of the evolution, together with the role of entanglement in the optimal scenario. For low values of magnetic field, memory effects stemming from the interaction with environment provide limited metrological advantage.

DOI
10.1038/srep34327

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