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arXiv · 1509.06516

Criticality of environmental information obtainable by dynamically controlled quantum probes

Analia Zwick·Gonzalo A. Alvarez·Gershon Kurizki
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Abstract

A universal approach to decoherence control combined with quantum estimation theory reveals a critical behavior, akin to a phase transition, of the information obtainable by a qubit probe concerning the memory time of environmental fluctuations. This criticality emerges only when the probe is subject to dynamical control. It gives rise to a sharp transition between two dynamical phases characterized by either a short or long memory time compared to the probing time. This phase-transition of the environmental information is a fundamental feature that facilitates the attainment of the highest estimation precision of the environment memory-time and the characterization of probe dynamics.

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Analia Zwick, Gonzalo A. Alvarez, Gershon Kurizki. 2015-09-22. Criticality of environmental information obtainable by dynamically controlled quantum probes. https://doi.org/10.1103/physreva.94.042122

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