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arXiv · 1612.02390

Quantum parameter estimation with the Landau-Zener transition

Jing Yang·Shengshi Pang·Andrew N. Jordan
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Abstract

We investigate the fundamental limits in precision allowed by quantum mechanics from Landau-Zener transitions, concerning Hamiltonian parameters. While the Landau-Zener transition probabilities depend sensitively on the system parameters, much more precision may be obtained using the acquired phase, quantified by the quantum Fisher information. This information scales with a power of the elapsed time for the quantum case, whereas it is time-independent if the transition probabilities alone are used. We add coherent control to the system, and increase the permitted maximum precision in this time-dependent quantum system. The case of multiple passes before measurement, "Landau-Zener-Stueckelberg interferometry", is considered, and we demonstrate that proper quantum control can cause the quantum Fisher information about the oscillation frequency to scale as $T^4$, where $T$ is the elapsed time.

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Jing Yang, Shengshi Pang, Andrew N. Jordan. 2016-12-07. Quantum parameter estimation with the Landau-Zener transition. https://doi.org/10.1103/physreva.96.020301

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