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arXiv · 1705.10348

Equation of Motion for Estimation Fidelity of Monitored Oscillating Qubits

Humairah Bassa·Lajos Diósi·Thomas Konrad·Hermann Uys
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Abstract

We study the convergence properties of state estimates of an oscillating qubit being monitored by a sequence of \textit{discrete}, unsharp measurements. Our method derives a differential equation determining the evolution of the estimation fidelity from a single incremental step. When the oscillation frequency $Ω$ is precisely known, the estimation fidelity converges exponentially fast to unity. For imprecise knowledge of $Ω$ we derive the asypmtotic estimation fidelity.

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Humairah Bassa, Lajos Diósi, Thomas Konrad, Hermann Uys. 2017-05-29. Equation of Motion for Estimation Fidelity of Monitored Oscillating Qubits. https://doi.org/10.1016/j.physleta.2017.05.013

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