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arXiv · 0712.3620

Rapid Measurement of Quantum Systems using Feedback Control

Joshua Combes·Howard M. Wiseman·Kurt Jacobs
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Abstract

We introduce a feedback control algorithm that increases the speed at which a measurement extracts information about a $d$-dimensional system by a factor that scales as $d^2$. Generalizing this algorithm, we apply it to a register of $n$ qubits and show an improvement O(n). We derive analytical bounds on the benefit provided by the feedback and perform simulations that confirm that this speedup is achieved.

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Joshua Combes, Howard M. Wiseman, Kurt Jacobs. 2008-04-29. Rapid Measurement of Quantum Systems using Feedback Control. https://doi.org/10.1103/physrevlett.100.160503

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