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Rapid State-Reduction of Quantum Systems Using Feedback Control

Joshua Combes·Kurt Jacobs
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Abstract

We consider using Hamiltonian feedback control to increase the speed at which a continuous measurement purifies (reduces) the state of a quantum system, and thus to increase the speed of the preparation of pure states. For a measurement of an observable with N equispaced eigenvalues, we show that there exists a feedback algorithm which will speed up the rate of state-reduction by at least a factor of 2(N+1)/3.

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Joshua Combes, Kurt Jacobs. 2006-01-24. Rapid State-Reduction of Quantum Systems Using Feedback Control. https://doi.org/10.1103/physrevlett.96.010504

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