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arXiv · 0904.3745

Feedback Control Using Only Quantum Back-Action

Kurt Jacobs
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Abstract

The traditional approach to feedback control is to apply forces to a system by modifying the Hamiltonian. Here we show that quantum systems can be controlled without any Hamiltonian feedback, purely by exploiting the random quantum back-action of a continuous weak measurement. We demonstrate that, quite remarkably, the quantum back-action of such an adaptive measurement is just as effective at controlling quantum systems as traditional feedback.

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Kurt Jacobs. 2009-04-24. Feedback Control Using Only Quantum Back-Action. https://doi.org/10.1088/1367-2630%2F12%2F4%2F043005

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