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arXiv · 0905.0114

Quantum feedback by discrete quantum non-demolition measurements: towards on-demand generation of photon-number states

I. Dotsenko·M. Mirrahimi·M. Brune·S. Haroche·J. -M. Raimond·P. Rouchon
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Abstract

We propose a quantum feedback scheme for the preparation and protection of photon number states of light trapped in a high-Q microwave cavity. A quantum non-demolition measurement of the cavity field provides information on the photon number distribution. The feedback loop is closed by injecting into the cavity a coherent pulse adjusted to increase the probability of the target photon number. The efficiency and reliability of the closed-loop state stabilization is assessed by quantum Monte-Carlo simulations. We show that, in realistic experimental conditions, Fock states are efficiently produced and protected against decoherence.

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I. Dotsenko, M. Mirrahimi, M. Brune, S. Haroche, J. -M. Raimond, P. Rouchon. 2009-05-01. Quantum feedback by discrete quantum non-demolition measurements: towards on-demand generation of photon-number states. https://doi.org/10.1103/physreva.80.013805

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