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Measuring the elements of the optical density matrix

K. L. Pregnell·D. T. Pegg
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Abstract

Most methods for experimentally reconstructing the quantum state of light involve determining a quasiprobability distribution such as the Wigner function. In this paper we present a scheme for measuring individual density matrix elements in the photon number state representation. Remarkably, the scheme is simple, involving two beam splitters and a reference field in a coherent state.

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K. L. Pregnell, D. T. Pegg. 2002-09-25. Measuring the elements of the optical density matrix. https://doi.org/10.1103/physreva.66.013810

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