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Direct measurement of the Wigner function by photon counting

K. Banaszek·C. Radzewicz·K. Wodkiewicz·J. S. Krasinski
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Abstract

We report a direct measurement of the Wigner function characterizing the quantum state of a light mode. The experimental scheme is based on the representation of the Wigner function as an expectation value of a displaced photon number parity operator. This allowed us to scan the phase space point-by-point, and obtain the complete Wigner function without using any numerical reconstruction algorithms.

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K. Banaszek, C. Radzewicz, K. Wodkiewicz, J. S. Krasinski. 1999-03-08. Direct measurement of the Wigner function by photon counting. https://doi.org/10.1103/physreva.60.674

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