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Measuring quantum state overlaps of traveling optical fields

J. Clausen·M. Dakna·L. Knoll·D. -G. Welsch
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Abstract

We propose a detection scheme for measuring the overlap of the quantum state of a weakly excited traveling-field mode with a desired reference quantum state, by successive mixing the signal mode with modes prepared in coherent states and performing photon-number measurements in an array of beam splitters. To illustrate the scheme, we discuss the measurement of the quantum phase and the detection of Schrodinger-cat-like states.

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J. Clausen, M. Dakna, L. Knoll, D. -G. Welsch. 1999-10-07. Measuring quantum state overlaps of traveling optical fields. https://doi.org/10.1016/s0030-4018(99)00537-4

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