Physical Review A

Joint measurement of photon-number sum and phase-difference operators in a two-mode field

X.-B. Zou, K. Pahlke, Wolfgang M. Mathis

Published Oct 14, 2003• 5 citations

Abstract

We present an experimental scheme that realizes joint measurement of photon-number sum and phase-difference operators on a two-mode field. The proposed scheme only involves linear optical elements and photon detectors with single-photon sensitivity. Furthermore, we demonstrate that such a measurement setup can be applied to generate two-mode N-photon entangled states from a pair of squeezed vacuum states. These N-photon entangled states are useful resources for quantum-information processing, high-precision frequency measurement, and quantum optical lithography.

DOI: 10.1103/physreva.68.043819

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