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Photon Added Detection

A. M. Branczyk·Tobias J. Osborne·Alexei Gilchrist·T. C. Ralph
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Abstract

The production of conditional quantum states and quantum operations based on the result of measurement is now seen as a key tool in quantum information and metrology. We propose a new type of photon number detector. It functions non-deterministically, but when successful, it has high fidelity. The detector, which makes use of an n-photon auxiliary Fock state and high efficiency Homodyne detection, allows a tunable tradeoff between fidelity and probability. By sacrificing probability of operation, an excellent approximation to a photon number detector is achieved.

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A. M. Branczyk, Tobias J. Osborne, Alexei Gilchrist, T. C. Ralph. 2003-05-30. Photon Added Detection. https://doi.org/10.1103/physreva.68.043821

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