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Quantum non-demolition measurement of photon-arrival using an atom-cavity system

Kunihiro Kojima·Akihisa Tomita
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Abstract

A simple and efficient quantum non-demolition measurement (QND) scheme is proposed in which the arrival of a signal photon is detected without affecting the qubit state. The proposed QND scheme functions even if the ancillary photon is replaced with weak light composed of vacuum and one-photon states. Although the detection scheme is designed for entanglement sharing applications, it is also suitable for general purification of a single photon state.

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Kunihiro Kojima, Akihisa Tomita. 2007-02-14. Quantum non-demolition measurement of photon-arrival using an atom-cavity system. https://arxiv.org/abs/quant-ph/0702138

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