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arXiv · 1912.11505

Joint measurement of time-frequency entanglement via sum frequency generation

Han Liu·Amr S. Helmy
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Abstract

We propose, analyze, and evaluate a technique for the joint measurement of time-frequency entanglement between two photons. In particular, we show that the frequency sum and time difference of two photons could be simultaneously measured through the sum-frequency generation process, without measuring the time or frequency of each individual photon. We demonstrate the usefulness of this technique by using it to design a time-frequency entanglement based continuous variable superdense coding and a quantum illumination protocol. Performance analysis of these two protocols suggests that the joint measurement of strong time-frequency entanglement of non-classical photon pairs can significantly enhance the performance of joint-measurement based quantum communication and metrology protocols.

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Han Liu, Amr S. Helmy. 2019-12-24. Joint measurement of time-frequency entanglement via sum frequency generation. https://arxiv.org/abs/1912.11505

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