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arXiv · 1910.09102

Direct temporal mode measurement for the characterization of temporally multiplexed high dimensional quantum entanglement in continuous variables

Nan Huo·Yuhong Liu·Jiamin Li·Liang Cui·Xin Chen·Rithwik Palivela·Tianqi Xie·Xiaoying Li·Z. Y. Ou
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Abstract

Field-orthogonal temporal mode analysis of optical fields is recently developed for a new framework of quantum information science. But so far, the exact profiles of the temporal modes are not known, which makes it difficult to achieve mode selection and de-multiplexing. Here, we report a novel method that measures directly the exact form of the temporal modes. This in turn enables us to make mode-orthogonal homodyne detection with mode-matched local oscillators. We apply the method to a pulse-pumped, specially engineered fiber parametric amplifier and demonstrate temporally multiplexed multi-dimensional quantum entanglement of continuous variables in telecom wavelength. The temporal mode characterization technique can be generalized to other pulse-excited systems to find their eigen modes for multiplexing in temporal domain.

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Nan Huo, Yuhong Liu, Jiamin Li, Liang Cui, Xin Chen, Rithwik Palivela, Tianqi Xie, Xiaoying Li, Z. Y. Ou. 2019-10-21. Direct temporal mode measurement for the characterization of temporally multiplexed high dimensional quantum entanglement in continuous variables. https://doi.org/10.1103/physrevlett.124.213603

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