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arXiv · 1405.6251

Complete temporal characterization of a single photon

Zhongzhong Qin·Adarsh S. Prasad·Travis Brannan·Andrew MacRae·A. Lezama·A. I. Lvovsky
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Abstract

Precise information about the temporal mode of optical states is crucial for optimizing their interaction efficiency between themselves and/or with matter in various quantum communication devices. Here we propose and experimentally demonstrate a method of determining both the real and imaginary components of a single photon's temporal density matrix by measuring the autocorrelation function of the photocurrent from a balanced homodyne detector at multiple local oscillator frequencies. We test our method on single photons heralded from biphotons generated via four-wave mixing in an atomic vapor and obtain excellent agreement with theoretical predictions for several settings.

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Zhongzhong Qin, Adarsh S. Prasad, Travis Brannan, Andrew MacRae, A. Lezama, A. I. Lvovsky. 2014-05-24. Complete temporal characterization of a single photon. https://doi.org/10.1038/lsa.2015.71

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