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arXiv · 1409.5747

Temporal Quantum-State Tomography of Narrowband Biphotons

Peng Chen·Chi Shu·Xianxin Guo·M. M. T. Loy·Shengwang Du
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Abstract

We describe and demonstrate a quantum state tomography for measuring the complex temporal waveform of narrowband biphotons. Through six sets of two-photon interference measurements projected in different polarization subspaces, we can construct the time-frequency entangled two-photon joint amplitude and phase functions in continuous-variable time domain. For the first time, we apply this technique to experimentally determine the temporal quantum states of narrowband biphotons generated from spontaneous four-wave mixing in cold atoms, and fully confirm the theoretical predictions.

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Peng Chen, Chi Shu, Xianxin Guo, M. M. T. Loy, Shengwang Du. 2014-09-19. Temporal Quantum-State Tomography of Narrowband Biphotons. https://doi.org/10.1103/physrevlett.114.010401

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