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Observation of the Preservation of the Two-Photon Coherence in Plasmon-assisted Transmission

Guo-Ping Guo·Xi-Feng Ren·Yun-Feng Huang·Chuan-Feng Li·Zhe-Yu Ou·Guang-Can Guo
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Abstract

We experimentally study two-photon coherence in plasmon-assisted transmission with a two-photon Mach-Zehnder (MZ) interferometer. Two collinear photons of identical or orthogonal polarization are simultaneously incident on one optically thick metal film, perforated with a periodic array of subwavelength holes. The de Broglie wavelength of plasmon-assisted transmitted photons is measured, which shows that two photons are re-eradiated by the plasmons and the quantum coherence of biphoton is preserved in the conversion process of transforming biphoton to plasmons and then back to biphoton.

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Guo-Ping Guo, Xi-Feng Ren, Yun-Feng Huang, Chuan-Feng Li, Zhe-Yu Ou, Guang-Can Guo. 2006-02-16. Observation of the Preservation of the Two-Photon Coherence in Plasmon-assisted Transmission. https://arxiv.org/abs/quant-ph/0512107

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