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Photon Position Operator and Localization of Photons inside a Waveguide

Zhi-Yong Wang·Cai-Dong Xiong·Ole Keller
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Abstract

In this article, we show that in the level of quantum mechanics, a photon position operator with commuting components can be obtained in a more natural way; in the level of quantum field theory, the photon position operator corresponds to the center of the photon number. It is most interesting for us to show that, a photon inside a waveguide can be localized in the same sense that a massive particle can be localized in free space, and just as that it is impossible to localize a massive particle with a greater precision than its Compton wavelength, one can also arrival at a similar conclusion: it is impossible to localize a photon inside a waveguide with a greater precision than its equivalent Compton wavelength, which owing to evanescent-wave or photon-tunneling phenomena.

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Zhi-Yong Wang, Cai-Dong Xiong, Ole Keller. 2005-11-30. Photon Position Operator and Localization of Photons inside a Waveguide. https://arxiv.org/abs/quant-ph/0511270

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