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arXiv · 0804.4411

Experimental quantum tossing of a single coin

A. T. Nguyen·J. Frison·K. Phan Huy·S. Massar
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Abstract

The cryptographic protocol of coin tossing consists of two parties, Alice and Bob, that do not trust each other, but want to generate a random bit. If the parties use a classical communication channel and have unlimited computational resources, one of them can always cheat perfectly. Here we analyze in detail how the performance of a quantum coin tossing experiment should be compared to classical protocols, taking into account the inevitable experimental imperfections. We then report an all-optical fiber experiment in which a single coin is tossed whose randomness is higher than achievable by any classical protocol and present some easily realisable cheating strategies by Alice and Bob.

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A. T. Nguyen, J. Frison, K. Phan Huy, S. Massar. 2008-04-28. Experimental quantum tossing of a single coin. https://doi.org/10.1088/1367-2630%2F10%2F8%2F083037

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