Experimental unconditionally secure bit commitment
Abstract
Bit commitment is a fundamental cryptographic task that guarantees a secure commitment between two mutually mistrustful parties and is a building block for many cryptographic primitives, including coin tossing, zero-knowledge proofs, oblivious transfer and secure two-party computation. Unconditionally secure bit commitment was thought to be impossible until recent theoretical protocols that combine quantum mechanics and relativity were shown to elude previous impossibility proofs. Here we implement such a bit commitment protocol. In the experiment, the committer performs quantum measurements using two quantum key distribution systems and the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. We show that, in each run of the experiment, a bit is successfully committed with less than 5.68*10^-2 cheating probability. Our result demonstrates unconditionally secure bit commitment and the experimental feasibility of relativistic quantum communication.
Cite
@article{arxiv.1306.4413,
title = {Experimental unconditionally secure bit commitment},
author = {Yang Liu and Yuan Cao and Marcos Curty and Sheng-Kai Liao and Jian Wang and Ke Cui and Yu-Huai Li and Ze-Hong Lin and Qi-Chao Sun and Dong-Dong Li and Hong-Fei Zhang and Yong Zhao and Cheng-Zhi Peng and Qiang Zhang and Adan Cabello and Jian-Wei Pan},
journal= {arXiv preprint arXiv:1306.4413},
year = {2015}
}
Comments
15 pages, 2 figures