Experimental quantum data locking

TL;DR

This paper demonstrates experimental quantum data locking, showing that a small secret key can secure exponentially large information, surpassing classical limits, with practical applications like secure photo transmission over lossy channels.

Contribution

The paper provides the first experimental realization of quantum data locking schemes, including a loss-tolerant version, highlighting their practical feasibility and advantages over classical encryption.

Findings

Unlocked information exceeds key size, violating classical proportionality

Successful secure transmission of a photo over a lossy channel

Experimental validation of quantum data locking schemes

Abstract

Classical correlation can be locked via quantum means--quantum data locking. With a short secret key, one can lock an exponentially large amount of information, in order to make it inaccessible to unauthorized users without the key. Quantum data locking presents a resource-efficient alternative to one-time pad encryption which requires a key no shorter than the message. We report experimental demonstrations of quantum data locking scheme originally proposed by DiVincenzo et al. [Phys. Rev. Lett. 92, 067902 (2004)] and a loss-tolerant scheme developed by Fawzi, Hayde, and Sen [J. ACM. 60, 44 (2013)]. We observe that the unlocked amount of information is larger than the key size in both experiments, exhibiting strong violation of the incremental proportionality property of classical information theory. As an application example, we show the successful transmission of a photo over a lossy channel with quantum data (un)locking and error correction.