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arXiv · 2003.11470

Fault tolerant quantum data locking

Zixin Huang·Pieter Kok·Cosmo Lupo
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Abstract

Quantum data locking is a quantum communication primitive that allows the use of a short secret key to encrypt a much longer message. It guarantees information-theoretical security against an adversary with limited quantum memory. Here we present a quantum data locking protocol that employs pseudo-random circuits consisting of Clifford gates only, which are much easier to implement fault tolerantly than universal gates. We show that information can be encrypted into $n$-qubit code words using order $n - H_\mathrm{min}(\mathsf{X})$ secret bits, where $H_\mathrm{min}(\mathsf{X})$ is the min-entropy of the plain text, and a min-entropy smaller than $n$ accounts for information leakage to the adversary. As an application, we discuss an efficient method for encrypting the output of a quantum computer.

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Zixin Huang, Pieter Kok, Cosmo Lupo. 2020-03-25. Fault tolerant quantum data locking. https://doi.org/10.1103/physreva.103.052611

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