Noise-Robustness for Delegated Quantum Computation in the Circuit Model

TL;DR

This paper improves the noise tolerance of verifiable delegated quantum computation protocols in the circuit model by introducing a protocol that interleaves computation and testing, ensuring security and robustness against noise and server deviations.

Contribution

It extends the circuit-based verifiable quantum computation framework to noisy settings with a higher noise-tolerance threshold using an interleaved computation-test protocol.

Findings

Higher noise-tolerance threshold achieved

Protocol maintains security against server deviations

Robustness demonstrated in noisy quantum devices

Abstract

Cloud-based quantum computing, coupled with the rapid progress in quantum algorithms, brings to the forefront the question of verifiability in delegated quantum computations. In the current landscape of noisy quantum devices, this question must be addressed alongside noise tolerance. In this work, we revisit the circuit-based framework for verifiable quantum computation introduced by Broadbent [Theory of Computing, 2018], and extend it to the setting of server-side noise. Our contribution is an improved upper bound on the noise-tolerance threshold, achieved through a protocol that interleaves computation and test rounds in an indistinguishable manner. This structure enables a concise security proof against arbitrary deviations by the server, while ensuring robustness to realistic noise.