Demonstration of Efficient Predictive Surrogates for Large-scale Quantum Processors

TL;DR

This paper introduces classical predictive surrogates that emulate large-scale quantum processors, significantly reducing measurement overhead and enabling efficient quantum simulations, thus broadening quantum computing applications.

Contribution

The authors propose and demonstrate two predictive surrogates that emulate quantum processor behavior with provable efficiency, reducing quantum resource requirements for large-scale simulations.

Findings

Surrogates emulate quantum processors with up to 20 qubits.

Measurement overhead is reduced by orders of magnitude.

Surrogates outperform conventional quantum-resource-intensive methods.

Abstract

The ongoing development of quantum processors is driving breakthroughs in scientific discovery. Despite this progress, the formidable cost of fabricating large-scale quantum processors means they will remain rare for the foreseeable future, limiting their widespread application. To address this bottleneck, we introduce the concept of predictive surrogates, which are classical learning models designed to emulate the mean-value behavior of a given quantum processor with provably computational efficiency. In particular, we propose two predictive surrogates that can substantially reduce the need for quantum processor access in diverse practical scenarios. To demonstrate their potential in advancing digital quantum simulation, we use these surrogates to emulate a quantum processor with up to 20 programmable superconducting qubits, enabling efficient pre-training of variational quantum eigensolvers for families of transverse-field Ising models and identification of non-equilibrium Floquet symmetry-protected topological phases. Experimental results reveal that the predictive surrogates not only reduce measurement overhead by orders of magnitude, but can also surpass the performance of conventional, quantum-resource-intensive approaches. Collectively, these findings establish predictive surrogates as a practical pathway to broadening the impact of advanced quantum processors.