Sample-efficient quantum error mitigation via classical learning surrogates

The pursuit of practical quantum utility on near-term quantum processors is critically challenged by their inherent noise. Quantum error mitigation (QEM) techniques are leading solutions to improve computation fidelity with relatively low qubit-overhead, while full-scale quantum error correction remains a distant goal. However, QEM techniques incur substantial measurement overheads, especially when applied to families of quantum circuits parameterized by classical inputs. Focusing on zero-noise extrapolation (ZNE), a widely adopted QEM technique, here we devise the surrogate-enabled ZNE (S-ZNE), which leverages classical learning surrogates to perform ZNE entirely on the classical side. Unlike conventional ZNE, whose measurement cost scales linearly with the number of circuits, S-ZNE requires only constant measurement overhead for an entire family of quantum circuits, offering superior scalability. Theoretical analysis indicates that S-ZNE achieves accuracy comparable to conventional ZNE in many practical scenarios, and numerical experiments on up to 100-qubit ground-state energy and quantum metrology tasks confirm its effectiveness. Our approach provides a template that can be effectively extended to other quantum error mitigation protocols, opening a promising path toward scalable error mitigation. Quantum processors face significant challenges from inherent noise, limiting their practical utility. Here, the authors introduce surrogate-enabled zero-noise extrapolation (S-ZNE), a novel quantum error mitigation technique that uses classical learning surrogates to reduce measurement overhead, achieving scalable error mitigation with accuracy comparable to conventional methods, thus enhancing quantum computation fidelity.

Source: https://www.nature.com/articles/s42005-026-02827-w. 8 Sync News only summarizes and links out; content copyright belongs to the authors and original sources.