Google Quantum AI Introduces Virtual Error Cancellation for Universal Logical Circuits

Google Quantum AI has developed Virtual Error Cancellation (VEC), a classical post-processing technique that significantly reduces logical errors in fault-tolerant quantum circuits. VEC uses a dual-decoder approach, combining a fast real-time decoder with a high-accuracy offline decoder, to reweight experimental outcomes and suppress logical error rates by over 1,600-fold. This method offers a more efficient alternative to previous error mitigation techniques, with a significantly lower sampling