Demonstrating real-time and low-latency quantum error correction with superconducting qubits
- Laura Caune
- Luka Skoric
- Nick S. Blunt
- Archibald Ruban
- Jimmy McDaniel
- Joseph A. Valery
- Andrew D. Patterson
- Alexander V. Gramolin
- Joonas Majaniemi
- Kenton M. Barnes
- Tomasz Bialas
- Okan Buğdaycı
- Ophelia Crawford
- György P. Gehér
- Hari Krovi
- Elisha Matekole
- Canberk Topal
- Stefano Poletto
- Michael Bryant
- Kalan Snyder
- Neil I. Gillespie
- Glenn Jones
- Kauser Johar
- Earl T. Campbell
- Alexander D. Hill
2026-06-01
Quantum error correction will be essential for quantum computers to realise their full potential. As quantum computers advance towards demonstrating a universal fault-tolerant logical gate set, implementing scalable and low-latency real-time decoding will be crucial to avoid an exponential slowdown and maintain a fast logical clock rate. Here, we demonstrate low-latency feedback with a scalable FPGA decoder integrated into the control system of a superconducting quantum processor. We perform an 8-qubit stability experiment with up to 25 decoding rounds and a sub-microsecond mean decoding time per round, providing strong evidence that the backlog problem will be avoided when the decoder is operated as a streaming decoder on a superconducting hardware with the strictest speed requirements. We observe logical error suppression as the number of decoding rounds is increased. We also implement and time a fast-feedback experiment demonstrating a decoding response time of 9.6 μ s for a total of 9 measurement rounds.