Quantum Computing Research Archive

Real-time quantum error correction beyond break-even

Nature paper from Yale reporting a real-time error-corrected bosonic qubit (GKP code in a superconducting microwave cavity) whose logical lifetime exceeds that of the best uncorrected mode in the same system by roughly a factor of two. The correction loop runs in real time with an ancilla transmon for syndrome extraction and feedback.

Why it matters: First clear demonstration that active error correction can extend coherence past break-even, the threshold at which QEC starts paying for itself rather than adding net noise.