Coherence in logical quantum channels

• Published in: New journal of physics Vol. 22; no. 7; pp. 73066 - 73135
• Main Authors: Iverson, Joseph K, Preskill, John
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.07.2020
• Subjects: Circuits; Coherence; coherent noise; Decoding; Depolarization; Error analysis; Error correction; Error correction & detection; Fault tolerance; Noise; Physics; Quantum computing; quantum error correcting codes; Qubits (quantum computing); Rotation; surface code; toric code

We study the effectiveness of quantum error correction against coherent noise. Coherent errors (for example, unitary noise) can interfere constructively, so that in some cases the average infidelity of a quantum circuit subjected to coherent errors may increase quadratically with the circuit size; i...