[1] Univ Southampton, Sch Elect & Comp Sci, Next Generat Wireless, Southampton SO17 1BJ, England
[2] Viavi Solut Inc, Viavi Marconi Labs, Stevenage SG1 2AN, England
[3] Univ Oxford, Dept Mat, Oxford OX1 3PH, England
[4] Photonic Inc, Quantum Processors Fault Tolerance Team, Coquitlam, BC V3K 6T1, Canada
[5] Univ Arizona, Dept Elect & Comp Engn, Tucson, AZ 85721 USA
[6] Univ Oxford, Math Inst, Oxford OX2 6GG, England
[7] Univ Leeds, Sch Elect & Elect Engn, Leeds LS2 9JT, England
[8] Kings Coll London, Fac Nat Math & Engn Sci, Dept Engn, London WC2R 2LS, England
[9] New Jersey Inst Technol, Newark, NJ 07102 USA