Print Email Facebook Twitter Gate fidelity and coherence of an electron spin in an Si/SiGe quantum dot with micromagnet Title Gate fidelity and coherence of an electron spin in an Si/SiGe quantum dot with micromagnet Author Kawakami, E. (TU Delft QCD/Vandersypen Lab; TU Delft QN/Quantum Transport; TU Delft QuTech; Kavli institute of nanoscience Delft) Jullien, T.M.J. (TU Delft QN/Quantum Transport; TU Delft QuTech; Kavli institute of nanoscience Delft) Scarlino, P. (TU Delft QCD/Vandersypen Lab; TU Delft QuTech; Kavli institute of nanoscience Delft) Ward, Daniel R. (University of Wisconsin-Madison) Savage, Donald E. (University of Wisconsin-Madison) Lagally, Max G. (University of Wisconsin-Madison) Dobrovitski, V.V. (Iowa State University) Friesen, Mark (University of Wisconsin-Madison) Coppersmith, Susan N. (University of Wisconsin-Madison) Eriksson, M.A. (University of Wisconsin-Madison) Vandersypen, L.M.K. (TU Delft QCD/Vandersypen Lab; TU Delft QN/Vandersypen Lab; TU Delft QuTech; Kavli institute of nanoscience Delft; Components Research) Faculty QuTech Date 2016-10-18 Abstract The gate fidelity and the coherence time of a quantum bit (qubit) are important benchmarks for quantum computation. We construct a qubit using a single electron spin in an Si/SiGe quantum dot and control it electrically via an artificial spin-orbit field from a micromagnet. We measure an average single-qubit gate fidelity of ∼99% using randomized benchmarking, which is consistent with dephasing from the slowly evolving nuclear spins in the substrate. The coherence time measured using dynamical decoupling extends up to ∼400 μs for 128 decoupling pulses, with no sign of saturation. We find evidence that the coherence time is limited by noise in the 10-kHz to 1-MHz range, possibly because charge noise affects the spin via the micromagnet gradient. This work shows that an electron spin in an Si/SiGe quantum dot is a good candidate for quantum information processing as well as for a quantum memory, even without isotopic purification. Subject Dynamical decouplingElectron spinQubitRandomized benchmarkingSi/SiGe quantum dot To reference this document use: http://resolver.tudelft.nl/uuid:1746c5e8-c757-42b7-a127-e383272afcc9 DOI https://doi.org/10.1073/pnas.1603251113 Embargo date 2017-04-18 ISSN 0027-8424 Source Proceedings of the National Academy of Sciences of the United States of America, 113 (42), 11738-11743 Part of collection Institutional Repository Document type journal article Rights © 2016 E. Kawakami, T.M.J. Jullien, P. Scarlino, Daniel R. Ward, Donald E. Savage, Max G. Lagally, V.V. Dobrovitski, Mark Friesen, Susan N. Coppersmith, M.A. Eriksson, L.M.K. Vandersypen Files PDF 11738.full.pdf 1.07 MB Close viewer /islandora/object/uuid:1746c5e8-c757-42b7-a127-e383272afcc9/datastream/OBJ/view