Coherent Operations and Screening in Multielectron Spin Qubits

TY - JOUR

T1 - Coherent Operations and Screening in Multielectron Spin Qubits

AU - Higginbotham, Andrew Patrick

AU - Kuemmeth, Ferdinand

AU - Hanson, M.P.

AU - Gossard, A.C.

AU - Marcus, Charles M.

N1 - preprint can be found at http://arxiv.org/abs/1306.2720

PY - 2014/1/14

Y1 - 2014/1/14

N2 - Multielectron spin qubits are demonstrated, and performance examined by comparing coherent exchange oscillations in coupled single-electron and multielectron quantum dots, measured in the same device. Fast (>1 GHz) exchange oscillations with a quality factor Q ∼ 15 are found for the multielectron case, compared to Q ∼ 2 for the single-electron case, the latter consistent with experiments in the literature. A model of dephasing that includes voltage and hyperfine noise is developed that is in good agreement with both single- and multielectron data, though in both cases additional exchange-independent dephasing is needed to obtain quantitative agreement across a broad parameter range.

AB - Multielectron spin qubits are demonstrated, and performance examined by comparing coherent exchange oscillations in coupled single-electron and multielectron quantum dots, measured in the same device. Fast (>1 GHz) exchange oscillations with a quality factor Q ∼ 15 are found for the multielectron case, compared to Q ∼ 2 for the single-electron case, the latter consistent with experiments in the literature. A model of dephasing that includes voltage and hyperfine noise is developed that is in good agreement with both single- and multielectron data, though in both cases additional exchange-independent dephasing is needed to obtain quantitative agreement across a broad parameter range.

U2 - 10.1103/PhysRevLett.112.026801

DO - 10.1103/PhysRevLett.112.026801

M3 - Journal article

C2 - 24484035

SN - 0031-9007

VL - 112

JO - Physical Review Letters

JF - Physical Review Letters

M1 - 026801

ER -