Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Measurement of Temporal Correlations of the Overhauser Field in a Double Quantum Dot
AU - Reilly, D. J.
AU - Taylor, J M
AU - Laird, E. A.
AU - Petta, J R
AU - Marcus, C M
AU - Hanson, M P
AU - Gossard, A C
PY - 2008/12/1
Y1 - 2008/12/1
N2 - In quantum dots made from materials with nonzero nuclear spins, hyperfine coupling creates a fluctuating effective Zeeman field (Overhauser field) felt by electrons, which can be a dominant source of spin qubit decoherence. We characterize the spectral properties of the fluctuating Overhauser field in a GaAs double quantum dot by measuring correlation functions and power spectra of the rate of singlet-triplet mixing of two separated electrons. Away from zero field, spectral weight is concentrated below 10 Hz, with ∼1/f2 dependence on frequency f. This is consistent with a model of nuclear spin diffusion, and indicates that decoherence can be largely suppressed by echo techniques.
AB - In quantum dots made from materials with nonzero nuclear spins, hyperfine coupling creates a fluctuating effective Zeeman field (Overhauser field) felt by electrons, which can be a dominant source of spin qubit decoherence. We characterize the spectral properties of the fluctuating Overhauser field in a GaAs double quantum dot by measuring correlation functions and power spectra of the rate of singlet-triplet mixing of two separated electrons. Away from zero field, spectral weight is concentrated below 10 Hz, with ∼1/f2 dependence on frequency f. This is consistent with a model of nuclear spin diffusion, and indicates that decoherence can be largely suppressed by echo techniques.
KW - cond-mat.mes-hall,cond-mat.stat-mech
U2 - 10.1103/PhysRevLett.101.236803
DO - 10.1103/PhysRevLett.101.236803
M3 - Journal article
VL - 101
JO - Physical review letters
JF - Physical review letters
SN - 0031-9007
IS - 23
M1 - 236803
ER -