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arXiv · 0709.0920

Dynamic Nuclear Polarization with Single Electron Spins

J. R. Petta·J. M. Taylor·A. C. Johnson·A. Yacoby·M. D. Lukin·C. M. Marcus·M. P. Hanson·A. C. Gossard
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Abstract

We polarize nuclear spins in a GaAs double quantum dot by controlling two-electron spin states near the anti-crossing of the singlet (S) and m_S=+1 triplet (T+) using pulsed gates. An initialized S state is cyclically brought into resonance with the T+ state, where hyperfine fields drive rapid rotations between S and T+, 'flipping' an electron spin and 'flopping' a nuclear spin. The resulting Overhauser field approaches 80 mT, in agreement with a simple rate-equation model. A self-limiting pulse sequence is developed that allows the steady-state nuclear polarization to be set using a gate voltage.

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J. R. Petta, J. M. Taylor, A. C. Johnson, A. Yacoby, M. D. Lukin, C. M. Marcus, M. P. Hanson, A. C. Gossard. 2007-09-07. Dynamic Nuclear Polarization with Single Electron Spins. https://doi.org/10.1103/physrevlett.100.067601

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