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Spin polarization contrast observed in GaAs by force-detected nuclear magnetic resonance

Kent R. Thurber·Lee E. Harrell·Raul Fainchtein·Doran D. Smith
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Abstract

We applied the recently developed technique of force-detected nuclear magnetic resonance (NMR) to observe 71Ga, 69Ga, and 75As in GaAs. The nuclear spin-lattice relaxation time is 21$\pm$5 min for 69Ga at $\sim 5$ K and 4.6 Tesla. We have exploited this long relaxation time to first create and then observe spatially varying nuclear spin polarization within the sample, demonstrating a new form of contrast for magnetic resonance force microscopy (MRFM). Such nuclear spin contrast could be used to indirectly image electron spin polarization in GaAs-based spintronic devices.

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Kent R. Thurber, Lee E. Harrell, Raul Fainchtein, Doran D. Smith. 2002-01-14. Spin polarization contrast observed in GaAs by force-detected nuclear magnetic resonance. https://doi.org/10.1063/1.1458688

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