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arXiv · 1205.4565

Breakdown of the Korringa Law of Nuclear Spin Relaxation in Metallic GaAs

D. Kölbl·D. M. Zumbühl·A. Fuhrer·G. Salis·S. F. Alvarado
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Abstract

We present nuclear spin relaxation measurements in GaAs epilayers using a new pump-probe technique in all-electrical, lateral spin-valve devices. The measured T1 times agree very well with NMR data available for T > 1 K. However, the nuclear spin relaxation rate clearly deviates from the well-established Korringa law expected in metallic samples and follows a sub-linear temperature dependence 1/T1 ~ T^0.6 for 0.1 K < T < 10 K. Further, we investigate nuclear spin inhomogeneities.

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D. Kölbl, D. M. Zumbühl, A. Fuhrer, G. Salis, S. F. Alvarado. 2012-05-21. Breakdown of the Korringa Law of Nuclear Spin Relaxation in Metallic GaAs. https://doi.org/10.1103/physrevlett.109.086601

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