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Critical Behavior of Nuclear-Spin Diffusion in GaAs/AlGaAs Heterostructures near Landau Level Filling ν=1

V. Bayot·E. Grivei·J. -M. Beuken·S. Melinte·M. Shayegan
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Abstract

Thermal measurements on a GaAs/AlGaAs heterostructure reveal that the state of the confined two-dimensional electrons dramatically affects the nuclear-spin diffusion near Landau level filling factor ν=1. The experiments provide quantitative evidence that the sharp peak in the temperature dependence of heat capacity near ν=1 is due to an enhanced nuclear-spin diffusion from the GaAs quantum wells into the AlGaAs barriers. We discuss the physical origin of this enhancement in terms the possible Skyrme solid-liquid phase transition.

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V. Bayot, E. Grivei, J. -M. Beuken, S. Melinte, M. Shayegan. 1997-04-24. Critical Behavior of Nuclear-Spin Diffusion in GaAs/AlGaAs Heterostructures near Landau Level Filling ν=1. https://doi.org/10.1103/physrevlett.79.1718

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