- m at . m es - h al l ] 2 4 A pr 1 99 7 Critical Behavior of Nuclear - Spin Diffusion in GaAs / AlGaAs Heterostructures near Landau Level Filling ν = 1
نویسنده
چکیده
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. PACS numbers: 73.20.Dx, 73.40.Hm, 65.40.+g Typeset using REVTEX
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