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Nuclear spin ferromagnetic phase transition in an interacting 2D electron gas

Pascal Simon·Daniel Loss
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Abstract

Electrons in a two-dimensional semiconducting heterostructure interact with nuclear spins via the hyperfine interaction. Using a a Kondo lattice formulation of the electron-nuclear spin interaction, we show that the nuclear spin system within an interacting two-dimensional electron gas undergoes a ferromagnetic phase transition at finite temperatures. We find that electron-electron interactions and non-Fermi liquid behavior substantially enhance the nuclear spin Curie temperature into the $mK$ range with decreasing electron density.

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Pascal Simon, Daniel Loss. 2006-11-12. Nuclear spin ferromagnetic phase transition in an interacting 2D electron gas. https://doi.org/10.1103/physrevlett.98.156401

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