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arXiv · cond-mat/9702193

Shape Deformation driven Structural Transitions in Quantum Hall Skyrmions

Madan Rao·Surajit Sengupta·R. Shankar
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Abstract

The Quantum Hall ground state away from $ν= 1$ can be described by a collection of interacting skyrmions. We show within the context of a nonlinear sigma model, that the classical ground state away from $ν= 1$ is a skyrmion crystal with a generalized Néel order. We show that as a function of filling $ν$, the skyrmion crystal undergoes a triangle to square to triangle transition at zero temperature. We argue that this structural transition, driven by a change in the shape of the individual skyrmions, is stable to thermal and quantum fluctuations and may be probed experimentally.

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Madan Rao, Surajit Sengupta, R. Shankar. 1997-02-21. Shape Deformation driven Structural Transitions in Quantum Hall Skyrmions. https://doi.org/10.1103/physrevlett.79.3998

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