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arXiv · cond-mat/9805240

Magnetic Anisotropy in Quantum Hall Ferromagnets

T. Jungwirth·S. P. Shukla·L. Smrcka·M. Shayegan·A. H. MacDonald
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Abstract

We show that the sign of magnetic anisotropy energy in quantum Hall ferromagnets is determined by a competition between electrostatic and exchange energies. Easy-axis ferromagnets tend to occur when Landau levels whose states have similar spatial profiles cross. We report measurements of integer QHE evolution with magnetic-field tilt. Reentrant behavior observed for the $ν= 4$ QHE at high tilt angles is attributed to easy-axis anisotropy. This interpretation is supported by a detailed calculation of the magnetic anisotropy energy.

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T. Jungwirth, S. P. Shukla, L. Smrcka, M. Shayegan, A. H. MacDonald. 1998-05-19. Magnetic Anisotropy in Quantum Hall Ferromagnets. https://doi.org/10.1103/physrevlett.81.2328

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