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Hysteretic resistance spikes in quantum Hall ferromagnets without domains

Henrique J. P. Freire·J. Carlos Egues
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Abstract

We use spin-density-functional theory to study recently reported hysteretic magnetoresistance ρ_{xx} spikes in Mn-based 2D electron gases [Jaroszyński et al. Phys. Rev. Lett. (2002)]. We find hysteresis loops in our calculated Landau fan diagrams and total energies signaling quantum-Hall-ferromagnet phase transitions. Spin-dependent exchange-correlation effects are crucial to stabilize the relevant magnetic phases arising from distinct symmetry-broken excited- and ground-state solutions of the Kohn-Sham equations. Besides hysteretic spikes in ρ_{xx}, we predict hysteretic dips in the Hall resistance ρ_{xy}. Our theory, without domain walls, satisfactorily explains the recent data.

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Henrique J. P. Freire, J. Carlos Egues. 2007-07-12. Hysteretic resistance spikes in quantum Hall ferromagnets without domains. https://doi.org/10.1103/physrevlett.99.026801

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