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arXiv · 1202.3340

Switchable Quantum Anomalous Hall state in a strongly frustrated lattice magnet

Jörn W. F. Venderbos·Maria Daghofer·Jeroen van den Brink·Sanjeev Kumar
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Abstract

We establish that the interplay of itinerant fermions with localized magnetic moments on a checkerboard lattice leads to magnetic flux-phases. For weak itineracy the flux-phase is coplanar and the electronic dispersion takes the shape of graphene-like Dirac fermions. Stronger itineracy drives the formation of a non-coplanar, chiral flux-phase, in which the Dirac fermions acquire a topological mass that is proportional to a ferromagnetic spin polarization. Consequently the system self-organizes into a ferromagnetic Quantum Anomalous Hall state in which the direction of its dissipationless edge-currents can be switched by an applied magnetic field.

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Jörn W. F. Venderbos, Maria Daghofer, Jeroen van den Brink, Sanjeev Kumar. 2012-02-15. Switchable Quantum Anomalous Hall state in a strongly frustrated lattice magnet. https://doi.org/10.1103/physrevlett.109.166405

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