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arXiv · 1608.02983

Individual band with higher Chern numbers in double perovskite {001} monolayers

A. M. Cook
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Abstract

We show a tight-binding model for double perovskite monolayers grown in the {001} crystallographic direction can exhibit higher Chern numbers for the lowest band of the model dispersion in the absence of an applied magnetic field, including $\pm2$, $\pm4$, $\pm6$, and $\pm8$, for model parameters and terms relevant to Sr$_2$CrWO$_6$ (SCWO). We further show it is possible to tune between these different topological phases by applying a weak in-plane magnetic field. These results may be important for experimentally realizing exotic band topologies -- and even quantum anomalous Hall insulators with higher Chern numbers -- based on this physics.

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A. M. Cook. 2016-11-24. Individual band with higher Chern numbers in double perovskite {001} monolayers. https://doi.org/10.1103/physrevb.94.205135

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