Speaker
Ms
Ashley Cook
(University of Toronto)
Description
Spectacular experiments have demonstrated the controlled layer-by-layer growth of
oxide heterostructures. This leads to the exciting prospect
of tuning magnetism and topological states of correlated electrons in low dimensions. Here, we model
$\{111\}$-grown bilayers of spin-orbit coupled double perovskites such as Sr$_2$FeMoO$_6$, showing
that these buckled honeycomb materials act as half-metallic ferrimagnetic films. The combination
of inter-orbital hybridization and symmetry-allowed trigonal distortion leads to a rich phase diagram with
tunable magnetization directions, topological $C\!=\! \pm 1, \pm 2$ Chern bands, and a $C=\pm 2$ quantum anomalous Hall insulator regime.
An effective two-band model of Zeeman-split $j\!=\! 3/2$ states captures this emergence of $C=\pm 2$ band topology.
Author
Ms
Ashley Cook
(University of Toronto)
Co-author
Prof.
Arun Paramekanti
(University of Toronto, Canadian Institute for Advanced Research)
