Quantum anomalous Hall phase in (001) double-perovskite monolayers via intersite spin-orbit coupling

张洪彬博士

胡树军

2014-07-25 15:00

知新楼C座1111报告厅

Using tight-binding models and first-principles calculations, we demonstrate the possibility to achieve a quantum anomalous Hall (QAH) phase on a two-dimensional square lattice, which can be realized in monolayers of double perovskites. We show that effective intersite spin-orbit coupling between e_gorbitals can be induced perturbatively, giving rise to a QAH state. Moreover, the effective spin-orbit coupling can be enhanced by octahedral rotations. Based on first-principles calculations, we propose that this type of QAH state could be realized in La₂MnIrO₆monolayers, with the size of the gap as large as 26 meV in the ideal case.We observe that the electronic structure is sensitive to structural distortions, and that an enhanced HubbardUtends to stabilize the nontrivial gap.

Dr. Hongbin Zhang (张洪彬) received his MS degree at Shandong University in 2006, and Ph.D. degree in 2009 at TU Dresden, Germany. He was a postdoctoral researcher at FZ Juelich, Germany from 2006 to 2009. Now he is working at the Department of Physics and Astronomy at Rutgers University as a postdoc. His research is focusing on studying the physical properties induced by spin-orbit coupling in magnetic materials using the first principles methods. More detailed information can be found on http://www.physics.rutgers.edu/~hzhang/.