来源:本站 作者: 发布时间:2019-12-16
报告题目： Valleytronics in the moiré of 2D semiconductors
Van der Waals stacking of 2D materials into layered structures is a powerful approach towards designer quantum materials that can combine and extend the exotic properties of the building blocks. Ubiquitous to these vdW structures is the formation of moiré pattern due to the inevitable lattice mismatch and twisting between the layers. In monolayer building blocks like transition metal dichalcogenides (TMDs), carriers feature a valley degree of freedom, labelling the degenerate band edges at the Brillouin zone corners. Upon stacking such monolayers, the high symmetry and large momentum associated with the valleys give rise to sensitive dependence of interlayer process on the atomic registry between the layers, summarized as stacking and valley selection rules. And because of the stacking selection rules, new valley physics can emerge from the spatial variation of atomic registry in the moiré. We will show examples on the moiré engineering for valley-spintronic controls in semiconducting TMDs bilayers.