论文标题
控制范德华异质结构中激子谷动力学的控制
Control of the exciton valley dynamics in van der Waals heterostructures
论文作者
论文摘要
带有过渡金属二进制基因元素单层的范德华异质结构中的激子谷动力学是由电子与激子中的孔之间的远距离交换相互作用驱动的。它耦合在相反的圆极化中活跃的状态，从而导致在单层平面中传播的激子的纵向反向分裂。在这里，我们从理论上研究了介电环境对远程交换相互作用的影响，并证明了六边形硝化硼中的封装如何修饰激子纵向横向分裂。由于远程交换相互作用，我们计算了激子自旋/谷化的极化弛豫，并证明单层环境的变化导致了激烈的，最多可增强了激子谷地极化寿命的五倍。
The exciton valley dynamics in van der Waals heterostructures with transition metal dichalcogenides monolayers is driven by the long-range exchange interaction between the electron and the hole in the exciton. It couples the states active in the opposite circular polarizations resulting in the longitudinal-transverse splitting of excitons propagating in the monolayer plane. Here we study theoretically the effect of the dielectric environment on the long-range exchange interaction and demonstrate how the encapsulation in the hexagonal boron nitride modifies the exciton longitudinal-transverse splitting. We calculate the exciton spin/valley polarization relaxation due to the long-range exchange interaction and demonstrate that the variation of the monolayer environment results in significant, up to five-fold, enhancement of the exciton valley polarization lifetime.
