论文标题
激子相互作用引起的旋转分裂$ _2 $单层
Exciton interaction induced spin splitting in MoS$_2$ monolayer
论文作者
论文摘要
通过在循环极化的CW激光器下以$ 13 $ K的价格泵送Mos $ _2 $单层，我们观察到激子的能量红移，这破坏了与旋转相反旋转的B激子之间的退化。能量分裂会随着激光功率达到多达$ 18 $ MEV的单调增加，而温度会降低。理论上可以通过同时考虑带段的带隙重生化来解释这种现象，从而产生了红移和激子 - 外激体库仑交换相互作用，该相互作用负责旋转依赖性分裂。我们的结果提供了一个简单的方案，可以控制Mos $ _2 $单层中的山谷自由度，并提供了一种可访问的方法，用于调查此类材料中多体激子激子相互作用。
By pumping nonresonantly a MoS$_2$ monolayer at $13$ K under a circularly polarized cw laser, we observe exciton energy redshifts that break the degeneracy between B excitons with opposite spin. The energy splitting increases monotonically with the laser power reaching as much as $18$ meV, while it diminishes with the temperature. The phenomenon can be explained theoretically by considering simultaneously the bandgap renormalization which gives rise to the redshift and exciton-exciton Coulomb exchange interaction which is responsible for the spin-dependent splitting. Our results offer a simple scheme to control the valley degree of freedom in MoS$_2$ monolayer and provide an accessible method in investigating many-body exciton exciton interaction in such materials.
