论文标题
Trion诱导的掺杂的MOS2单层的光致发光
Trion induced photoluminescence of a doped MoS2 monolayer
论文作者
论文摘要
我们证明，掺杂的MOS2单层光致发光（PL）光谱的温度和掺杂依赖性具有由Trion辐射衰变定义的几个特殊特征。虽然仅将零孔激子状态与光耦合，但也允许非零动量TRIONS的辐射重组。这导致了随着温度升高的变化，导致TRION光谱峰和发射光的红移不对称。最低的能量状态是黑暗的，这表现为PL强度的急剧非单调温度依赖性。我们的计算结合了单粒子状态的Dirac模型，其参数是从第一个原理计算获得的，以及在TAMM-Dancoff近似中的三粒子问题的直接解。数值结果通过一个简单的模型很好地捕获，该模型可为PL光谱的温度依赖性产生分析表达式。
We demonstrate that the temperature and doping dependencies of the photoluminescence (PL) spectra of a doped MoS2 monolayer have several peculiar characteristics defined by trion radiative decay. While only zero-momentum exciton states are coupled to light, radiative recombination of non-zero momentum trions is also allowed. This leads to an asymmetric broadening of the trion spectral peak and redshift of the emitted light with increasing temperature. The lowest energy trion state is dark, which is manifested by the sharply non-monotonic temperature dependence of the PL intensity. Our calculations combine the Dirac model for the single-particle states, the parameters for which are obtained from the first principle calculations, and the direct solution of the three-particle problem within the Tamm-Dancoff approximation. The numerical results are well captured by a simple model that yields analytical expressions for the temperature dependencies of the PL spectra.
