论文标题
直接访问石墨烯中的螺旋钻重组
Direct Access to Auger recombination in Graphene
论文作者
论文摘要
螺旋钻散射通道对于描述和理解石墨烯中的非平衡荷载载体动力学至关重要。虽然撞击激发增加了传统带中的载体数量，并且已经通过实验观察到，但直接访问其反向过程，螺旋螺旋体重组迄今难以捉摸。在这里，我们通过将新型设置应用于超快时间分辨的光电子动量显微镜来解决这个问题。我们的方法使在线性分散狄拉克锥体内的所有能量和平面动力学方面同时访问载体动力学。因此，我们通过识别瞬时能量和动量依赖性种群远高于激发能量的瞬时能量和动量依赖性人群来直接证明在低10 fs时间尺度上重组的直接证据。我们将结果与狄拉克锥体中散射过程的模型计算进行比较，以支持我们的实验发现。
Auger scattering channels are of fundamental importance to describe and understand the non-equilibrium charge carrier dynamics in graphene. While impact excitation increases the number of carriers in the conduction band and has been observed experimentally, direct access to its inverse process, Auger recombination, has so far been elusive. Here, we tackle this problem by applying our novel setup for ultrafast time-resolved photoelectron momentum microscopy. Our approach gives simultaneous access to charge carrier dynamics at all energies and in-plane momenta within the linearly dispersive Dirac cones. We thus provide direct evidence for Auger recombination on a sub-10~fs timescale by identifying transient energy- and momentum-dependent populations far above the excitation energy. We compare our results with model calculations of scattering processes in the Dirac cone to support our experimental findings.
