基于瞬态吸收显微成像的不同基底上石墨烯的载流子弛豫动力学研究

石墨烯的最大特性之一是载流子的运动速度高达光速的1/300，其器件性能主要取决于载流子的散射和弛豫过程。因此研究石墨烯载流子的弛豫过程对于石墨烯未来的器件化应用有着非常重要的意义，同时也可了解材料中载流子弛豫的一般规律。已有的研究发现通过某些基底可以有效的改善石墨烯载流子行为的均一性，并保持其高迁移率的传输特性。我们认为可以通过设计和选择合适的基底来优化石墨烯载流子和基底的相互作用，改善石墨烯载流子行为的均一性，延缓石墨烯载流子的弛豫时间，从而保持石墨烯载流子特有的迁移率高的性质。本项目正是基于这一认识，提出利用瞬态吸收显微成像，研究不同基底上石墨烯的瞬态吸收显微图像和载流子的弛豫过程，并为石墨烯的器件化应用寻求到一种合适的基底。

One of the remarkable properties of graphene is its high charge carrier mobility, up to 1/300 of light speed. The performance of graphene-bansed device depends critically on the charge carrier scattering process and decay dynamics. Hence, it is very necessary and important to investigate the charge carrier decay dynamics for furture applications of graphene. And it will also help us understand the common rules in the charge carrier decay dynamics of materials. Previous studies found that some substrates could be used to effectively improve the uniformity of charge carrier dynamics and keep high charge carrier mobility significantly. We believe that by designing and selecting suitable substrate,the interaction between graphene and substrate can be optimized, which will improve the the uniformity of charge carrier dynamics, shorten the charge carrier decay time and help keep its remarkably high charge carrier mobility. In this proposal, we will investigate the uniformity of transient absorption microscopy images and charge carrier decay dynamics of graphene supported by different substrates via transient absorption microscopy. We are trying to find a suitable subtrate for graphene in future device application.