二维层状材料的量子器件输运模拟和少子问题

Nowadays, two-dimensional (2D) layered materials, such as graphene and transition metal dichalcogenides, have attracted a lot of attention due to their extraordinary electronic and optical properties. As the prototypes of MoS2 and WSe2 2D field effect transistor (FET) were successfully fabricated, it seems that the practical application of these 2D devices becomes highly achievable. Our proposal aims to perform a large-scale quantum transport simulation of this 2D FET at the atomic level. Based on the non-equilibrium Green's function (NEGF) method, the simulation will be carried out on different approximation levels, from semi-empirical tight-binding to first-principles calculations. We seek to reveal the impacts of strain, impurity and substrate material on the transport properties from the atomic point of view and provide a theoretical analysis for the design of next generation FET. Besides, by means of large-scale exact diagonalization method?the few-body problem in the 2D layered material quantum dot will be investigated for the correlation effects among electrons.

以石墨烯和过渡金属硫族化合物为代表的二维层状材料由于其优良的电学和光学性质，成为近年来的一个热门研究领域。MoS2、WSe2等二维场效应晶体管原型器件的研制成功，意味着这类二维器件向实用化跨出了实质性的一步。 本项目将在原子尺度上对此类二维器件做大规模量子输运模拟。以非平衡格林函数为基础，我们的计算将从半经验紧束缚到第一性原理逐步开展。从原子角度揭示应力、杂质、衬底材料等因素对输运性质的影响，为新一代场效应晶体管的设计提供理论分析。另外我们还将用大规模严格对角化方法研究二维层状材料量子点体系中的少子问题，揭示电子间的关联效应。