Electron dynamics of ultrafast energytransfer processes among quantum dots induced by long range electron correlation

近年来，由远程电子相关介导的原子和分子簇中的超快能量传递过程成为理论和实验学家关注的焦点。原子间库仑衰变（ICD）是这类衰变的第一个过程，其中电子激发的分子阳离子松弛到基态，而邻近的分子被电离。从那时起，在经典的原子和分子系统中研究了许多ICD的变体。2011年，我发表了一篇关于量子点（QDs）中的ICD过程的文章，开始对这些技术相关半导体材料的上述能量转移过程进行研究。在这个新方法（也是这个项目的基础）中，根据有效质量近似（EMA）在量子点的模型势中进行了高度相关的电子动力学计算。由于模型势的存在，结果对不同类型的量子点具有高度的通用性。我通过使用电子动力学计算长距离能量传递过程（如ICD）来进一步区分自己。为此，我使用了高度相关的多构型时变哈特里（MCTDH）方法的反对称修正，该方法提供了在包括连续体在内的完整构型空间中定义的波函数的详细知识。它还允许自然地采用光脉冲和散射电子。因此，整个过程对于量子点中ICD及相关现象的预测是最理想的。在这个项目中，我试图扩展现有的方法组合，这样就可以在实验上可行的各种量子点阵列中对电子和能量转移过程进行快速、灵活和结合的预测。为此，该模型将与声子和激子的动力学处理相结合，并进一步推广到各种实际的量子点几何。将测试不同形式和强度的电场对能量传递过程的光学控制。量子点中相关电子的数量将依次增加，这就需要从MCTDH过渡到更有效的电子动力学方法，可能是基于高斯的方法。由此奠定了在现实的量子点阵列（以及原子和分子）中进行超快、远程电子和能量转移过程的一般电子动力学处理的基石。预期的结果将进一步促进这些过程的技术应用，即用于产生慢电子的原子间库伦电子捕获（ICEC）和用于红外光电探测器的ICD。

Since a couple of years ultrafast energy transfer processes in clusters of atoms and molecules mediated by long-range electron correlation came into the focus of theoreticians and experimentalists. As a first process of such kind the interatomic Coulombic decay (ICD) was discovered, in which an electronically excited molecular cation relaxes into its ground state, while a neighboring molecule is ionized. Since then many variants of ICD were investigated in classical atomic and molecular systems. With a publication on the ICD process in quantum dots (QDs) in 2011 I started to establish the research on the aforementioned energy transfer processes for these technologically relevant semiconductor materials. In the novel methodology, on which also this project is based, highly correlated electron dynamics calculations are performed in model potentials for QDs according to the effective mass approximation (EMA). Due to the model potentials the results have a high degree of generality for different sorts of QDs. I further distinguish myself by using electron dynamics for calculations on a long-distance energy transfer processes as ICD. To do so I use an antisymmetric modification of the highly correlated multi-configuration time-dependent Hartree- (MCTDH) method that offers detailed knowledge of the wave function defined in the complete configuration space including the continuum. It furthermore allows for the natural adoption of optical pulses and scattering electrons. Therefore the whole procedure is optimal for the prediction of ICD and related phenomena in QDs.In this project I seek to extend the existing portfolio of methods in such a way that it becomes possible to make quick, flexible and binding predictions on electron and energy transfer processes in experimentally feasible arrays of various kinds of QDs. For this purpose the model will be combined with a dynamical treatment of phonons and excitons and furthermore generalized to the whole variety of realistic QD geometries. Electric fields of different form and strength for the optical control of energy transfer processes will be tested. The number of correlated electrons in the QDs will successively increase, requiring a transition from MCTDH to more efficient, presumably Gaussian-based methods for electron dynamics. With that the corner stone for a general electron dynamical treatment of ultrafast, long-range electron and energy transfer processes in realistic arrays of QDs - and moreover atoms and molecules - is placed. The expected results will furthermore serve to motivate technological use of the processes, i.e. the interatomic Coulombic electron capture (ICEC) for the generation of slow electrons and ICD for infrared photodetectors.