超快非均质电子转移的优化控制研究(Ⅱ)

Laser pulse control of ultrafast heterogeneous electron transfer(Ⅱ)

本文用优化控制理论,以分子的基态作为目标态,考虑了在不同条件下,从二萘嵌苯到TiO2超快电子转移的动力学过程.发现在此目标态的作用下,电子经过一个电子激发-回落的过程从分子的基态激发到与半导体导带耦合的第一电子激发态,然后在给定目标态的作用下回落至电子基态,从而实现了较高的目标态产生率.由于二萘嵌苯的电子激发态与半导体导带能级间的强电子转移耦合,这一控制任务较电子激发态为目标态而言,更适合于实验研究.

With optimal control theory, we consider the case where the target state is located in the electronic ground state but shifted away from the minimum of the respective potential energy surface. In different conditions, the ultrafast heterogeneous electron transfer from perelyene to TiO2 is studied. It is found that the electron uses a pump - dump like scheme from the molecular ground state into the first excited electronic state, which coupled to the band continuum, and then back to the ground state with a target state given by the displaced vibrational ground state, therefore the high yield of target state is realized. Because of the strong coupling of the excited perylene state to the band continuum of TiO2 this control task seems more appropriate for a study in the experiment.