Non-sequential Double Ionization Of Molecules In The Intense Laser Field

The intense laser field is applied to atoms and molecules, non-sequential double ionization (NSDI) phenomenon is found. In order to explain this novel physical phenomena, theoretical workers have made a lot of models. During these models, semiclassical rescattering model (SRM) and quantum S matrix model are especially typical. Experimental data show that two-electron correlation plays a very important role on the process of NSDI and SRM just takes two-electron correlation into account. Therefore, SRM can be served as an important theoretical model to study complex characteristics of atoms and molecules in the intense laser field.SRM is applied to research NSDI of molecules in the intense laser field and some results have been received in this article. This article is divided into six chapters: The first chapter describes some basic theories of the intense laser field, such as multi-photon ionization, above-threshold ionization, over-the-barrier ionization, etc; The second chapter describes the contents of SRM in detail; In chapter III, it is studied that laser intensity and wavelength of laser pulses have an effect on the process of hydrogen molecular NSDI. The results show that the impact of laser intensity on the process of NSDI when molecular orientation is parallel to the direction of electric field is bigger than that when molecular orientation is perpendicular to the direction of electric field. At the same time, we find that the effect of laser intensity and wavelength of laser pulses on the process of hydrogen molecular NSDI are similar; Taking into account internal complex factors of molecules, we find that molecular internuclear distance has an impact on the process of NSDI in chapter IV; In chapter V, we firstly introduce quantum S matrix theory, and then SRM and quantum S matrix model are compared. With classical and quantum aspects, we can do further study on the process of molecular NSDI in the intense laser field; The final chapter is a summary of this work.