Numerical Studies On CEPD Effect On Atomic And Molecular Photoionization Induced By Attosecond Pulses

In this dissertation, we studied the interaction between high intensity laser pulse and atoms or molecules, especially with great attention paid toward the CEPD(namely Carrier-Envelope Phase Difference) effect on atomic and molecular photoionization processes induced by attosecond pulses. We performed extensive computer simulations on the CEPD effect on photoionization of hydrogen atom by numerically solving the time-dependent Schrodinger equation. We obtained some reasonable results in photoionization of hydrogen atom, which may pave the way towards further investigation on molecular systems.In the first chapter we introduced the basic concepts and theories of interaction between ultrashort laser pulses and atoms and molecules. And we presented the research trend in this bloc in the world.In the second chapter we presented some frequently used terms and concepts associated with photoionization and photodissociation of molecular systems, such as hydrogen molecule, exposed to high intensity laser fields.In the third chapter we described the atomic units which are widely used in the study of ultrashort and ultrastrong laser pulse excitation of atoms or molecules. And we introduced the fourth-order Runge-Kutta algorithm which we deployed in our later calculations.In the fourth chapter we discussed a one-dimensional model of hydrogen atom for our numerical computation for its photoionization induced by attosecond duration laser pulses.Last chapter contains the results that we achieved through vast numerical experiments on the one-dimensional model hydrogen atom for photoionization probability. Some discussions and future direction for investigation were also presented.