Above-Threshold Ionization And High-Order Harmonic Generation

In recent years,as the development of high intensity laser technology,researches on intense laser interaction with atoms has been a hot field topic.With sufficient intense laser field,aseries of new phenomena would ocuur,such as multiphoton ionization,above threshold onization(ATI) , tunnel ionization(TI) , stable ionization(SI)and so on.on the other hand,after ionization,electrons,under the interaction of the vicinity of the nucleus and recombine to the groud state.Subsequently a photon of high energy may be emitted.This is high-order harmonic generation(HHG).ATI is the first nonlinear effects which can't be explained perturbation theory,and HHG became a more active content because of its potential prospects for the application. They closly retated strong field physical phenomena.This thesis is divided into the following parts: reviewed the theory and research methods of ATI and HHG; Given electric dipole approximation of the Schrodinger equation, with the specific forms, and described in detail This paper used in the Crank-Nicholson numerical integration methods; Comments the main research results of ATI and HHG; Numerical calculation,got the harmonic spectrum and ionization rate at the same frequency and different laser intensity; Analysise and comparaed with a representative literature, consistent with the results obtained.