| Electron-electron correlation is a common phenomenon in the microscopic world.The non-sequential double ionization process in the intense laser field provides a simple model for studying the electronic correlation and became a frontier of the strong-field laser physics.In this paper,we study the non-sequential double ionization process in the intense laser field by a full quantum treatment in which the laser field and the atom are quantized.We obtain the quantized wave function of the double ionization process and the transition matrix of the double ionization process in the single mode laser field.The main research contents of this thesis are as follows:(1)The eigenwave function describing the two electron motions in a single mode laser field is obtained,and the transition matrix elements of atomic non-sequential double ionization are derived.The Hamiltonian is divided into two parts by the canonical transformation consisting of the Hamiltonian in the internal degree of freedomcH and the Hamiltonian in the external degree of freedomVH.The internal degree of freedom is independent of the laser field and is only related to the interaction between electrons.The wave function is the eigenstate of the Coulomb potential.The external degree of freedom describes that two electrons are affected by the laser field,which can be regarded as a quasi-particle moving in the laser field.And the corresponding Volkov state can be obtained by solving the Schr?dinger-like equation.The two partial wave functions are combined to obtain the final wave function,and the double ionization transition matrix elements are derived according to the scattering theory.(2)The Volkov state in the single-mode laser field is extended to the two-mode laser field.The wave function of the two-electron and the double-ionization transition matrix element in different two-mode field are obtained.The Volkov state of thetwo-electrons moving in the two mode laser field is obtained,and also the total wave function by the graphical technique of the generalized Bessel function.The variation of Volkov state in the two mode laser field with different polarizations is further discussed.Then we get the corresponding double ionization transition matrix elements.These work laid the foundation for the in-depth analysis of the double ionization of atoms and molecules in the laser field using the theory of full quantum. |
