The Study Of Two-component BEC With Long-range Monopolar Interaction

The thesis analyzes the properties of two-component Bose-Einstein Condensates(BEC) with long-range monopolar interaction by means of exact numerical simulation and Thomas-Fermi Approximation respectively. The coupled Gross-Pitaevskii Equations(GP Equations)are obtained firstly. The effects of external trap potential, inter-component s-wave scattering, monopolar interaction,and particle numbers on the density of BEC is investigated. It is shown that the trap potential dramatically affects density profiles compared to the other three properties, and atoms with the small intra-component s-wave scattering length are squeezed out when the monopolar interaction of these atoms is not large enough. Effective zero interaction point, where the s-wave scattering repulsive interaction is neutralized by monopolar attractive interaction, is found..The thesis is arranged as follows:Chapter One reviews the history of BEC, and obtain generalizedcoupled GP Equations in detail;The effects of external trap potential, inter-component s-wave scattering, monopolar interaction,and particle numbers on the density of BEC is investigated by means of exact numerical simulation in Chapter Two;In Chapter Three, ground state density profiles are given with a numerical method under Thomas-Fermi Approximation;We summarize this thesis at last chapter, and give perspectives in GP Equation with fine structure.