Population oscillation of the multicomponent spinor Bose-Einstein condensate induced by nonadiabatic transitions

The generation of the population oscillation of the multicomponent spinor Bose-Einstein condensate is demonstrated in this paper. We observe and examine the nonsynchronous decreasing processes of the magnetic fields generated between quadrupole coils and Ioffe coils during the switch-off of the quadrupole-Ioffe-configuration trap, which is considered to induce a nonadiabatic transition. Starting from the two-level Schroedinger equation, we have done some numerical fitting and derived an analytical expression identical to the results of Majorana and Zener, of which both results well match the experimental data.