Soliton Solutions and Collisions for the Multicomponent Gross-Pitaevskii Equation in Spinor Bose-Einstein Condensates

In this paper, we investigate a five-component Gross-Pitaevskii equation, which is demonstrated to describe the dynamics of an F = 2 spinor Bose-Einstein condensate in one dimension. By employing the Hirota method with an auxiliary function, we obtain the explicit bright one- and two-soliton solutions for the equation via symbolic computation. With the choice of polarization parameter and spin density, the one-soliton solutions are divided into four types: one-peak solitons in the ferromagnetic and cyclic states and one- and two-peak solitons in the polar states. For the former two, solitons share the similar shape of one peak in all components. Solitons in the polar states have the one- or two-peak profiles, and the separated distance between two peaks is inversely proportional to the value of polarization parameter. Based on the asymptotic analysis, we analyze the collisions between two solitons in the same and different states.