中文摘要：

研究了盘状势阱中二维玻色一爱因斯坦凝聚（BEC）的孤立波．在平均场理论下，由BEC所满足的Gross—Pitaevkii方程出发导出了二维BEC所满足的非线性Schr6dinger方程．从该方程出发，研究单组分常振幅二维BEC（单组分常振幅BEC）的调制不稳定性，得到了该系统相应的增长率．

英文摘要：

The solition wave in Bose-Einstein condensate with disk-shaped trap is investigated in this paper. Beyond the mean field, a two- dimensional nonlinear Schr6dinger equation is obtained. The modulational instability for this system is studied analytically, and the growth rate for it is given.