计及两体和三体作用下的二维凝聚体中的孤子特性

摘要

使用多重尺度法，解析地研究计及粒子间两体和三体同时作用下二维凝聚体中孤子的特性．结果发现，当凝聚体粒子间两体作用为排斥、三体作用为吸引时，凝聚体内会产生暗孤子环，且随着三体吸引作用的减弱，暗孤子环中心峰的高度逐渐降低，并当三体吸引作用消失时暗孤子环演化为一个完美的二维暗孤子．当两体和三体作用均为排斥时，凝聚体中的暗孤子的宽度和幅度随着三体排斥作用的加强而减小，且当三体作用强度增加到与两体作用同一数量级时，凝聚体产生坍塌现象．%By using multiple-scale method, we study analytically the solitou characteristics of the two-dimensional condensates with two- and three-body interaction. The results show that a ring dark soliton can be found in the condensates when the two-body interaction is repulsive and three-body interaction is attractive. With the strength of the three-body interaction decreasing, the height of the center peak of the ring dark soliton decreases. When the three-body interaction vanishes, the ring dark soliton becomes a perfect dark soliton. If the two- and the three-body interaction are both repulsive, the width and the amplitude of the dark soliton decrease with the strength of the three-body interaction increasing. Especially, if the strength of the three-body interaction is large, which is on the order of that of the two-body interaction, the condensat collapse takes place.