Phase-Dependent Interactions of Bright Matter-Wave Solitons

Paul Dyke, Sidong Lei, S. E. Pollack +2 more

T. P. Billam

Guishu Chong, Wenhua Hai

A family of analytical solutions to a quasi one-dimensional time-dependent Gross–Pitaevskii equation with inverted parabolic potentials and time-varying nonlinear two-body interactions are presented, which simulate the dynamical evolutions of nonlinear matter-wave bright solitons. Synchronous behaviour between the variations of nonlinear interaction and compression or expansion of the solitons is demonstrated. For the case of higher order solitons, collision features are investigated. For travelling two solitons, different kinds of collisions are discussed for π and 0 phase difference between the two solitons at the collision point. Furthermore, a moving two-soliton 'bound' state is demonstrated. During the propagation, the solitons oscillate and collide many times.

Yongshan Cheng

The interaction of two coupled binary matter wave bright solitons is investigated by means of the variational approach in the presence of spatially varying nonlinearity. The effective potential characterizing the interaction between the two solitons is obtained. It is shown that the effective potential is composed of three parts, related to the spatially modulated nonlinearity, the external trapping potential and the interaction of the two coupled solitons. The spatially modulated nonlinearity induces a pseudo-potential and the solitons can be accelerated by the spatially modulated nonlinearity. The effect depends on the sign and value of the spatially modulated coefficient. The interaction of two coupled binary matter wave bright solitons is of short range, and may be attractive or repulsive depending on the sign of the interspecies interactions. Under the appropriate condition, the two coupled solitons can evolve stably and do not coalesce. The neighbouring binary Bose-Einstein condensates are also available as media to create symbiotic bright solitons. The validity of the theoretical predictions is verified by the numerical integration of the coupled Gross-Pitaevskii equations.

T. P. Billam

Simon L. Cornish, Nicholas G. Parker, A. Martin +4 more