Dynamics of matter-wave solutions of Bose-Einstein condensates in a   homogeneous gravitational field
  We find a matter-wave solution of Bose-Einstein condensates trapped in a harmonic-oscillator potential and subjected to a homogeneous gravitational field, by means of the extended tanhfunction method. This solution has as special cases the bright and dark solitons. We investigate the dynamics and the kinematics of these solutions, and the role of gravity is sketched. It is shown that these solutions can be generated and manipulated by controlling the s-wave scattering length, without changing the strengths of the magnetic and gravitational fields. 
Etienne Wamba, Hermano Velten, Alidou Mohamadou, Timol\'eon C.   Kofan\'e and K. Porsezian
cond-mat.quant-gas astro-ph.EP gr-qc