Complex Envelope Soliton in Bose-Einstein Condensate with Time Dependent   Scattering Length
  We elaborate on a general method to find complex envelope solitons in a cigar shaped Bose-Einstein condensate in a trap. The procedure incorporates time dependent scattering length, oscillator frequency and loss/gain. A variety of time dependencies of the above parameters, akin to the ones occurring in the experiments can be tackled. 
Ayan Khan, Rajneesh Atre and Prasanta K. Panigrahi