Coupled Bose-Einstein condensate: Collapse for attractive interaction
  We study the collapse in a coupled Bose-Einstein condensate of two types of bosons 1 and 2 under the action of a trap using the time-dependent Gross-Pitaevskii equation. The system may undergo collapse when one, two or three of the scattering lengths $a_{ij}$ for scattering of boson $i$ with $j$, $i,j = 1, 2 $, are negative representing an attractive interaction. Depending on the parameters of the problem a single or both components of the condensate may experience collapse. 
Sadhan K. Adhikari