Tunneling lifetime of trapped condensates
  Using the complex scaling transformation we calculate the tunneling lifetime of a condensate inside a magnetic/optical trap. We show that by varying the scattering length, the external potential acts like a 'selective membrane' which controls the direction of the flux of the cold atoms through the barriers and thereby controls the size of the stable condensate inside the trap. 
Nimrod Moiseyev and Lorenz S. Cederbaum