A Self-Dual Bogomol'nyi Formulation of the Nonlinear Schr\"odinger   Equation
  We obtain a self-dual formulation of the conventional nonlinear Schr\"odinger equation (NLSE) in the 1+1 dimension by studying the dimensional reduction of the self-dual Chern-Simons nonlinear Schr\"odinger model (NLSM) in the 2+1 dimension. It is found that this self-dual formulation allows us to find not only the well-known soliton solutions from the Bogomol'nyi bound and the Galilean boost, but also other soliton solutions in the presence of the background sources. 
Phillial Oh and Chaiho Rim