A Two-Species Exclusion Model With Open Boundaries: A use of q-deformed   algebra
  In this paper we study an one-dimensional two-species exclusion model with open boundaries. The model consists of two types of particles moving in opposite directions on an open lattice. Two adjacent particles swap their positions with rate p and at the same time they can return to their initial positions with rate q if they belong to the different types. Using the Matrix Product Ansatz (MPA) formalism, we obtain the exact phase diagram of this model in restricted regions of its parameter space. It turns out that the model has two distinct phases in each region. We also obtain the exact expressions for the current of particles in each phase. 
Farhad H Jafarpour