Generation of Two-Flavor Vortex Atom Laser from a Five-State Medium
  Two-flavor atom laser in a vortex state is obtained and analyzed via electromagnetically induced transparency (EIT) technique in a five-level $M$ type system by using two probe lights with $\pm z$-directional orbital angular momentum $\pm l\hbar$, respectively. Together with the original transfer technique of quantum states from light to matter waves, the present result can be extended to generate continuous two-flavor vortex atom laser with non-classical atoms. 
Xiong-Jun Liu, Hui Jing, Xin Liu and Mo-Lin Ge