Vortex state in Bose-Fermi mixture with attraction between bosons and   fermions
  Vortex states in the mixture of ultracold atomic clouds of bosons and fermions are investigated using the effective Hamiltonian for the Bose subsystem. A stability of the Bose system in the case of attractive interaction between components is studied in the framework of variational Bose wave function and Thomas-Fermi approximation. It is shown that the critical number of bosons increases in the presence of the vortex. 
N.M. Chtchelkatchev, S.-T. Chui, V. N. Ryzhov