Filled Landau levels in neutral quantum gases
  We consider the signatures of the Integer Quantum Hall Effect in a degenerate gas of electrically neutral atomic fermions. An effective magnetic field is achieved by applying two incident light beams with a high orbital angular momentum. We show how states corresponding to completely filled Landau levels are obtained and discuss various possibilities to measure the incompressible nature of the trapped two-dimensional gas 
P. Ohberg, G. Juzeliunas, J. Ruseckas and M. Fleischhauer