Robust finite-temperature disordered Mott insulating phases in   inhomogeneous Fermi-Fermi mixtures with density and mass imbalance
  Ultracold mixtures of different atomic species have great promise for realizing novel many-body phenomena. In a binary mixture of femions with a large mass difference and repulsive interspecies interactions, a disordered Mott insulator phase can occur. This phase displays an incompressible total density, although the relative density remain compressible. We use strong-coupling and Monte Carlo calculations to show that this phase exists for a broad parameter region for ultracold gases confined in a harmonic trap on a three-dimensional optical lattice, for experimentally accessible values of the trap parameters. 
Anzi Hu, M. M. Ma\'ska, Charles W. Clark, and J. K. Freericks
cond-mat.quant-gas