Towards a Bose-Glass of ultracold atoms in a disordered crystal of light
  Starting from one-dimensional Mott Insulators, we use a bichromatic optical lattice to add controlled disorder to an ideal optical crystal where bosonic atoms are pinned by repulsive interactions. Increasing disorder, we observe a broadening of the Mott Insulator resonances and the transition to an insulating state with a flat density of excitations, suggesting the formation of a Bose-Glass. 
L. Fallani, J. E. Lye, V. Guarrera, C. Fort, M. Inguscio