Dynamic gap from holographic fermions in charged dilaton black branes
  We report a dynamical formation of a (Mott) gap from holographic fermions. By coupling a fermion field with dipole action to the charged dilaton black branes with a Lifshitz like IR geometry and $AdS_{4}$ boundary, we find that when the dipole interaction is large enough, spectral weight is transferred between bands, and beyond a critical dipole interaction, a gap emerges in the fermion density of states. The value of the gap becomes larger as the strength of the interaction keeps increasing. 
Jian-Pin Wu, Hua-Bi Zeng
hep-th gr-qc