A Holographic Flat Band
  We describe a novel implementation of non-relativistic fermions in AdS/CFT by imposing Lorentz violating boundary conditions for a Dirac spinor in AdS4. The dual boundary theory is scale invariant and exhibits a number of interesting properties, including a dispersionless flat band of gapless excitations. 
Jo\~ao N. Laia and David Tong
hep-th cond-mat.str-el