Phase transitions in large N(c) heavy quark potentials
  We describe phase transitions in the heavy quark potential in planar gauge theories having wrapped D5-brane string duals. A new phase transition, previously unnoticed in these models, is driven by the source of a large dimension operator. Another transition, which has already been described in a previous paper, is driven by the presence of light dynamical flavors. Both transitions connect a Coulomb-like phase to a confining linear phase. 
F. Bigazzi, A.L. Cotrone, A. Paredes