Nonthermal and purely electronic resistive switching in a Mott memory

Mott insulator to metal transitions under an electric field are currently the subject of numerous fundamental and applied studies. This puzzling effect, which involves nontrivial out-of-equilibrium effects in correlated systems, is indeed at play in the operation of a new class of electronic memories, the ``Mott memories.'' However, the combined electronic and thermal effects are difficult to disentangle in Mott insulators undergoing such transitions. We report here a comparison between the properties under an electric field of a canonical Mott insulator and a model built on a realistic two-dimensional resistor network able to capture both thermal effects and electronic transitions. This comparison made specifically on the family of narrow gap Mott insulators AM₄Q₈, (A=Ga or Ge; M = V, Nb or Ta; and Q=S or Se) unambiguously establishes that the resistive transition experimentally observed under an electric field arises from a purely electronic mechanism.