Electric field induced Mott insulator to metal transition and electrical memory effects in thin films of classic Mott insulator V₂O₃

We present experimental study showing an isothermal electric field-induced first-order phase transition from Mott-insulator to the metallic state in the epitaxial thin film of V₂O₃ deposited on (222) Al₂O₃ substrate, in the temperature regime below its Mott transition temperature of 180 K. This isothermal electric field-induced transition is accompanied by interesting electro-thermal memory effect, which depends on the measurement paths followed in the electric field–temperature phase space.  This memory effect is robust, and thus it presents the possibility of the usage of V₂O₃ as a two-port tunable electrical switching device with low power consumption. Our preliminary investigation reveals a large electric field-induced resistive switching in polycrystalline V₂O₃/Si thin film even at room temperature. A generalized framework of disorder-influenced first-order phase transition in combination with a resistor network model has been used to explain the observed experimental features. These findings promise possibilities for Mott insulators to be used as highly energy-efficient switches in novel technologies such as neuromorphic computing.