Metal-to-insulator transition in an Anderson insulator with Kondo impurities

We report a voltage-controlled critical behavior observed in GaAs epitaxial structure containing dense array of ErAs nanoparticles. When fabricated with metal electrodes, the displays voltage- and temperature-dependent metal-to-insulator transition strong hysteresis current versus voltage temperature characteristics, temperatures as high 77 K. Furthermore, we diverging rms deviation electrical conductance respect to bias voltage, which further supports existence phase transition. The insulating is governed by Efros-Shklovskii variable range hopping, reduces beyond instrument limits drops toward zero; supporting it an Anderson insulator. metallic minimum at behaving similarly that single quantum dot due Kondo resonance, then increases continues drop. colossal magnetoresistance under weak magnetic field K while does not. And can be induced showing discontinuity, similar voltage. propose explained concept insulator impurities.