Resistance switching of the interfacial conductance in amorphous SrTiO3 heterostructures

Complex oxides have attracted a lot of interest recently as this class of material exhibits a plethora of remarkable properties. In particular, a great variety of properties is observed in the heterostructure composed of lanthanum aluminate (LaAlO3) and strontium titanate (SrTiO3). For instance, at the interface between the two insulating oxides LaAlO3 and SrTiO3 a high-mobility quasi-two-dimensional electron gas is formed if the thickness of LaAlO3 exceeds a critical value of 3 unit cells. At a thickness of 3 unit cells the interface remains insulating, however, an interface conductance can be induced by an electric field. It has previously been demonstrated that SrTiO3 heterostructures with amorphous LaAlO3 top layers can display interfacial conductivity with similar critical thickness dependence. Here, we report resistance switching of the interfacial conductance for SrTiO3 heterostructures with amorphous LaAlO3 top layers below the critical thickness in various controlled environments.