Electrical domain writing and nanoscale potential modulation on LaVO3/SrTiO3

Abstract

The high-mobility 2 dimensional electron gases formed at the interfaces between certain insulating perovskite oxides have known to be a playground of exotic physical orders like superconductivity and ferromagnetism and their inter-coupling. There have been efforts to accomplish electronic confinement at such interfaces of oxide heterostructures through nano-structuring of the surface. In this paper, we report writing and erasing charge domains on such an oxide heterostructure LaVO3/SrTiO3 using a conductive AFM cantilever. We have patterned these domains in a periodic fashion in order to create artificial lattices on the surface. Through kelvin probe microscopy, electrostatic force microscopy, and conductivity mapping of such artificial lattices, we found that the domains not only trap charge carriers but also develop a controllable potential landscape on the surface which coincides with a modulation of local electrical conductivity. The ability to pattern such nanostructures reversibly offers unprecedented opportunities of realizing ultra-high storage density devices in high mobility oxide heterostructures.