Lateral Gating of 2D Electron Gas in Cross-Sectional LaAlO₃/SrTiO₃

2D electron gas at LaAlO₃/SrTiO₃ (LAO/STO) interfaces has emerged as an attractive platform for novel nanoelectronic devices. Control over the active functional interface by electrical or mechanical means in this regard is of special interest. A new means of electric-field control by lateral gating of the interface and modification of its electronic properties in cross-sectional samples that allows direct access to depth-resolved physical-property measurements is investigated. Local scanning probe measurements in conjunction with electrical characterization allow it to be established that field-driven reversible migration of oxygen vacancies is the origin of enhancement and suppression of electronic conductivity in LAO/STO. These results point to new possibilities of device property control in complex oxide heterostructures and thin films that contain highly conductive engineered interfaces.