Oxide Nanoelectronics for Quantum Information

Electronic confinement at nanoscale dimensions remains a central means of science and technology.  I will describe a novel method for producing electronic nanostructures at the interface between two normally insulating oxides, LaAlO₃ and SrTiO₃.  Nanostructures with features as small as 2 nm--comparable to the mean spacing between electrons--are “written” using a conductive atomic force microscope (AFM) technique.  The oxide “canvases” are reconfigurable and can be erased and rewritten indefinitely.  A wide variety of device concepts have already been demonstrated, including nanowires, tunnel barriers, Fabry-Perot cavities, rectifying junctions, field-effect transistors, single-electron transistors, superconducting nanowires, quantum dots and nanoscale THz emitters and detectors. A major ongoing research effort, which I will highlight in this talk, involves the engineering of topological quantum phases, e.g., those which can support Majorana fermions, and solid-state quantum simulation of strongly correlated fermionic systems.