Nanoscale electrostatic control of oxide interfaces.
We develop a robust and versatile platform to define nanostructures at oxide interfaces via patterned top gates. Using LaAlO3/SrTiO3 as a model system, we demonstrate controllable electrostatic confinement of electrons to nanoscale regions in the conducting interface. The excellent gate response, ultralow leakage currents, and long-term stability of these gates allow us to perform a variety of studies in different device geometries from room temperature down to 50 mK. Using a split-gate device we demonstrate the formation of a narrow conducting channel whose width can be controllably reduced via the application of appropriate gate voltages. We also show that a single narrow gate can be used to induce locally a superconducting to insulating transition. Furthermore, in the superconducting regime we see indications of a gate-voltage controlled Josephson effect.
Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Srijit
S
Goswami
Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Emre
E
Mulazimoglu
Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Lieven M K
LM
Vandersypen
Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Andrea D
AD
Caviglia
Oxide interfaces; nanoelectronics; split gates; superconducting weak link; top-gating