KTaO3-based editable superconducting diode

TL;DR

This paper reports the first observation of a superconducting diode effect in LaAlO3/KTaO3 heterostructures, demonstrating reversible nanoscale editing of diode polarity and efficiency, paving the way for reconfigurable quantum circuits.

Contribution

It introduces a novel editable superconducting diode platform using oxide interfaces with tunable nonreciprocal transport properties.

Findings

Superconducting diode effect observed with >40% efficiency

Reversible nanoscale editing of diode polarity achieved

Multiple nonvolatile configurations demonstrated within a single device

Abstract

Superconducting diodes, which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction, are emerging as pivotal components for superconducting electronics. The development of editable superconducting diodes could unlock transformative applications, including dynamically reconfigurable quantum circuits that adapt to operational requirements. Here, we report the first observation of the superconducting diode effect (SDE) in LaAlO3/KTaO3 heterostructures, a two-dimensional oxide interface superconductor with exceptional tunability. We observe a strong SDE in Hall-bar (or strip-shaped) devices under perpendicular magnetic fields (< 15 Oe), with efficiencies above 40% and rectification signals exceeding 10 mV. Through conductive atomic force microscope lithography, we demonstrate reversible nanoscale editing of the SDE's polarity and efficiency by locally modifying the superconducting channel edges. This approach enables multiple nonvolatile configurations within a single device, realizing an editable superconducting diode. Our work establishes LAO/KTO as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities.