KTaO₃-Based Supercurrent Diode

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Electronics

Background:

• The supercurrent diode effect (SDE) is crucial for dissipationless electronics and quantum circuits.
• Achieving SDE necessitates breaking time-reversal and inversion symmetry in superconducting devices.

Purpose of the Study:

• To engineer and demonstrate SDE in reconfigurable superconducting weak links at the LaAlO3/KTO interface.
• To investigate the tunability of SDE polarity and rectification efficiency.
• To understand the underlying physical mechanisms of SDE in this system.

Main Methods:

• Utilized conductive atomic force microscope (c-AFM) lithography to pattern nanoscale weak links.
• Fabricated devices at the LaAlO3/KTO interface.
• Employed modest out-of-plane magnetic fields to induce and control SDE.
• Performed time-dependent Ginzburg-Landau simulations.

Main Results:

• Successfully realized SDE in engineered LaAlO3/KTO weak links.
• Demonstrated reversible SDE polarity by altering weak link geometry.
• Achieved rectification efficiencies up to 13% under optimal magnetic fields.
• Simulations attributed SDE to asymmetric vortex motion in the engineered geometry.

Conclusions:

• The LaAlO3/KTO interface provides a versatile platform for SDE.
• Engineered nanoscale weak links offer precise control over SDE.
• This work lays the foundation for novel quantum circuit elements based on vortex dynamics.