Interfering Josephson diode effect in Ta₂Pd₃Te₅ asymmetric edge interferometer.

Area of Science:

• Condensed Matter Physics
• Quantum Materials Science

Background:

• Topological insulators exhibit robust edge states with linear dispersions, making them promising for novel electronic applications.
• The Josephson diode effect (JDE) is a crucial phenomenon for realizing non-dissipative superconducting electronics.

Purpose of the Study:

• To engineer an asymmetric superconducting-proximitized edge interferometer on a topological insulator.
• To investigate and enhance the Josephson diode effect (JDE) in such a system.

Main Methods:

• Fabrication of a superconducting-proximitized edge interferometer on the topological insulator Ta₂Pd₃Te₅ with asymmetric edges.
• Experimental confirmation of the second-order harmonic in the current-phase relation via half-integer Shapiro steps.
• Analysis of antisymmetric second harmonic transport to confirm interferometer asymmetry and JDE polarity.

Main Results:

• Achieved a highly efficient interfering Josephson diode effect (JDE) with up to 73% efficiency.
• Demonstrated ultra-low switching power for JDE, around the picowatt level.
• Experimentally verified the second-order harmonic in the current-phase relation and antisymmetric second harmonic transport.

Conclusions:

• The engineered edge interferometer effectively enhances JDE performance.
• The findings offer a promising pathway for developing high-performance superconducting quantum devices.
• The study highlights the potential of topological insulators in advancing superconducting electronics.