Supercurrent Diode: A Sensitive Symmetry Probe and Symmetry-Augmented Device

A supercurrent diode is a superconductor where electric current flows more easily in one direction than the other. This effect is closely tied to the symmetry of the superconducting state and has exciting applications in quantum computing. First, they provide evidence for unconventional quantum states that could lead to robust quantum bits (qubits), potentially extending the lifespan of quantum information. Our research on supercurrent diodes in iron-based superconductors has revealed special symmetries representative of these topological quantum states. Second, supercurrent diodes, akin to semiconductor diodes, offer practical applications in cryogenic electronics, which are crucial for controlling quantum computers at extremely low temperatures. By strategically designing the symmetry of superconducting heterostructures with multiferroic materials, our latest breakthrough involves a supercurrent diode that can withstand strong magnetic fields, meeting industrial standards for the first time. These advancements in supercurrent diode research and low-dimensional superconducting heterostructures hold significant implications for developing powerful quantum computers.