Charge Quantum Interference Device
in: Nature Physics (2018)
The demonstration of coherent quantum phase slips (CQPS) in disordered superconductors has opened up a new route towards exploring the fundamental charge-phase duality in superconductors with the promise of devices with new functionalities and a robust quantum current standard based on CQPS. For CQPS, a barrier for phase slips carried by tunneling of magnetic fluxons is realised by a continuous superconducting wire and is the exact quantum mechanical dual to Cooper-pair tunneling through the insulating barrier of a Josephson junction. Here we demonstrate a device that integrates several CQPS junctions: the Charge Quantum Interference Device (CQUID). The CQUID becomes the exact dual to the well known superconducting quantum interference device (SQUID), and shows the experimental demonstration of the Aharonov-Casher effect in a superconducting system void of dielectric barriers.