Work package 4 – Validation and Metrology

In this final work package, is where everything comes together. Based on the different materials and integration technologies that will be developed throughout the project, the most promising directions will be put together and validated in a final prototype device that demonstrates that it is possible to integrate both a CQPS current standard (for disseminating the Ampere) and a Josephson Voltage standard (for disseminating the Volt) in the same cryogenic measurement system. If possible, this would deliver a step change in electrical metrology as other units, such as resistance and impedance standards, could then also be derived from these two quantum standards. Integrated into a compact and easy to use measurement system this would unlock dissemination of all electrical units directly at end users, shortening the very long traceability chains to national metrology institutes and their primary electrical standards, thus significantly improving the quality of electronic measurement that underpins modern life.

Left: Some of the validation work carried out also includes understanding the coherence of phase slip processes, which can be studied using a so-called charge quantum interference device (CQUID, bottom), the dual counterpart to the superconducting quantum interference device (SQUID, top). (© RHUL/Anastasia Astafieva). Right: Scanning electron micrograph of multiple CQUID devices on a silicon chip (© RHUL).