Progress Toward Quantum-Based Force Standard in KRISS

A quantum-based force standard project is in progress at Korea Research Institute of Standards and Science (KRISS). Since Choi et al. proposed the concept of generating discrete sub-piconewton magnetic force utilizing a superconducting microring, the experimental setup and device fabrication have been pursued. Using dynamic cantilever magnetometry, the magnetic moment of a single fluxoid quantum in an Nb micro ring was determined to be 5.8 fAm
²
in consistency with a theoretical prediction. For static force realization and measurement, two-fIber-optic interferometry was to minimize the drift of displacement signal by temperature change or over time.