Nanoscale Superconducting Quantum Interference Devices Add Another Dimension

Over the past decade, nanoscale superconducting quantum interference devices (nanoSQUIDs) have rapidly risen from nowhere to forge a new sphere of applications of these macroscopic quantum devices. New fabrication techniques have enabled these advances. In this Perspective, we highlight another recent major development in this area-the demonstration of a three-axis nanoSQUID magnetometer, which enables the vector magnetization of a nanoscale magnetic particle to be measured in the presence of an applied magnetic field. We illustrate the technological demands and developments that have driven the development of nanoSQUIDs and make suggestions for future directions for applications.