European expertise in quantum metrology
Superconducting QUantum Interference Devices, or SQUIDs, measure extremely small magnetic fields and are valuable in the field of nanotechnology. The National Physical Laboratory (NPL) applied its expertise in quantum metrology to advance SQUID technology in a project funded by the Fifth Framework Programme of the European Commission. The NPL employed advanced imaging techniques to inspect SQUID building blocks produced by its Spanish partner Consejo Superior de Investigaciones Cientificas (CSIC). The techniques included: Atomic Force Microscopy (AFM), Magnetic Force Microscopy (MFM), Scanning Tunneling Microscopy (STM) and Low Temperature Ultra High Vacuum STM and allowed study of devices as small as 200 nanometers. During the project the NPL combined a SQUID with a magnetic tipped STM system in order to provide information about topography and magnetic spin at the same time. This discovery will facilitate future development of magnetic storage devices on the nanometre scale as well as other quantum computational research. In addition, progress on Surface Acoustical Wave (SAW) transducers was achieved. The NPL was also able to apply its know-how to assist scientists from the University of Portsmouth in nanobiology experiments. The result of the collaboration is the definition of new directions for follow-up research, aiming to overcome the difficulties encountered. The NPL is poised to take up these challenges, exploiting its accumulated knowledge in this field.