Common methods of local magnetic imaging display either a high spatial resolution and relatively poor field sensitivity (MFM, Lorentz microscopy), or a relatively high field sensitivity but limited spatial resolution (scanning SQUID microscopy). Since the magnetic field of a nanoparticle or nanostructure decays rapidly with distance from the structure, the achievable spatial resolution is ultimately limited by the probe-sample separation. This thesis presents a novel method for fabricating the smallest superconducting quantum interference device (SQUID) that resides on the apex of a very sharp tip. The nanoSQUID-on-tip displays a characteristic size down to 100 nm and a field sensitivity of 10^-3 Gauss/Hz^(1/2). A scanning SQUID microsope was constructed by gluing the nanoSQUID-on-tip to a quartz tuning-fork. This enabled the nanoSQUID to be scanned within nanometers of the sample surface, providing simultaneous images of sample topography and the magnetic field distribution. This microscope represents a significant improvement over the existing scanning SQUID techniques and is expected to be able to image the spin of a single electron.

Common methods of local magnetic imaging display either a high spatial resolution and relatively poor field sensitivity (MFM, Lorentz microscopy), or a relatively high field sensitivity but limited spatial resolution (scanning SQUID microscopy). Since the magnetic field of a nanoparticle or nanostructure decays rapidly with distance from the structure, the achievable spatial resolution is ultimately limited by the probe-sample separation. This thesis presents a novel method for fabricating the smallest superconducting quantum interference device (SQUID) that resides on the apex of a very sharp tip. The nanoSQUID-on-tip displays a characteristic size down to 100 nm and a field sensitivity of 10^-3 Gauss/Hz^(1/2). A scanning SQUID microsope was constructed by gluing the nanoSQUID-on-tip to a quartz tuning-fork. This enabled the nanoSQUID to be scanned within nanometers of the sample surface, providing simultaneous images of sample topography and the magnetic field distribution. This microscope represents a significant improvement over the existing scanning SQUID techniques and is expected to be able to image the spin of a single electron.

Understanding the nature of vortices in high-Tc superconductors is a crucial subject for research on superconductive electronics, especially for superconducting interference devices (SQUIDs), it is also a fundamental problem in condensed-matter physics. Recent technological progress in methods for both direct and indirect observation of vortices, e.g. scanning SQUID, terahertz imaging, and microwave excitation, has led to new insights into vortex physics, the dynamic behavior of vortices in junctions and related questions of noise. This book presents the current status of research activity and provides new information on the applications of SQUIDs, including magnetocardiography, immunoassays, and laser-SQUID microscopes, all of which are close to being commercially available.

On the current status of research activity, providing new information on the applications of SQUIDs, including magnetocardiography, immunoassays, and laser-SQUID microscopes, all of which are close to being commercially available.

This handbook is about a remarkable set of materials that are technically referred to as "mesoscopic superconductors", which for all practical purposes are tiny or small in their dimensions, ranging from a few micrometers down to a nanometer. At this level of smallness, the superconducting properties are dramatically changed, showing the dominance of quantum effects. Ground breaking research studies of small superconductors have emerged, and in a world obsessed with miniaturization of electronic device technology, small superconductors acquire even greater relevance and timeliness for the development of exciting novel quantum devices. The chapters, contributed by noted researchers and frontrunners in the field from 15 countries, are presented in three parts, namely progress in basic studies, materials specific research, and advances in nanodevices. The contents of the handbook should be of immediate interest to advanced level university students and researchers particularly in physics, materials science, nanoscience and engineering departments. Various reviews and overviews appearing in the book should answer the queries and curiosities of non-specialists interested in nanoscale superconductivity. At the start, the book carries an extended introduction for readers new to the field. The book should also appeal to scientists and engineers from electronic industries interested in knowing the current status of the theory, manufacture, and future of mesoscopic superconductors. In doing so, this volume offers the opportunity to engage with cutting edge research in one of the most exciting fields of physics today and tomorrow.