Abstract

This Handbook is in large part a materials science handbook for superconductors. A central tenet of materials science holds that the properties of material are related to the material structure and the fundamental bonding of atoms, whereby property changes can be attained by manipulating the material structure. In this discussion, the context for structural studies spans a wide range of length scales. At the smallest scales, the atomic precision of a material and its defect structure over few nanometers relates to properties connected with the superconducting coherence length, especially in superconductors with high critical temperature and coherence length approaching 1 nm. Somewhat larger structures affect properties related to critical current and flux pinning, including precipitates, strain fields, material grains, boundaries and interfaces, and dispersion of chemical dopants. Synthesis of superconducting phases furthermore depends on microscale diffusional growth at scales of micrometers and higher. Finally, macroscale features of conductors and conductor assemblies in cables, questions related to conductor uniformity, predictability, and reliability span lateral dimensions of millimeters and higher, in lengths of kilometers.