Analysis of mixed ternary LREBa2Cu3Oy nano-structures by STM and TEM

This review reports on two new nanometer scale pinning media in melt-textured LREBa2Cu3Oy superconductors and the ways of their creation. Microstructure analysis by transmission electron microscopy (TEM) and scanning tunneling microscopy (STM), capable of recognizing nanometer size pinning defects, show their shapes and dispersion and identify the key structural features responsible for the improved superconducting performance. The two new pinning agents extend the use of LREBa2Cu3Oy composites towards high magnetic fields and high temperatures.