One of the most exciting areas of research in condensed matter physics in recent years is high temperature superconductivity.
Superconductivity is a very subtle phenomena.
Perhaps the most intriguing is the fact that it shows quantum mechanical behavior on a human scale. These quantum interference properties can be used to make very sensitive detectors of electromagnetic fields. This is just one of many technological applications of superconductivity. Recent discovery of superconductivity in Copper Oxide based ceramic materials, above 100 degrees K, may allow us to overcome some of these limitations. Understanding the phenomenon of superconductivity has occupied some of the best minds of our times.