Search for Higher Temperature Superconductors by Novel Approaches.

Abstract

Abstract : Under the partial support of USAFOSR Grant No. F 49620-93-1-0310 by BMDO from June 1993 through October '95 the Principle Investigator, C. W. Chu, showed that superconductivity occurs at record high temperatures in mercury based compounds up to 134 K and 164 K at ambient and high pressures, respectively, making it possible to operate superconducting devices in a space environment without the help of liquid coolant and on earth simply with the aid of household air conditioner technology, and in a compound of Ba-Ca-Cu-O without toxic elements up to 124 K at ambient pressure. A demonstration experiment is under way in collaboration with the National Aeronautics and Space Administration (NASA). He was the first to make thin films of this class of compounds, demonstrating the possible attainment of superconducting electronics with superior performance. He demonstrated the feasibility of constructing an ultrafast high powered high temperature superconducting switch with profound implications for the defense and civilian technologies. Many of the new and improved compounds resulting from the present study also enabled him to examine some crucial issues of high temperature superconductivity and to show that recent claims of superconductivity near room temperature are premature.