Intrinsic Interactions Between Superconductivity and Magnetism in Ruthenocuprates and Quaternary and Pseudoquaternary Borocarbides

Texas A&M Research Foundation, College Station TX

Investigators

Abstract

This award supports a project to investigate the interplay between two "hostile" states, superconductivity and magnetism. The project will be carried out in collaboration with leading scientists in the Ukraine. The rare-earth-nickel-borocarbide family of compounds which exhibit a wealth of related phenomena and a system of ruthenocuprates which appear to show coexistence of magnetism and superconductivity at temperatures as high as 50K have been chosen for the study. Important length scales can be changed by introduction of point defects. This will be done by both chemical substitution and irradiation with high energy electrons in order to separate the effects related to physical disorder from those related to chemical "pressure". The research will address the role of pair breaking mechanisms in the region of coexistence of superconductivity and magnetism, the nature of exotic electronic states in this region and the anomalies in normal state transport in these magnetic superconductors. The results are expected to be of general applicability to the understanding of the interplay between superconductivity and magnetism, valid well beyond the particular material chosen. Students will receive training that will prepare them for careers in industry, academia or government. The close contact and interaction with leading scientists from another country will provide new perspectives on science and culture for these students. In addition a student from Texas Agriculture and Mining University will have the opportunity to perform research overseas in the Ukraine. This research project, a joint effort by the principle investigator and leading scientists in Ukraine, will investigate the intricate interplay between "hostile" physical states, namely magnetism and superconductivity. Two families of compounds, rare-earth-nickel-borocarbides and ruthenocuprates, which show an unusual variety of phenomena related to these two states have been chosen for the studies. The effects of disorder, introduced both by chemical substitution and irradiation with high energy electrons, on the interplay will be studied. The interplay between superconductivity and magnetism is a fundamental problem in solid state physics, and the results of this investigation are expected to lead to a much better understanding of this interplay that will be applicable beyond the chosen materials. Students will have the opportunity to collaborate with leading international scientists while learning state-of-the art technology and experimental skills. In addition a student from Texas Agriculture and Mining University will have the opportunity to perform research overseas in the Ukraine.