Office: RH 306B
My research on magnetic materials has focused on the preparation and characterization of new magnetic alloys. Samples are first prepared by arc melting the elements in the proper atomic ratios in an argon atmosphere. Then they are cut into pieces with a diamond saw. X-ray measurements are made to determine the quality of the alloy, and if the sample is of acceptable quality then magnetic and resistivity measurements are made. The aim of all studies is to determine the factors that control the magnetic state of the material, then to be able to design materials with the desired magnetic characteristics. Some of the systems I have studied so far are the Kondo lattice system CeSix, the rare earth pyrochlore compounds R2Mo2O7 (R = rare earth), the reentrant magnetic materials CeMn2(GexSi1-x)2, and most recently the R5Si3 series. Currently I am working on the hard magnetic materials R2Fe17-xMx (M = metal) and their carbides. It is hoped that we can identify some materials suitable for development into the much-needed high temperature permanent magnets.
Research is carried on in collaboration with researchers at Southern Illinois University at Carbondale, where we have access to arc melting and powder sample preparation facilities as well as a wide array of sample characterization equipment, including a Lakeshore Model 7000 ac susceptometer, Quantum Design SQUID magnetometer with a 5.5 Tesla magnet, and a capacitance dilatometer, for relative thermal expansion measurements. X-ray diffraction measurements are carried out here at Southeast in collaboration with Dr. Michael Aide in Geosciences. I am currently developing a sensitive resistivity measurement system which will yield the resistivity of magnetic alloys from temperatures of 4 K to 300 K and later also as a function of applied field. This system with be computer interfaced for automated data acquisition and control.