Overview
This project was a collaboration between the labs of Dr. Julia Y. Chan and Dr. John F. DiTusa, in which we synthesized a compound which potentially possessed colossal magnetoresistant qualities, to be used in home security systems.
Magnetism Abstract
Room temperature colossal magnetoresistance (CMR) has recently been discovered in the double perovskite Sr2FeMoO6 [1], where there is evidence for valence fluctuation of Fe to give a formal charge of Fe(2.5+)[2]. Compounds that display CMR behavior are of use for applications such as magnetic storage devices and magnetic sensors commonly used in home security systems. We want to study other Fe-containing oxides to determine if a chemically induced valence fluctuation of Fe will yield physical properties that are similar to those found for Sr2FeMoO6. Therefore, compounds of LiFeSi2O6, NaFeSi2O6, NaFeSi2-xAlxO6, and Ca2Al(Al0.5SiO.49Cr0.01)O7 have been prepared by ceramic methods. Powder X-ray diffraction was used to monitor the formation of each phase through successive heat treatments.
References
[1] K.-I. Kobayashi, T. Kimura, H. Sawada, K. Terakura, and Y. Tokura. Nature 1998, 395, 677.
[2] J. Linden, T. Yamamoto, M. Karppinen, H. Yamauchi, and T. Pietari. Appl. Phys. Lett. 2000, 76, 2925.
[2] J. Linden, T. Yamamoto, M. Karppinen, H. Yamauchi, and T. Pietari. Appl. Phys. Lett. 2000, 76, 2925.