Professors Jody G. Redepenning and Bernard Doudin of the University of Nebraska-Lincoln are supported by the Analytical and Surface Chemistry Program in the Division of Chemistry to develop chemically modified nano-electrodes to be used in magnetoelectronic devices, such as permanent memories, reconfigurable logics, and fast electronic components. To accomplish this goal, the investigators plan to explore two types of barriers and to reduce the size of the junctions. One will be comprised of silicon oxide produced by repetitive hydrolysis/condensation of tetramethylorthosilicate on the surfaces of the electrodes. A second class of junctions will be produced by irreversible polymerization of appropriate metal complexes onto the surfaces in the junction. The idea is to passivate the surfaces of magnetoresistance tunnel junctions while introducing thin dielectric materials with controllable properties. The goal is to understand the elusive properties of barriers and how resonant tunneling effects occur. The discovery of giant magneto-resistance led to commercial devices such as hard-disk read heads, magnetic field sensors and magnetic memory chips. Tunnel magneto-resistance devices are another example of development from laboratory proof of principle to industrial applications within a remarkably short time. Future generations of magnetic sensors and memory elements are likely to be be constructed in the nano-scale. Understanding magnetoresistance properties at the nanoscale will help build the knowledge base required for future device miniaturization. This research will involve graduate students, undergraduate students, and high-school teachers, giving them complementary and interdisciplinary education in nanotechnology. The interdisciplinary nature of this project will create new synergies between chemists and physicists.
