A major objective of the grant is to investigate ballistic magnetoresistance (BMR) in magnetic nanocontacts in technologically important magnetic nanostructures based on the magnetic transition metals (Ni and Co) as well as the half-metallic magnetite system. The nanocontacts will be made using electrodeposition techniques along with nanometer size sharp tips fabricated using electrochemical methods. A principal objective is to make a systematic study of the effects of contact diameter, local domain structure and the composition of the nanocontacts on BMR. The results from the study will constitute fundamental understanding of spin-polarized electron transport across nanometer-sized magnetic constrictions. The contact diameters will be selected spanning from diffusive to ballistic electron transport regimes. The development of BMR nanocontacts would greatly enable the current data storage capacity to be increased from the current Gbits per square inch range to the terabits per square inch range. The collaborative research between SUNY Buffalo and Arizona State University involves participation at NIST for imaging magnetic structures using Scanning Electron Microscopy with Polarization Analysis (SEMPA).
The research on microfabricated nanocontacts supported on a solid substrate find a range of useful applications as stand-alone units such as in ultra-high sensitivity magnetic sensors as well as novel biological sensors where a given molecule can be made to give its own unique electronic signature. Along with the laboratory training of researchers at graduate and undergraduate levels, outreach activities include a five-week summer apprentice program for minorities and women students from Buffalo-area inner city high schools.
