Room temperature exchange bias and spin valves based on BiFeO 3/SrRuO3SrTi/O3/Si (001) heterostructures

We report the growth and characterization of exchange bias and spin valve heterostructures based on the multiferroic antiferromagnet BiFe O3 on Si (001) substrates. Using Co0.9 Fe0.1 as the ferromagnet, we demonstrate heterostructures with large negative exchange bias and negligible training (or a decrease in exchange bias field as a function of repeated magnetic cycling) at room temperature. We additionally report the manufacture of spin valve structures that have been found to have current in-plane magnetoresistance of over 2.25% at room temperature. © 2007 American Institute of Physics.