Towards Hall effect spintronics

Major efforts in the current exploration of spintronics are focused on the giant magnetoresistance (GMR) phenomenon in metallic, semiconducting and tunnel junction magnetic heterostructures. I wish to present a different approach based on the extraordinary Hall effect (EHE). Since its discovery more than a century ago, the EHE was not considered seriously for technological applications because of its relatively small value in bulk magnetic materials. Several techniques were recently developed to significantly enhance the effect. Field sensitivity of tens to hundreds Ω/T has been obtained. We argue that EHE-based sensors and memory devices promise a number of valuable advantages, including high sensitivity, thermal stability and simplicity and low cost manufacture, and can become an alternative to the GMR.