Giant magnetoresistance in manganese oxides

Giant magnetoresistance (GMR) was known to occur in metallic bilayers and granular materials. In 1993, GMR was also found to occur in thin films of manganates of the formula La1−xAxMnO3 (A=alkaline earth metal). Since then, there has been intense research activity relating to the GMR of rare earth manganates and other oxides.