Neutron study on the subject of giant magnetoresistance effect

Giant magnetoresistance is often discussed with the interfacial roughness in magnetization and/or the structural disorder. Polarized neutrons are particularly powerful for probing such a disordered state through the magnetic and lattice structure analysis. We renew in this paper our polarized-neutron experiments carried out on the TOP spectrometer installed at the pulsed neutron facility, KENS, investigating the magnetic structure relating to giant magnetoresistance. We confirmed that giant magnetoresistance occurs when the magnetic moment is aligned antiparallel, with every other layer separated by a nonmagnetic spacer layer. The diffusive off-specular reflection of magnetic origin suggested that the magnetic disorder near the interface might be related to the appearance of the magnetoresistance effect.