Peculiarities of Magnetoresistance of [Fe/SiO]n Discontinuous Multilayers

Abstract

The influence of the magnetic and insulator layer thickness on the crystal structure and magnetoresistive properties of [Fe/SiO]n discontinuous multilayers has been studied. The results indicate that the decreasing of Fe layer thickness within the range from 10 to 3 nm leads to the transition of microstructure of the samples from nanocrystalline to amorphous. For all investigated systems in an as-deposited state, the isotropic nature of the field dependences of magnetoresistance is observed. For samples with layer thickness dFe = 4–6 nm and dSiO = 5 nm, the transition to isotropic MR occurs after annealing to 400 K. However, for samples with Fe layer thickness of 7–10 nm, such transition is not observed regardless of the effective thickness of insulator layer and annealing temperature.