MAGNETORESISTANCE AND MAGNETIC PROPERTIES OF ELECTRON BEAM DEPOSITED (Co_(50)Fe_(50)_xAg_(1-x) GRANULAR FILMS

摘要

A series of (Co_(50)Fe_(50))_xAg_(1-x) granular thin films of composition (0.08 < x < 0.80, x is volume fraction) and 400 nm thickness were deposited on glass substrates at room temperature by dual electron-beam evaporation technique. The structure of the films was investigated by X-ray diffraction. The measurements of electrical resistance, giant magnetoresistance (GMR) and magnetic investigations were carried out in the temperature range from 5 K to 300 K and at magnetic fields (H) up to 50 kOe. The films of composition x < 0.26 show isotropic GMR. Maximum values of magnetoresistance - 35% (T= 10 K; x - 0.13) and - 17% (T= 300 K; x = 0.19) were observed at 50 kOe. The temperature dependences of electrical resistance and GMR vs. x at different temperatures and magnetic fields were analysed. As shown, small superparamagnetic particles and paramagnetic impurities significantly affect transport properties of granular films.