ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Giant magnetoresistance (GMR) is reported in Ag1−xCox(x=0.26–0.53) films cosputtered on Si at 28–354 °C from separate Ag and Co targets. GMR ratios (10 kOe maximum field) as high as 0.55 and 0.24 at 5 and 295 K, respectively, are achieved for the Ag0.67Co0.33 films deposited at a substrate temperature, Ts, of 125 °C. The GMR ratio increases slightly when the Ts increases from 28 to (approximately-equal-to)125 °C, and decreases substantially at Ts(approximately-greater-than)175 °C. The resistivity of these films decreases monotonically with increasing Ts and levels off to a value (approximately-equal-to)3× of Ag at Ts≥250 °C. The films deposited at lower Ts consist of essentially a metastable Ag-Co solid solution, while those deposited at higher Ts consist of separate fcc Ag and fcc Co. The coercivity of these films increases rapidly at Ts(very-much-greater-than)125 °C, consistent with the growth of single-domain ferromagnetic Co particles in this Ts range. The Ts dependence of GMR ratios is interpreted based on spin-dependent interfacial scattering arising from the Ts dependence of the size and number of ferromagnetic Co particles within the electron mean free path.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.354159
