Influence of the magnetic field on the structural characteristics of granular CoxAg100-x thin film alloys

• Published in: Thin solid films Vol. 724
• Main Authors: Shpetnyi, I.O., Pak, V.Ya, Shkurdoda, Yu.O., Vorobiov, S.I., Derecha, D.O., Hruzevych, A.V., Sharai, I.V., Kravets, A.F., Gorobets, Yu.I., Satrapinskyy, L., Luciński, T.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.04.2021
• Subjects: co-evaporated technique; giant magnetoresistance; granular thin films; magnetic aftereffect; magnetoresistive properties; magnetoresistive properties; magnetic aftereffect; granular thin films; co-evaporated technique; giant magnetoresistance
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2021.138613

•The maximum value of giant magnetoresistance is observed at xCo=39 at%.•The application of a magnetic field leads to a decrease in surface roughness.•Relaxation (18 h) does not affect the structural characteristics of the surface. We investigated structural-phase state, magnetic and magnetoresistive properties in as-deposited CoxAg100-x thin film alloys with a thickness of 35 nm as a function of composition (20 ≤ x ≤ 80 at.%). The aim of this work was to obtain a granular thin film alloy CoxAg100-x with the maximum amplitude of the giant magnetoresistance (GMR) and study of the magnetic field effect on structural characteristics of its surface. Studies of the effect of the magnetic field on the structural characteristics of the surface of the granular thin film alloy Co39Ag61, that characterized by the highest amplitude of GMR at room temperature, were performed. The GMR value for this sample was 14.7 % in transverse and 13.6 % in longitudinal measurement geometries under the magnetic field Bmax = 1.5 T. The application of the magnetic field led to a decrease in arithmetic mean Ra and the root mean square Rq values of the surface roughness, as well as the structural entropy of the system. At the first application of the magnetic field, the greatest decrease in the roughness of Ra by 19 % and Rq by 16 %, respectively, was observed. These changes persisted with increasing field strength up to B = 0.1 T. During the relaxation process (18 hours after the field was switched off), the structural characteristics of the sample were permanent.