Disorder-driven hysteresis-loop criticality in Co/CoO-films.

Berger, A. ; Inomata, A. ; Jiang, J. S. ; Pearson, J. E. ; Bader, S. D.

Technical Information Center Oak Ridge Tennessee

关键词: Critical temperature;    Magnetization;    Cobalt;    Cobalt oxides;    Magnetic materials;   

RP-ID  :  DE2001768582

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

The effect of magnetic disorder on the magnetization reversal process in thin Co/CoO-films has been investigated. The antiferromagnetic CoO layer allows a reversible tuning of the magnetic disorder by simple temperature variation. For temperatures above a critical temperature T(sub c), we observe a discontinuous magnetization reversal, whereas smooth magnetization loops occur for T greater than T(sub c). Our measurements establish the existence of a disorder-driven critical point in the non-equilibrium phase diagram. In addition, we observe scaling behavior in the vicinity of the critical point and determine the critical exponents to (beta) = 0.022 (+-) 0.006 and (beta)(delta) = 0.30 (+-) 0.03.