Influence of Temperature on Magnetic Properties of Tb26Co74/Co/Fe20Ni80Films with Exchange Bias

Abstract

Magnetic multilayers with unidirectional magnetic anisotropy, which reveals itself as a shift of the hysteresis loop of the soft magnetic layer along the magnetic eld axis, have been studied intensively for the last two decades [1 6]. Thin lms consisting of exchange coupled Fe20Ni80 and Tb Co layers are of substantial fundamental and applied interest [1 6]. Due to the proper combination of magnetic and magnetoresistive properties such lms have been used in magnetic sensors [5]. Previously hysteresis properties of these layered structures were shown to be determined mostly by the character and e ectiveness of the interlayer coupling, which in turn is de ned by structural and chemical condition of interfaces. Interlayer region can be modi ed arti cially by introduction of the ultrathin nonmagnetic spacer [4] or by selective annealing of the seed permalloy layer [5]. This paper is devoted to the study of in uence of temperature on unidirectional anisotropy in exchange coupled sandwiches based on Tb26Co74 ferrimagnetic layer and Fe20Ni80 soft magnetic layer separated by the ultrathin Co spacer.