Influence of Crystal Lattice Defects on Domain Wall Nucleation and Motion in Exchange-Bias Films

V.I. Nikitenko$^{* \dag }$, V.S. Gornakov^*, L.M Dedukh^*, A.J. Shapiro^**,
R.D. Shull^**, A. Chaiken^***

^*Institute of Solid State Physics, Russian Academy of Sciences,
142432, Chernogolovka Moscow District, Russia
^**National Institute of Standards and Technology, Gaithersburg, MD 20899
^***Hewlett-Packard Laboratory, Palo Alto, CA 94304

Presented as paper L3.3 at the Spring '98 Materials Research Society Meeting.

The effect of dislocations on the elementary events of the magnetization reversal processes in exchange-biased NiFe/NiO bilayer films and in free NiFe films grown on MgO substrates were investigated using the magneto-optic indicator film technique and vibrating sample magnetometry. It was revealed that dislocations not only influence the spatial distribution of spins, resulting in their inhomogeneous rotations during remagnetization, but also stipulate the formation of unusual quasi-one-dimensional domains localized on dislocation slip planes. Asymmetry in the dislocation activity as domain wall nucleation centers was investigated, and possible reasons for the revealed phenomena are discussed.

• Introduction
• Experimental Methods
• Results and Discussion
• References
• Figures