Abstract
The effective magnetoelastic (ME) coupling coefficients Beff of polycrystalline Ni79Fe21 and Ni films have been reported as functions of thickness t. Beff was observed to have a thickness-independent bulk term, Bb, and a thickness-dependent surface term, Bs/t consistent with the Neel model. For thickness below 50 Å the surface term is important; it can change the sign of the effective ME coupling constant and dramatically increase its magnitude. We expect that the surface ME coupling we observe in polycrystalline thin films may be a combination of the intrinsic Néel surface effect and extrinsic microstructure effects. Our transmission electron microscopy, Auger depth profiling, and atomic force microscopy rule out film discontinuity and compositional gradients as significant sources of the surface ME effect.
Original language | English |
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Pages (from-to) | 3141-3144 |
Number of pages | 4 |
Journal | Journal of Applied Physics |
Volume | 79 |
Issue number | 6 |
DOIs | |
State | Published - 15 Mar 1996 |