Magnetostriction transverse

Oriented In-Plane Texture. In this kind of film the properties (H and in the various in-plane directions (texture and nontexture directions) are different. The texture of the film can be supported by the texture of the substrate and the crystal lattice can be smaller in the texture direction than in the transverse direction. This can be the source for strain-induced magnetic anisotropy (magnetostriction). It is also found that the crystal is aligned in the texture direction (92). 

Kadomtseva et al. (2000) measured thermal expansion and longitudinal and transverse magnetostriction in pulsed magnetic fields up to 25 T in Lai - Sr MnOj single crystals (x = 0.1,0.125 and 0.15). The results were ascribed to a suppression of the O phase and field-induced transitions to a new orbital-ordered ferromagnetic state. 

Figure 9. Transversal (a) and longitudinal (b) magnetostriction of a Lao 8Ca0.2CoO3 single crystal along the [110] crystallographic axis at different temperatures.

Jensen (1971) and Vigren and Liu (1972). The theory is an extension of the static magnetostriction to the dynamic situation, and this kind of interaction failed to explain the splitting A between the MA mode and the transverse optic phonon (TO). A similar situation exists in Dy where the mixing of the optic magnon (MO) and TA mode was seen (Nicklow et al., 1972). 

Three estimates of the shear magnetostriction parameter have been made for Tb (fig. 6.34). By measuring the field dependence of the velocity of transverse sound waves propagating in the c-direction, Moran and Luthi 119701 deduced A" = 7.3 x 10 at 140 K (o- = 0.82). Jensen and Houmann (1975) determined a value of 8.5 x 10 at 53 K (a = 0.97) from their analysis of magnon-phonon interactions in the c-axis dispersion relation. These results are consistent with the strain gauge measurements of De Savage and Clark (1965), taken in the paramagnetic phase. 

It should be noted that the transverse component of the VV susceptibility depends on the orientation of the magnetic field in the plane perpendicular to the crystal c-axis. This dependence is due to the anisotropy of the electronic Zeeman interaction and to magnetostrictive deformation, as mentioned in sect. 3.2. In the weak fields such an angular dependence was registered only by NMR methods (Al tshuler et al. 1982). 

In a transverse magnetic field Hq J. [001] the field and temperature dependences of the induced longitudinal magnetostriction in the LiTbp4 dipolar ferromagnet in accordance with eqs. (233), (235), and (241) are described by the expression... 

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