Coercive changes

Che] Vibrating sample magnetometer Coercivity change diffusion of Cu into PtFe thin film. 

Coercive change promotes limited commitment and fosters alienation and detachment... 

Fig. 6. Changes in ( coercive force, (----) saturation magnetization Af, and (— —) coercive squareness ratio, A, of Co—Cr—Ta/Cr films...

In general, the effect of additives (supporting electrolyte) to the electroless Co(P) solution results in changes of the coercivity values of the product films. In line with this, coercivity of up to 1000 Oe in electrolessly produced Co(P) films was shown to be possible in Ref. 77. 

One possible, although speculative explanation of the effect of the addition of sulfamic acid or sodium sulfate may be based on Eq. (4.9). According to this equation, the variation in the concentration c of a nonreacting electrolyte changes the thickness of the metal-solution interphase, the double-layer thickness It appears that as the thickness of the double layer, decreases, the coercivity of the Co(P) deposited decreases as well. 

Electrolessly plated cobalt-phosphorus thin films are usually characterized by low- to medium-coercivity values (300 to 900 Oe). For some apphcations it would be desirable to have films with coercivities greater than 900 Oe. Table 16.1 shows that films with minimum preferred orientation exhibit maximum coercivity values. The ratio of the intensity of the (002) and (101) diffraction rings changes with hypophosphite concentration of the plating solution, with zero preferred orientation obtained at solution hypophosphite concentrations of 5 to 6 wt %. 

The amount of energy (i. e. the coercive forces) necessary to achieve these changes is related to three different types of magnetic anisotropy. 

Gomert, P. Buske, N. (2000) Preparation, characterization and applications of ferro-fluids. 5 Intertech Conference, Berlin Goss, C.J. (1988) Saturation magnetization, coercivity and lattice parameter changes in the system Fe304 - y- Fe203, and their relationship to structure. Phys. Chem. Min. 16 164-171... 

A second type of behavior existing in the PLZT s is the linear (Pockels) effect which is generally found in high coercive field, tetragonal materials (composition 3), This effect is so named because of the linear relationship between An and electric field. The truly linear, nonhysteretic character of this effect has been found to be intrinsic to the material and not due to domain reorientation processes which occur in the quadratic and memory materials. The linear materials possess permanent remanent polarization however, in this case the material is switched to its saturation remanence, and it remains in that state. Optical information is extracted from the ceramic by the action of an electric field which causes linear changes in the birefringence, but in no case is there polarization reversal in the material. 

Fig. 29. The changes of the in-plane magnetisation, coercivity and magnetostriction as a function of substrate temperature Ts in Tbo.27Dyo.73Fe2 films. After Wada et al. (1997c).

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