Thin film magnetism strengths

The anisotropy behavior near the compensation point has received considerable attention for the R-T alloys and R/T multilayers. It is usually considered that the heavy R and T are coupled ferrimagnetically like a rigid body, i.e. the coupling strength A is infinity. Based on this assumption, the magnetic energy of a thin-film sample is written as (Heilman 1991) ... 

Critical current densities on the order of 10 A cm at 77 K in zero field were measured on BSCCO thin films. In Fig. 4.2-46 the field dependence of 7c of a B12212 film is shown for two temperatures [2.90] and Fig.4.2-47 demonstrates the Jc(B, T) dependence of a B12223 film [2.87]. In magnetic fields aligned parallel to the plane of the film, that is perpendicular to the c axis of the crystal structure, 7c is practically independent on the field strength, even at higher temperatures such as 60 K. The reasons for this behavior are discussed below in connection with the Jc(B, T) correlation of wires and tapes. 

This technique has only recently evolved into an important method for magnetometry. This technique has unique strengths in that it can be used to determine quantitatively spin and orbital magnetic moments for specific elements, and can also be used to determine their anisotropies through analysis of the experimental spectra. For example, XMCD has been applied to the study of thin films of transient metal multilayers, such as Cu or Fe. 

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