Perpendicular magnetic anisotropy

Development of Permanent Magnet Thin Films with Very High Perpendicular Magnetic Anisotropy... 

Figure 7.9a shows M-H hysteresis loops for a typical sample with the Cu underlayer (sample A). The substrate temperature was set at an elevated temperature of 345°C for the deposition of aU layers. The values of and squareness ratio (SQR) measured in the perpendicular direction are hsted in Table 7.1 together with the values of and of the SmCOj((X)2) reflection in an X-ray diffractometry, defined as the values of full width at half maximum obtained from the rocking curves. Both and SQR in the perpendicular direction were greater than those in the film plane, indicating that perpendicular magnetic anisotropy was clearly generated. The value... 

Fig. 7.9 M-H hysteresis loops of SmCOj thin films with perpendicular magnetic anisotropy, (a) Sample A, (b) sample B, and (c) sample C correspond to those in Table 7.1. Thick and thin lines represent the loops measured in the directions perpendicular and parallel to the film plane, respectively [45]...

Iwasaki S, Ouchi K (1978) Co-Cr recording films with perpendicular magnetic anisotropy. IEEE Trans Magn 14 849-851... 

Carcia PF, Meinhaldt AD, Suna A (1985) Perpendicular magnetic anisotropy in Pd/Co thin film layered structures. Appl Phys Lett 47 178-180... 

Sayama J et al (2004) Newly developed SmCo thin film with perpendicular magnetic anisotropy. J Phys D Appl Phys 37 L1-L4... 

Sayama 1 et al (2006) Origin of perpendicular magnetic anisotropy of SmCo thin films with Cu underlayer. 1 Magn Magn Mater 301 271-278... 

Takei S, Moiisako A, Matsumoto M (2004) Fabrication of Sm-Co films with perpendicular magnetic anisotropy. 1 Magn Magn Mater 272-276 1703-1705... 

The media were assumed to consist of a monolayer of hexagonal dots with saturation magnetization of 300 emu/cc, a perpendicular magnetic anisotropy field... 

Shimatsu T et al (2004) High perpendicular magnetic anisotropy of CoPtCr/Ru films for granular-type perpendicular media. IEEE Trans Magn 40 2483-2485... 

Itoh et al. (1983) report that the perpendicular magnetic anisotropy in Gd-Fe films, when prepared by means of sputtering under low substrate bias voltage, is mainly stress determined. In alloys where the R component is a non-S state ion the... 

Esho (1979) found that strong perpendicular magnetic anisotropy can be obtained in thin amorphous Gd-Co films by sputtering in the absence of bias voltage in the presence of Nj gas contaminations. Esho considers the presence of two sources for the anisotropy, a bias-induced positive anisotropy and a microcrystalline negative anisotropy. The relative contributions of both types are assumed to depend on details of the microstructure, i.e. on details of the method of preparation. 

The dependence of magnetic properties on fiber alignment was reported by Sharma et al. [185]. They prepared coaxial fibers of PEO incorporating Fe203 NPs that exhibited perpendicular magnetic anisotropy when collected as parallel fibers. 

The goal of this chapter is to review recent advances in our understanding of the magnetic structure, the interfacial magnetism, and the origin of perpendicular magnetic anisotropy (PMA) of lanthanide-transition metal nanoscale multilayers, here denoted as R/T. We do not intend to review all of the recent work on these subjects, but rather will focus on discussing either newly understood phenomena by means of a few illustrative experiments, or those aspects which are not yet understood and therefore require additional work. 

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