Interactions in Nanoscale Arrays of Soft Magnetic Bi-Layers
Magnetic bi-layers are becoming increasingly popular as a medium for perpendicular patterned media. In order to understand the net interactions between the layers and between adjacent magnetic elements in an array, we use a coupled Preisach model to model the hysteresis loops we measured for a sample consisting two magnetically soft layers of FeCoTaZr, separated by an 0.8-nm Ru spacer layer. The model reproduces the major hysteresis loop to decent agreement. The model was then decoupled to reveal the reversal behavior of the individual layers. This paper demonstrates that coupled Preisach modeling of the hysteresis loop is an effective tool to analyze such interacting material systems.
Micromagnetic Structure of Co Stripe Arrays With Tuned Anisotropy
We report on the study of magnetic properties and the domain structure of single Co microstripes and their arrays, lithographically patterned on the Si substrate. Microstripes have the shape anisotropy and the anisotropy induced by the oblique deposition. We considered two cases, when these anisotropies are either codirectional or perpendicular to each other. As was found, the coercive force depends on the width and the number of stripes in an array. The mutual orientation of both anisotropies defines the type of the magnetic domain structure.
On design of Co-Cr perpendicular recording media for usage of a ring-type head
Co-Cr double-layer media were studied in order to improve perpendicular magnetic recording by using a ring-type head. A very thin semihard back layer (only 100 AA) with a high saturation moment showed a dramatic increase of reproducing output over a wide density region, while the recording sensitivity was also improved. The reproduced waveform with a sharp single peak desirable for actual systems occurs with peak shift as small as that for a single-layer Co-Cr medium. It is supposed that these improvements are caused by reduced demagnetization in the recording process. Design concepts of the media are discussed. >