Objectives:

This module will serve as a necessary introduction to the course as well as the manifestation of the magnetic anisotropy property of solid state materials focused to magnetic recording devices, viz., magnetism. We will start our quest with a look at the historical development of magnetic recording techniques. This would not only provide an account of the evolution of the magnetic recording techniques, but would also point towards the future of recording process. This would be followed by understanding the directional dependence of magnetic properties of magnetic materials or magnetic anisotropy and the factors that influence this. We will close this chapter by taking a look at the soft and hard magnetic materials and their characteristics.

 

Therefore, the following five lectures would cover the following topics:

1. How magnetic recording has evolved over the years?

2. What are the different forms of magnetic media?

3. What is magnetic anisotropy energy and what are the factors that contribute to it?

4. What is magnetostriction?

5. What are soft and hard magnetic materials?

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Figure 1.1: Schematic drawing of analogue magnetic recording.