TABLE OF CONTENTS The study of both the magnetization distribution of recorded and non-recorded media is needed if magnetic recording densities are to be increased. There are various magnetic recording media depending on the type of recording drive such as hard disc drive, tape drive, magneto-optical disc drive, etc. The magnetization of the recorded bits of each medium has its own direction, i.e., parallel, oblique, or perpendicular to the medium plane. Thus, spin-SEM is advantageous to the study of these recording media, since it can detect the three components of the magnetization vector with a spatial resolution of several nanometers. In this chapter, I review how the spin-SEM contributes to increasing the recording density of various recording media.
Drawing pictures and writing characters on media such as rocks and paper was long the main method for storing information. At the end of the 19th century, Edison invented the first method for storing voices and other sounds. In this method, sounds were recorded in a spiral groove on a metal cylindrical medium and retrieved using a metal stylus combined with a membrane, which collected or emitted sound waves. These mechanical media, however, were not rewritable.
At the beginning of the 20th century, Poulsen invented a rewritable medium. He used a magnetic wire and an electromagnet to record sounds magnetically. This approach has evolved into various methods to meet the needs of various applications. During this evolution, various methods have come and gone. Today, in what we call the "information age,"...
