Magneto-optical characterization of thin garnet media

Magneto-optical(MO) recording, over the last 10 years or so, has emerged as a viable method of recording and retrieving large amount of information. Recording densities of 10(8) bits/cm, Giga-byte capacity, non-contact recording and disk removability are some of the advantages of MO technology. However, present day MO recording technology uses rare-earth(RE) and Transition metal (TM) thin films as recording media which have undesirable properties e.g., low Kerr rotation angle and poor corrosion resistance. To overcome these shortcomings, other thin films have been under investigation and this paper presents a systematic analysis and magneto-optic characterization of some novel ferrimagnetic garnet thin films to assess their suitability as MO media. Various garnet films were fabricated using Facing Target Sputtering (FTS) magnetron technique. Experiments with a specially developed Magnetic domain observation set-up were carried out to investigate the stability and reproducibility of magnetic information bit formation under various writing/erasing parameters and environmental conditions. Results are compared with the existing commercially available MO media.