Formation of Non-erasable Bits on Garnet Film for Magneto-optical Recording : Perfect protection of recorded information with write-once mechanism

Abstract

When the writing laser power is higher than 10mW, non-erasable bits are formed in Bisubstituted garnet film. Write-once recording is possible also in the amorphous film which is a precursor of garnet film with laser power lower than this value. In the latter case, minimum bit length is 0.6μm and maximum CN ratio is 46dB when line velocity is 2.5m/s and bit length is 3μm. These results lead to the following attractive and useful applications. That is, the perfect protection of information in a magneto-optical recording medium from magneto-electrical or thermal disturbance, the novel recording material which can be utilized both for write-once recording and magneto-optical recording, and the high sensitive write-once recording material.