Toyohashi University of Technology
Photopolymer that is a type of write-once material is the famous material used as a hologram medium. write-once type medium. A type of rewritable medium will be desired because of the enlargement of information. Presently, LiNbO3 is widely known as a good photorefractive material for rewritable media; however, we focus on magnetic media that have an ability of strage, essentially.
The process to fabricate the magnetichologram is similar to one of thermomagnetic writing. When the pulse laser goes to the saturated magnetic medium, interference pattern (hologram) is made in the medium corresponding to temperature distribution (Fig.1 (a)). The point where temperature is over the Curie temp. is demagnetized (Fig. 1(b); in the process of decreasing of temp., magnetization direction is reversed and the domain corresponding to hologram is wrote.
Fig.2 Magnetic hologram image
Fig.3 Magnetic hologram image