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Cover Picture (Angew. Chem. Int. Ed. Engl. 11/1989)
Publication year - 1989
Publication title -
angewandte chemie international edition in english
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 0570-0833
DOI - 10.1002/anie.198914451
Subject(s) - cover (algebra) , magnetization , magnetism , condensed matter physics , physics , materials science , nanotechnology , quantum mechanics , engineering , mechanical engineering , magnetic field
The cover picture shows a pattern of data (0,1,0,1,0…)—pits—on a magneto‐optic storage disk which is read with a semiconductor laser. The storage medium is a lanthanoid‐transition metal alloy, whose magnetism is directed upwards and perpendicular to the disk. In the bright domains (ca. 1 μm) the magnetization is directed perpendicularly downwards. The plane of polarized light is rotated by the data pits, so that the magnetization pattern can be observed with a microscope. The data are read with the laser beam according to a similar principle. For determining the dynamic write‐read properties, pits have been marked with three different frequencies. Guide grooves in the surface serve for orientation on the disk. More about materials for optical data storage is reported by M. Emmelius et al. on page 1475 ff.