GB1367126A - Magnetic bubble domain system - Google Patents

Abstract

1367126 Moving domain devices ROCKWELL INTERNATIONAL CORP 26 Jan 1972 [12 March 1971] 3732/72 Heading H3B Magnetic bubble domains are propagated in a strip of material 12, Fig. 1, on a substrate 10, and predetermined stable positions are introduced by removing portions of the strip such as 14, 15. The domains are repelled by the strip edges, and thus where the strip width is reduced a greater force is required to propagate the domains. The domains therefore collect singly or in groups in the regions of full width such as 20. Any geometric restriction of the film may be used, such as a reduction in its height, the notches in the Fig. 1 film need not pass all the way through the height of the film. The strip may be embedded in the substrate or other material may be placed beside the strip as in Figs. 3, 4 (not shown). Specification 1,352,791. The substrate is preferably a garnet of formula J 3 Q 5 O 12 , where J is one or more of Y, Ca, Bi and the rare earths, Q is one or more of In, Ga, Sc, Ti, V, Cr, Mn, Rh, Zr, Hf, Nb, Ta, Al, P, As, Sb. Examples are Sm 3 Ga 5 O 12 , Y 0À45 Gd 2À55 Ga 5 O 12 and Dy 0À65 Gd 2À35 Ga 5 O 12 . The bubble domain material is also preferably a garnet of J 3 Q 5 O 12 formula, where J is one or more of Y and the rare earths, Q is Fe, Fe and Al, Fe and Ga, Fe and In, Fe and Sc, Fe and Ti, Fe and V, Fe and Cr, Fe and Mn. Examples are Y 3 Ga 1À2 Fe 3À8 O 12 and Tb 3 Fe 5 O 12 .