The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 06, 1976
Filed:
Nov. 12, 1973
Erik Klokholm, Stamford, CT (US);
Thomas S Plaskett, Katonah, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Bubble domain devices using conventionally known elements for providing a plurality of bubble domain functions, including writing, storage and reading, are provided using a magnetic medium of garnet structure characterized by the presence of a single rare earth ion present in all available dodecahedral lattice sites. These devices operate well over room temperature ranges. This material has sufficiently high anisotropy (of the order 10.sup.5 ergs/cm.sup.3) to support stable magnetic bubble domains in the material. The anisotropy is growth induced and cannot be explained by conventionally accepted theories of anisotropy in garnet bubble domain materials. In preferred embodiments, these rare earth iron garnet films are deposited on suitable substances, which can be any non-magnetic materials having suitable lattice constants to provide substantial lattice match with the magnetic garnet films. Examples are Eu.sub.3 Fe.sub.5 O.sub.12 on Nd.sub.3 Ga.sub.5 O.sub.12 or (Pr,Sm).sub.3 Ga.sub.5 O.sub.12 substrates; and Sm.sub.3 Fe.sub.5 O.sub.12 on (Pr,Nd).sub.3 Ga.sub.5 O.sub.12 substrates.