Patent US 3,979,737

A magnetic film is incorporated in a device suitable for use with a computer; the film is capable of supporting magnetic bubble domains of two different sizes corresponding to stable hysteresis states which exist simultaneously under the same external magnetic field bias. When densely packed in an array, the bistable magnetic bubble domains form the basis for binary coded data storage. Single crystal garnet and amorphous intermetallic compounds may be employed as bistable bubble domain materials.