Bistable magneto-optic single crystal films, as well as a method for their preparation by controlled introduction of defects

摘要

A bistable single crystal magneto-optic film of preselected coercivity is described. The film is readily switchable and is characterized by a substantially square shaped hysteresis loop. The film properties are attributed to controlled introduction in the film of defects of predetermined size and distribution. Defects of from about 0.4 mu m to about 4.0 mu m present in numbers per cm2 of from about 10 to about 106, with optimal distribution falling in the range of from about 100 to about 1000, are described. Also described are methods of achieving the required defect size and distribution utilizing procedures such as ion bombardment, particle abrasion/deposition, laser ablation or annealing of the film or substrate upon which the film is supported. Devices in which the films can be used to advantage, such as flaw detecting, imaging and microwave processing, are described.