Rotational remagnetization of thin films

THE THIN FERROMAGNETIC film is an adaptation of the familiar magnetic memory core to (or toward) the millimicrosecond speed range. Its most evident advantages arc that its simple configuration permits a homogeneous rotation of the magnetization without running afoul of demagnetization problems, which enormously complicate and slow down the switching of toroidal cores; that it reduces the eddy-current problems in the metals, from which, unfortunately, it has alone been possible to fabricate practical elements; and that it is, in principle, easy to fabricate and to miniaturize. The more incisive reasons dictating a thin film geometry, and the unique influence of the shape on the underlying physical mechanisms, will be indicated below.