Abstract: A magnetic bubble memory structure having an enhanced storage density is made possible by reducing the circuit period, that is the distance between bubbles, in the storage section of the device. This reduction of the circuit period is made possible by using a gap tolerant propagation element, e.g. asymmetrical chevrons. The bubble storage sections are structured such that the areas closest to the transfer gates have a larger circuit period than the remainder of the storage section. The bubble chip architecture utilizing this means of enhancing the storage density may be of the major-minor loop configuration or the block-replicate configuration. Bubble storage sections in the form of loop structures may have a folded loop or an h loop configuration as well as a closed loop configuration. The reduction in circuit period accomplishes enhancement of the storage density without reducing the bubble diameter and other minimum circuit features to achieve this goal.

Abstract: An acoustic surface wave bubble switch in which a magnetic bubble domain traveling in a thin film magnetic platelet can be guided in alternate directions by application of an acoustic wave. An array of longitudinal magnetic elements in the form of single bars and bars combined to form a T configuration together with a rotating in-plane magnetic field causes the magnetic bubble to propagate across the magnetic platelet. One of the configurations of the magnetic element is a T with a second horizontal bar and the bubble will have equal attraction for either of the horizontal bars. At the proper time an acoustic wave can direct the bubble to propagate in the direction of a chosen horizontal bar thereby effecting a switching action.

Abstract: A magnetic domain memory system using single in-plane alternating magnetic fields augmented by surface elastic waves. Acoustic waveguides having bars of Permalloy elements interleaved on opposite sides of the waveguides are pulsed by surface acoustic waves generated by acoustic transducers at the ends of the waveguides. The alternating fields can be either perpendicular or parallel to the propagation direction of the magnetic domain bubbles and the interleaved Permalloy elements are positioned accordingly. Using a single alternating magnetic field, a pair of acoustic waveguides with associated surface wave transducers are configurated in loops and aligned with one having the bubble propagation direction parallel and the other perpendicular to the alternating magnetic field. Current activated transfer gates are interposed between adjacent points of the two acoustic waveguides.