Logic functions for magnetic bubble devices

Abstract

An analysis has been made of the number and types of logical functions which can be performed using the interaction of circular magnetic domains in rare earth iron oxides. Multiple logic functions are found to be produced simultaneously at any logical area. These conjunctive output sets have been categorized. Several conjunctive logic gates have been designed, fabricated, and tested successfully in Sm <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.55</inf> Tb <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.45</inf> FeO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> using Permalloy overlays. Utilizing a circuit in which AND/OR logic gates are coupled to a dynamic memory bank, the total correlation of two data streams has been performed. It is shown how this multiply accessed dynamic memory serves to establish the correlation threshold.