Magnetic domain logic device

Abstract

A magnetic device comprising a first and a second plate of a magnetic material between which domains are situated. An interaction force occurs between the domains in the two plates. Stable domain positions in a second plate define equally stable domain positions in a first plate. One or both plates can be provided with domain guiding structures. Domain displacement in one plate can control a domain displacement in the other so that a variation in the interaction force is produced.

What is claimed is: 
     
       1. A magnetic device comprising a first plate of a magnetic material in which at least one domain is present, a domain guiding structure having a plurality of continuous branched connecting paths for the displacement of the domain in the first plate, a second plate of magnetic material in which a domain is present, said second plate covering, at least in projection, at least a part of the first plate, an interaction force occurring between at least one domain in the first and one domain in the second plate, and a domain guiding structure having at least one path for the displacement of a domain in the second plate which controls the displacement of the domain in the first plate along one of saaid paths therein. 
     
     
       2. A magnetic device as claimed in claim 1 including means to vary the distance between the plates whereby the dimensions of the domains can be varied. 
     
     
       3. A magnetic device as claimed in claim 1 including means to vary a dimension of a domain in the second plate whereby the domain is displaceable in the direction of the guiding structure. .Iadd. 
     
     
       4.  A magnetic device comprising a first plate of a magnetic material in which at least one domain is present, a domain guiding structure having a plurality of guiding paths for the displacement of domains in the first plate, and a second plate of magnetic material completely filled with domains, said second domain covering, at least in projection, at least a part of the first plate, an interaction force occurring between at least one domain in the first and one domain in the second plate, the domains in the second plate creating stable positions for the domains in the first plate. .Iaddend. .Iadd.5. A magnetic device as claimed in claim 4 including a domain guiding structure for displacing domains in the second plate according to a given trajectory, said displaceable domains in the second plate defining displaceable stable domain positions in the first 
     
     
        plate. .Iaddend. .Iadd.6.  A magnetic device as claimed in claim 5 wherein the guiding structure in the second plate is a closed loop. .Iaddend. .Iadd.7. A magnetic device as claimed in claim 4 including domain guiding structures for displacing domains in the first and second plate according to given trajectories, a displacement of a domain in the second plate causing and controlling a displacement of domains according to one of the trajectories in the first plate. .Iaddend. .Iadd.8. A magnetic device as claimed in claim 4, wherein said first and second plate are displaceable with respect to each other so that the dimensions of the domains in the plate can be varied. .Iaddend. .Iadd.9. A magnetic device as claimed in claim 4, including a structure for guiding domains in at least one of the plates, and said first and second plate are displaceable with respect to each other, a domain being displaceable in the direction of said guiding structure as a result of a dimensional variation of a domain. .Iaddend. 
     
     
        .Iadd.10.  A magnetic device as claimed in claim 4 wherein the second plate comprises a strip domain by which stable domain positions are defined in the first plate at the area of the projection of the ends of 
     
     
        said strip domain. .Iaddend. .Iadd.11.  An apparatus using magnetic bubble domains comprising: a first magnetic medium containing a lattice of magnetic bubble domains; and   a second magnetic medium containing an information bit pattern of bubble domains and the absences of bubble domains, said second magnetic medium being arranged near and over the first magnetic medium so that the bubble domains in the second magnetic medium are magnetically coupled to bubble domains in the first magnetic medium, movement of the lattice of bubble domains in the first magnetic medium thereby causing movement of the information bit pattern of bubble domains in the second magnetic medium by   
     
     
        said magnetic coupling. .Iaddend. .Iadd.12.  An apparatus using magnetic bubble domains, comprising: a first magnetic medium and confinement means for confining domains therein in a two-dimensional lattice of interacting bubble domains, the interdomain spacings in said lattice being substantially determined by interactions between said domains and by said confinement means,   a second magnetic medium,   means for producing an information bit pattern of bubble domains and voids in said second magnetic medium in positions where said bubble domains in said second magnetic medium are magnetically coupled to bubble domains in said first magnetic medium, the spacings between said bits in said second medium being substantially determined by the interdomain spacings in said lattice,   means for moving said bubble domains in said information bit pattern, comprising further means for moving domains in said lattice to thereby move said information bit pattern of domains by said magnetic coupling, and   means for sensing said bubble domains in said second magnetic medium. .Iaddend. .Iadd.13. An apparatus using magnetic bubble domains, comprising:   a first magnetic medium and a confinement means for confining a two-dimensional lattice of columns of magnetic bubble domains therein, the positions of bubble domains within said lattice being substantially determined by interactions therebetween, and by said confinement means,   a second magnetic medium with a coded pattern of magnetic bubble domains therein which are magnetically coupled to domains in said lattice, each said domain in said coded pattern being coupled to a different one of said domains in said lattice,   means for moving columns of bubble domains in said lattice, to thereby drag columns of magnetically coupled bubble domains in said coded pattern,   means for producing said coded patten of bubble domains in said second magnetic medium,   means for sensing bubble domains in said coded pattern of bubble domains. .Iaddend.