Abstract: A rotating field access pattern for use in the propagation of a bubble lattice is disclosed. The pattern contains two sets of parallel oblong elements that are substantially perpendicular to each other. Four specific permalloy patterns featuring one element per one, two, two and four bubble domains are shown.

Abstract: A rotating field access pattern for use in the propagation of a bubble lattice is disclosed. The pattern contains a set of diamond shaped magnetic elements arranged in a regular array. The elements have two sides which are parallel to one bubble lattice axis and two sides which are parallel to another bubble lattice axis. The bubbles are propagated in the direction of a third bubble lattice axis.

Abstract: Polymeric compositions containing a ##STR1## group are disclosed.

Abstract: Permalloy type alloys containing rhodium suitable for use in magnetic devices and having improved resistance to corrosion contain from about 65 to 90 atomic percent nickel, 10 to 35 atomic percent iron and 1 to 25 atomic percent rhodium. Magnetic films made of these alloys which contain 1 to 10 atomic percent rhodium exhibit magnetic properties similar to Permalloy while having increased resistance to corrosion.

Abstract: A bubble lattice translation system is disclosed. The system is a combination of two arrays of parallel conductors and confining means. One array of parallel conductors is oriented at an angle of 60.degree. to the lattice translation axis. All of these conductors in this array are connected in parallel to a single current source. The other array of conductors is at an angle of -60.degree. to the lattice translation axis. All of the conductors in the second array are connected in parallel to a second current source. The two conductor arrays exist in the same plane of metallization with no insulation required at conductor intersections. Positioned between the rows of bubbles in the lattice are confining means which define the lattice translation axis. The two conductor circuits are activated sequentially by bi-polar current drivers such as two sinusoidal current sources which are 90.degree. out-of-phase.

Abstract: A method of forming a serrated surface topography useful for the unidirectional propagation of magnetic domains is disclosed. The method includes the step of forming a substantially rectangular wave topograhy on the surface of the structure and subsequently ion milling the rectangular wave topography at an oblique angle of incidence to form the serrated surface topography.

Abstract: A system suitable to transfer a bubble domain from one field to a second field where the field is the largest area formed by exposing a pattern and which all of the dimensions are critical is disclosed. A magnetic domain is propagated out of the first field through an outlet into an inlet of the second field. In a preferred embodiment, the width of the outlet is one to ten bubble diameters and the width of the inlet opening is two to ten bubble diameters, the inlet opening being always at least as wide as the outlet opening. Associated with the inlet opening is a contracting means, for example, a Chevron pattern of decreasing height, which reduces the size of the domain to a size suitable for use in the bubble system in the second magnetic field.

Abstract: Magnetic domains with defined wall topologies are controllably generated from a domain having known characteristics. A "mother" bubble domain of a known wall state is generated by nucleation. The mother domain is stretched and split in the presence of a magnetic field directed across the separation area. A pair of Bloch lines is generated in every splitting process. The assignment of the lines to either one of the two resulting domains depending upon the wall state of its mother domain and the direction of the directed magnetic field. Instead of the directed magnetic field, velocity inducing forces can be applied to the elongated domain. The effect desired is to incline the wall magnetization in the elongated section of the domain. Controlled resplitting of domains having Bloch lines increases the number of Bloch lines in one domain to generate any predesignated wall state. The multiplicity of states which can be controllably generated anticipates their utilization beyond binary bit coding.

Abstract: A bubble lattice structure is disclosed containing a barrier positioned between at least two adjacent rows of bubble domains and/or stripe domains. More than one barrier may be utilized to retain integrity of the lattice. The bubble lattice structure containing barriers has a number of advantages or improved operating characteristics such as better control in maintaining the relative position of the bubble domains in the lattice columns adjacent the column of bubbles being accessed, closer control of the number of rows of bubbles in a given area, and a reduction of the distortion of the lattice during lateral translation.

Abstract: A beam addressed liquid crystal cell having an absorbing layer adapted to absorb energy in the infrared spectrum while transmitting substantial energy in the visible spectrum is disclosed. In a preferred embodiment the absorbing layer contains the reaction product of bis (dithiobenzil) nickel and a polyamide. This absorbing layer absorbs at least 90% of the gallium arsenide laser wavelengths and at the same time permits transmission in the visible spectrum to be of the order of 80%.

Abstract: A magnetic layer is exchange coupled to a bubble medium in an area where bubble domains are nucleated, and is used together with or without an externally applied in-plane magnetic field to controllably generate bubble domains with either one pair (S = 0) or no Bloch lines (S = 1), respectively. The exchange coupled magnetic layer can be either an ion-implanted layer, a thin garnet film with planar magnetization, or a thin permalloy film. The exchange coupled magnetic layer may be positioned either on top of or below the bubble film used for storage. An information store utilizing domain interaction for bubble domain storage such as lattice array is accomplished by having each bubble domain representing either binary bit according to its domain wall state.

Abstract: Stationary patterns of magnetic domains in a film layer of magnetically hard material define local field gradients for movement control of single-wall domains located in a contiguous sheet of magnetic "bubble" material. Suitable patterns of uniformly magnetized regions are established in the hard-magnetic film to provide the control pattern. A second garnet film of suitable composition, for instance, may be grown epitaxially on the bubble medium to provide the hard magnetic control film. Bubble domain confinement and propagation patterns are established in the hard-magnetic film by conventional recording methods or the desired pattern can be generated by projection or scanning the pattern with a light beam or an electron beam, or by thermomagnetic transfer from a master pattern.

Abstract: A method of providing an initial lattice containing magnetic bubble domains in a film is disclosed. The method includes a first step of providing a confinement area in a film to contain magnetic domains, a second step of applying an AC in-plane magnetic field to form a plurality of rows of substantially perfect parallel stripe domains, and a third step of cutting the stripe domains into bubbles to form a substantially perfect lattice containing bubble domains.

Abstract: A method of polarizing nuclei having a long relaxation time in a solid in a high DC magnetic field. The solid also contains nuclei having a short relaxation time. The method involves the step of applying a high DC magnetic field to the solid. Then the solid is swept with a radio frequency field which excites the nuclei with a short relaxation time thereby resulting in the polarization of the nuclei having a long relaxation time.

Abstract: A closed loop bubble lattice system and a method for stabilizing the same is disclosed. The closed loop bubble lattice system contains at least one portion being curved wherein the lattice parameter increases with the radius. In a preferred embodiment a radially varying bias field is associated with the curved portion in a manner to provide an equilibrium lattice constant at a bubble domain position which is substantially the same as the lattice parameter for that position. A method of reducing the stress in the curved portion of the bubble domain lattice system to provide stabilization therefor involves the step of varying one or more of the parameters which affect the equilibrium lattice constant.

Abstract: A wall topology storage system wherein information in the form of data bits is stored as polarity reversals in magnetic domain walls separating adjacent magnetic domains. A plurality of bits is stored in each wall as a plurality of reversals, resulting in greater storage capacity than when using the adjacent domain itself.