Abstract: A magnetic circuit in one aspect comprises a plurality of tapered magnetic wires each having a relatively wide input end and a relatively narrow output end, with the output end of a first one of the tapered magnetic wires being coupled to the input end of a second one of the tapered magnetic wires. Each of the tapered magnetic wires is configured to propagate a magnetic domain wall along a length of the wire in a direction of decreasing width from its input end to its output end. In an illustrative embodiment, the magnetic circuit comprises a logic buffer that includes at least one heating element. The heating element may be controlled to facilitate transfer of a magnetic moment from the output end of the first tapered magnetic wire to the input end of the second tapered magnetic wire.

Abstract: Systems and methods are provided for digital transport of paramagnetic particles. The systems and methods may include providing a magnetic garnet film having a plurality of magnetic domain walls, disposing a liquid solution on a surface of the magnetic garnet film, wherein the liquid solution includes a plurality of paramagnetic particles, and applying an external field to transport at least a portion of the paramagnetic particles from a first magnetic domain wall to a second magnetic domain wall of the plurality of magnetic domain walls.

Abstract: A magnetic logic element for a logic device is described formed by at least one conduit capable of sustaining and propagating a magnetic soliton, the conduit being adapted by the provision of nodes and/or directional changes giving rise to discontinuities in soliton propagation energy as a result of which logical functions may be processed. Magnetic logic devices such as interconnects and gates, and magnetic logic circuits incorporating such devices and suitable operational fields, are also described.

Abstract: A logic device formed at least one chain of dots of magnetic material. Each dot has a width of 200 nm or less and is spaced at a distance that is sufficiently small to ensure magnetic interaction of adjacent dots.

Abstract: The present invention provides a method and apparatus for adapting to noise sources affecting a pulse oximeter. Various available frequencies are evaluated to determine their respective noise levels and one is selected to act as the operating demultiplexer frequency. During normal operation of the pulse oximeter, the various available demultiplexer frequencies are periodically scanned to determine which has the lowest associated noise. The noise level associated with the operating frequency is used to determine the signal-to-noise ratio of the pulse oximeter signals and thereby qualify certain signals from the pulse oximeter. Those pulses associated with a signal-to-noise ratio below a predetermined threshold are rejected and excluded from use in calculating blood oxygen saturation.

Abstract: Herein disclosed is a laminated magnetic bubble device of a multiple layer structure composed of at least one thin magnetic film having low coercive force and vertically oriented anisotropy which can allow easy generation and erasure of a magnetic bubble, and at least one thin magnetic film having high coercive force and vertically oriented anisotropy which will not be affected by a magnetic field of low level used for generating the magnetic bubble in the thin film of low coercive force.

Abstract: A memory device utilizing magnetic bubbles which are driven by a rotary magnetic field on contiguous disc drive patterns. These disc patterns have mainly a first scale. Each drive pattern also comprises a further disc pattern of a substantially larger scale. These further disc patterns each time comprise an excitation loop. These loops are mutually staggered with respect to the phase of the rotary field and are electrically connected in series. The series connection can be excited during relevant phases of the rotary magnetic field in order to selectively process a bubble then present in a locally formed preferred position from among the magnetic bubbles present on the larger disc patterns. The processing operation may be generating, detecting and annihilating bubbles.

Abstract: A magnetic bubble domain system including a planar layer of magnetic material in which magnetic bubble domains can be propagated; and first and second bubble domain guide structure coupled to the layer and defining respective first and second bubble propagation paths for guiding the movement of bubbles in the layer in response to a cyclical change in the orientation of a reorienting magnetic field within the plane of the layer. A transfer bubble domain guide structure coupled to the layer is also provided for transferring bubble domains between the first and the second propagation paths responsive to a reverse in direction of the reorienting magnetic field. The transfer path is substantially the same as one of the directions of the crystallographic axes of the planar layer.

Abstract: A magnetic bubble memory device comprises: a magnetic layer which has a first region having the easy axis of magnetization extending in a certain direction and a second region surrounding said first region and having the easy axis of magnetization substantially perpendicular to that of the first region, said first region defining at least one major loop pattern for propagation of information bubbles and a plurality of minor loop patterns for storage of information bubbles; and an electrical conductor pattern deposited on said magnetic layer in a region in which the major loop pattern and the minor loop patterns are opposed to each other, thereby constructing a transfer gate. The major loop pattern is provided, at the portions thereof substantially opposed to the ends of the minor loop patterns in the transfer gate, with gaps through which the bubbles are transferred between the major loop pattern and the minor loop patterns. The transfer gate is driven by means of a convex-shaped pulse of transfer current.

Abstract: A bi-level magnetic bubble domain propagation structure in which the domain guide structure is formed by a spatially periodic pattern of permalloy implemented on two discrete levels separated by a substantially vertical gap. The structure forms a pattern of contiguous disk on one level and the complementary image of such disks on the second level.

Abstract: A bubble domain replicator for ion-implanted contiguous disk devices has a cusp portion and a tip portion extending substantially away from the cusp portion so that the cusp forms part of a super track and the tip forms part of a bad track. A hairpin conductor is positioned over the cusp portion and tip portion so that the closed end of the hairpin is closest to and surrounds the end of the tip portion.

Abstract: A replicator for a magnetic bubble domain device including a hairpin loop conductor element traversing first and second spaced apart bubble domain guide structures. The replicator functions to replicate a bubble domain travelling along the first bubble propagation path onto the second bubble propagation path in response to an activating signal on the conductor. The replicate guide structure includes two attractive cusp positions and one repulsive cusp position, so that the repulsive charged wall formed at the repulsive cusp position functions to sever a stretched bubble domain formed by the activating signal.

Abstract: A bubble memory chip includes a plurality of data loops, some of which may be defective, for storing magnetic bubbles representative of data therein. A serial-parallel input propagation path and a parallel-serial output propagation path are provided for propagating bubbles to and from the data loops. A plurality of spaced apart permalloy disk elements are provided, each adapted for having a single bubble circulated thereabout in the presence of an in-plane rotating magnetic drive field. A stream of bubbles representative of an error map indicating which of the data loops are defective is loaded onto and read from the disk elements to initialize the memory. A plurality of gates permit the bubbles of the error map to be transferred between an error map propagation path and the disk elements in parallel fashion upon pulsing of an adjacent control conductor. The potential for data scrambling in the error map is eliminated.

Abstract: Amorphous ferrimagnetic layers are described with support stable and mobile magnetic charged walls. These layers can be used as drive layers in magnetic bubble domain devices, and are characterized by very weak even-fold in-plane anisotropy, or substantially zero in-plane anisotropy. The layers are metallic alloy compositions having magnetic properties that can be tailored over wide ranges, and are particularly suitable as drive layers for the propagation of bubble domains of extremely small diameters.

Abstract: A bubble storage system using contiguous propagation elements is described using magnetically soft drive layers for movement of the bubble domains in a bubble domain film, in response to the reorientation of a magnetic drive field in the plane of the drive layers. In contrast with prior art contiguous element propagation structures, charged walls are not employed for movement of bubble domains. Instead, magnetic poles along the drive layers are used to move the domains. Two drive layers are used, each of which is comprised of a magnetically soft material, such as permalloy. The drive layers are located at different heights with respect to the layer in which the magnetic bubble domains exist, the bottom drive layer being comprised of contiguous propagation elements defining a generally undulating edge along which the magnetic bubble domains move. This layer can be comprised of permalloy contiguous disks, diamonds, etc.

Abstract: A close-packed magnetic bubble propagation device includes a pattern having a plurality of propagation elements positioned in at least four adjacent rows. These elements are spaced to provide a period or spacing of bubbles in these rows of less than three bubble diameters. Upon application of a rotating in-plane field to the elements, bubbles in adjacent rows move in opposite directions. A preferred embodiment of this propagation device has at least two storage loops which contain at least four adjacent horizontal rows of propagation elements. A preferred device utilizing this pattern has at least two storage loops and an access path which passes through each of the loops. An electrical conductor is associated with the propagation elements in the access path so that the passing of a current through the conductor together with the application of an in-plane rotating field to the elements causes bubbles associated with the elements in the access path to move along the access path.

Abstract: The invention is directed to continuous (gapless) propagation structures for use with magnetic bubble domain devices. The gapless structures are arranged so that magnetic bubbles will propagate therealong without a significant change in size or diameter of the bubble. In addition, the structures are configured so that the bubbles will propagate in a preferred direction without ambiguity.

Abstract: A replicator for an ion-implanted magnetic bubble memory includes an offset hairpin geometry. The conductor is associated with features in adjacent bubble paths which exhibit strong attracting poles at the same time. The conductor stretches the bubble between the attracting poles. The bubble is severed by the reorienting propagation field.

Abstract: A magnetic bubble memory of the G-shaped organization is implemented by ion-implantation. Attractive operating margins are realized by the use of transfer-out arrangements which moves bubbles in parallel first to an auxiliary path and thereafter to the major loop in a manner to invert the data.

Abstract: A magnetic device comprising at least one thin domain layer of a magnetizable material which has an easy axis of magnetization which is substantially normal to the surface of the layer and in which magnetic domains are propagated under the influence of a bipolar current, for example an alternating current, by a pattern of electrically conductive material with which the layer is provided. Elements are furthermore present which cause an asymmetry force and thus determine the direction in which the domains are propagated. The electrically conductive material and the elements are present in a single pattern which is constructed from at least a layer of magnetic material.

Abstract: In a display unit utilizing magnetic bubbles, selective extinction of the magnetic bubbles in a matrix results in a pattern of letters and/or images which are combinations of the magnetic bubbles as picture elements. The present display unit has in-plane anisotropic areas each of which has an easy magnetization axis parallel to the surface of the magnetic bubble material thin film produced by attaching the magnetically soft thin film on the magnetic bubble accommodation spaces in the magnetic bubble material thin film or by ion-implanting into the given spaces of the magnetic bubble material garnet. Therefore, according to this invention, the domain walls of the magnetic bubbles are attracted to said in-plane anisotropic areas and securely held at predetermined picture element positions.

Abstract: A magnetic bubble device comprising a non-magnetic substrate layer, and a sequence of magnetic layers joined to each other and to the magnetic substrate layer, e.g. by epitaxial growing of crystalline layers, whereby at least two of the magnetic layers may accommodate magnetic bubbles which are stably joined through an interlayer magnetic compensation wall, or by an essentially finite potential barrier.

Abstract: An associative magnetic domain memory comprising; a predetermined number of storage loops having a predetermined number of magnetic elements on which domains circulate, said domains or absence of said domains on said magnetic elements in said storage loops representing bits of binary information; write-in section and read-out means disposed relative to said storage loops; said write-in section including, generator for generating bits and propagating said bits to positions adjacent said storage loops as a set of bits with a subset of said bits representing address bits and the rest of said set being data bits, and a gate for transferring said set of bits into said storage loops for storage therein; said read-out section including a replicator for forming replicas of sets of bits in said storage loops, a gate for transferring said replica sets one at a time, a sensor for receiving and sensing said transferred replica sets if one of said address bits does not match the desired address criteria.

Abstract: A conductor-access, magnetic bubble memory is realized with a single metallization level for propagation. The familiar undulating or serpentine conductor pattern used for moving bubbles is modified to allow a simple and easily realizable, low power drive arrangement where currents flow parallel to the bubble paths.

Abstract: An improved magnetic bubble domain nucleator is provided which uses a magnetic wall, such as a charged wall, Neel wall, or Bloch wall, to assist nucleation. In a preferred embodiment, a magnetic charged wall is produced in an ion implanted region of a magnetic material with an in-plane magnetic field, and an applied nucleating magnetic field is produced by current in a conductor. The combination of the first magnetic field associated with the charged wall and the second magnetic field produced by current through the conductor is sufficient to nucleate a bubble domain in the magnetic medium whereas each of these fields acting alone is not sufficient for nucleation. Since the first magnetic field provides a component of the total nucleating field, the amount of nucleation current required in the conductor is reduced.

Abstract: An apparatus for and a method of moving stripe domains in a direction transverse their length is disclosed. The apparatus includes a layer of magnetizable material in which stripe domains are capable of being generated, sustained and moved. Formed upon the magnetizable layer are two parallel contiguous disk files, each of which is formed of a plurality of linearly aligned similar contiguous Bicore disks. Each Bicore disk is comprised of a disk of a relatively soft magnetizable material, e.g., Permalloy, and a superposed disk of a relatively hard magnetizable material, e.g., Cobalt, sandwiching an insulative layer, e.g., silicon dioxide, SiO.sub.2, therebetween.

Abstract: There is provided a memory system, for example, a magnetic bubble domain memory, which includes an exchange stack buffer memory between a main storage area and other portions of a bubble domain chip organization. The buffer memory includes a plurality of magnetic areas, such as discs, arranged in an ordered array between the main storage area and the remainder of the chip organization. Control conductors are arranged to interconnect each row of magnetic areas with an adjacent row of similar areas, or with portions of the main storage area, or with the remainder of the chip organization circuit. Means are provided to supply signals to the control conductors to selectively transfer information from a row of magnetic areas to one of the adjacent areas.