11.
    发明专利
    未知

    公开(公告)号:FR2280171A1

    公开(公告)日:1976-02-20

    申请号:FR7519003

    申请日:1975-06-12

    Applicant: IBM

    Abstract: A method of and apparatus for providing single wall self-biased magnetic domains in a film of uniaxial magnetic material. In addition to the conventional uniaxial magnetic film for supporting the single wall domains, a bias film is located adjacent thereto. The material characteristics of the two films and their thicknesses are chosen such that the exchange coupling between the two films provides the effect of an external field for supporting the single wall domains.

    CONTIGUOUS ELEMENT FIELD ACCESS BUBBLE LATTICE FILE

    公开(公告)号:CA1130001A

    公开(公告)日:1982-08-17

    申请号:CA313157

    申请日:1978-10-11

    Applicant: IBM

    Abstract: CONTIGUOUS ELEMENT FIELD ACCESS BUBBLE LATTICE FILE A bubble domain storage system is described which has the best features of contiguous element bubble propagation systems and bubble lattice file systems. An array of magnetic bubble domains, such as a lattice, is moved along contiguous propagation patterns in response to the reorientation of a magnetic field in the plane of the bubble domain film. Adjacent rows of bubble domains in the array move in opposite directions to provide individual storage loops within the array. Information accessing can be achieved by the use of input/output registers similar to those used in other contiguous disk bubble domain storage systems. For example, the storage system can be a conventional major/minor loop organization using contiguous element propagation patterns for the storage registers and for the input/output registers. Every bit position in the storage registers is populated by a bubble domain where the average distance between adjacent bubble domains is less than that in a system where bubbles are isolated from one another. For example, the storage registers can be arranged so that the separation between adjacent bubble domains in the storage registers is 2-3 bubble diameters. The bubbles are coded in terms of the magnetic properties of individual bubble domains, or a double layer structure can be used in which an array of bubble domains is in one layer and information bubble domains are in the other layer, coded in accordance with presence/ absence. Viewed another way, the invention is a bubble storage system using contiguous propagation elements which is fully populated by interacting bubble domains. YO977-032 -1-

    MINIMUM STRUCTURE BUBBLE DOMAIN PROPAGATION

    公开(公告)号:CA1068402A

    公开(公告)日:1979-12-18

    申请号:CA238129

    申请日:1975-10-20

    Applicant: IBM

    Abstract: MINIMUM STRUCTURE BUBBLE DOMAIN PROPAGATION It has been discovered that magnetic bubble domains can be moved in a magnetic medium without requiring shaped structure along which magnetic poles are created for movement of the domains, ant without reliance on magnetic fields established by conductor patterns. If a magnetic field is applied in the plane of the magnetic medium, bubble domains will be stretched in a direction parallel or anti-parallel to the field direction depending on the bubble domain polarity. If this magnetic field has an asymmetry in its amplitude versus time waveform, or if an asymmetry is created by a propagation element, bubble domains can be moved in the magnetic material. This discovery can be used to move bubble domains in a magnetic medium without requiring structure having a particular shape for domain movement, and without requiring conductors. Also, improvements can be made to existing propagation structures to make them more useful.

    14.
    发明专利
    未知

    公开(公告)号:FR2296910A1

    公开(公告)日:1976-07-30

    申请号:FR7534736

    申请日:1975-11-07

    Applicant: IBM

    Abstract: It has been discovered that magnetic bubble domains can be moved in a magnetic medium without requiring shaped structure along which magnetic poles are created for movement of the domains, and without reliance on magnetic fields established by conductor patterns. If a magnetic field is applied in the plane of the magnetic medium, bubble domains will be stretched in a direction parallel or anti-parallel to the field direction depending on the bubble domain polarity. If this magnetic field has an asymmetry in its amplitude versus time waveform, or if an asymmetry is created by a propagation element, bubble domains can be moved in the magnetic material. This discovery can be used to move bubble domains in a magnetic medium without requiring structure having a particular shape for domain movement, and without requiring conductors. Also, improvements can be made to existing propagation structures to make them more useful.

    15.
    发明专利
    未知

    公开(公告)号:DE2531722A1

    公开(公告)日:1976-02-05

    申请号:DE2531722

    申请日:1975-07-16

    Applicant: IBM

    Abstract: A method of and apparatus for providing single wall self-biased magnetic domains in a film of uniaxial magnetic material. In addition to the conventional uniaxial magnetic film for supporting the single wall domains, a bias film is located adjacent thereto. The material characteristics of the two films and their thicknesses are chosen such that the exchange coupling between the two films provides the effect of an external field for supporting the single wall domains.

    16.
    发明专利
    未知

    公开(公告)号:FR2393396A1

    公开(公告)日:1978-12-29

    申请号:FR7813282

    申请日:1978-04-27

    Applicant: IBM

    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. Any structure that can be used to provide the magnetic charged wall, including ion implanted regions of a magnetic material, or an apertured layer of magnetically soft material is suitable in the practice of this invention. The structure for providing the second magnetic field is conveniently provided by a current carrying conductor, or by a magnetic element having a stray field associated therewith, or even by another magnetic bubble domain. Thus, this invention seeks to use naturally occurring magnetic walls to assist bubble nucleation rather than using additional structure.

    METHOD OF, AND APPARATUS FOR, ESTABLISHING SELF-BIASED SINGLE WALL DOMAINS

    公开(公告)号:CA1038494A

    公开(公告)日:1978-09-12

    申请号:CA229150

    申请日:1975-06-10

    Applicant: IBM

    Abstract: A METHOD OF, AND APPARATUS FOR, ESTABLISHING SELF-BIASED SINGLE WALL DOMAINS A method of and apparatus for providing single wall self-biased magnetic domains in a film of uniaxial magnetic material. In addition to the conventional uniaxial magnetic film for supporting the single wall domains, a bias film is located adjacent thereto. The material characteristics of the two films and their thicknesses are chosen such that the exchange coupling between the two films provides the effect of an external field for supporting the single wall domains.

    18.
    发明专利
    未知

    公开(公告)号:FR2376489A1

    公开(公告)日:1978-07-28

    申请号:FR7735670

    申请日:1977-11-21

    Applicant: IBM

    Abstract: A relational data base system utilizing magnetic bubble domain storage. The bubble domain storage is located on a magnetic chip and includes storage circuitry for storing bubble domains in columns and rows. The bubble domains are coded to represent data, and the rows and columns of bubbles correspond to tables of data which are determined by various relations. Current activated transfer gates located on the magnetic chip are used to select a particular row or a particular column of bubble domains for accessing. The magnetic chip also includes a write circuit for writing bubble domains into storage and a read circuit for reading bubble domains removed from storage. Located off the magnetic chip are column addressing circuits, row addressing circuits, interface circuitry, and a computer central processing unit. The interface circuitry is located between the central processing unit and the bubble domain storage chip, while the column and row addressing circuits provide inputs to a transfer control circuit that is used to activate selected current carrying lines when it is determined to access a particular row or column of bubbles in storage. New information can be entered into any of the stored tables of bubble domains, and information can be removed from any of the stored tables. Also, new tables of information can be provided in storage by combining selected rows or columns of tables already in storage.

    GAPLESS DOUBLE-SIDED PROPAGATION STRUCTURE FOR BUBBLE DOMAIN DEVICES

    公开(公告)号:CA1033840A

    公开(公告)日:1978-06-27

    申请号:CA213253

    申请日:1974-11-07

    Applicant: IBM

    Inventor: LIN YEONG S

    Abstract: Gapless, double-sided propagation structures are provided for implementing the continuous movement of magnetic bubble domains under the control of a reorienting in-plane field. Propagation is achieved by using two identical disc circuits on both sides of the bubble material displaced from each other by one-half of periodicity. The discs in each circuit are disposed in tangential engagement with each other and the two circuits may follow any desired path provided the circuits are in alignment with each other.

    CONPENSATION OF DEMAGNETIZING EFFECTS IN MAGNETORESISTIVE SENSING

    公开(公告)号:CA943665A

    公开(公告)日:1974-03-12

    申请号:CA154654

    申请日:1972-10-24

    Applicant: IBM

    Abstract: 1369573 Magnetic storage devices INTERNATIONAL BUSINESS MACHINES CORP 28 Sept 1972 [26 Oct 1971] 44737/72 Heading H3B A sensor of small magnetic fields, such as bubble domains, comprises a magneto-resistive element whose dimensions are sufficiently small, e.g. 200 angstroms thick, 7À5 microns long and 5 microns wide, as to have both a uniaxial anisotropy field imparted during manufacture, and a shape anisotropy field determined by the relationship of its unequal length and width dimensions, the two anisotropy fields being mutually perpendicular and the larger of the two fields being substantially perpendicular to the magnetic field to be detected. As shown in Fig. 1A, a rectangular magnetoresistive element 18 is associated with an orthoferrite or garnet sheet 10 in which bubble domains are propagated by the combination of a permalloy T and I bar pattern and an in-plane rotating magnetic field H. A rectangular magnetoresistive sensor element 18 formed, e.g. of permalloy; and located on or adjacent to the sheet 10, is connected to a constant current source 20 by leads 19, changes of resistance due to magnetic field proximity being indicated to a utilization means 22 as a change of voltage Vs. The sensor element has an easy axis of magnetization E.A. transverse to its length, and has a shape anisotropy field greater than the uniaxial anisotropy field so that the magnetization vector M is normally directed along the length of the element. When a bubble domain 30, Fig. 1B, is moved into a position adjacent the sensor element 18, the external field H B of the domain coupled with the element causes rotation of its magnetization vector M and consequential change in the element resistance. It is stated that the use of both uniaxial and shape anisotropy enhances the detection sensitivity to small magnetic fields. In a modification. Figs. 2A and 2B, the sensor element is arranged so that it is parallel to an external domain field H B along its length dimension. As before the easy axis of magnetization E.A. extends across the width of the element, but in this case the shape anisotropy field is less than the uniaxial anisotropy field so that the normal position of the magnetization vector M is parallel to the easy direction of magnetization. This vector is rotated towards the length dimension of the element by an adjacent bubble domain 30 as shown in Fig. 2B. The sheet 10 is subjected to a bias field H z derived from a permanent magnet, an energized coil or an adjacent magnetic sheet. The sensor may be used to read out a pattern of domain reversals extending across a moving magnetic tape, Fig. 3A (not shown), in which case the sensor element is mounted with electrical connections on an insulating substrate. Such an element is formed by evaporation deposition on a magnetic sheet or insulating substrate in the presence of a magnetic field with the subsequent selective formation of electrical connections by masking, electroplating and etching.

Patent Agency Ranking