System and method for reading data stored on a magnetic shift register
AssigneeInternational Business Machines Corporation
InventorStuart S. P. Parkin
Life of this patent
Estimating the term…
Abstract
A reading device reads the direction of the magnetic moment of domains in a magnetic shift register, thus reading information stored in the domains or bits in the magnetic shift register. Associated with each domain wall are large magnetic fringing fields. The domain wall concentrates the change in magnetism from one direction to another in a very small space. Depending on the nature of the domain wall, very large dipolar fringing fields can emanate from the domain wall. This characteristic of magnetic domains is used to read data stored on to the magnetic shift register. The reading device reads the direction of the magnetic moment in a magnetic shift register, thus reading information stored in the domains.
Claims52
A data reading device, comprising:
- a magnetic tunneling junction comprising layers of magnetic material selected from the group consisting of ferromagnetic material and ferrimagnetic material, wherein at least some of the layers of magnetic material are separated by at least one insulating layer;
- a magnetic medium comprising at least one domain having domain walls;
- wherein an electric current is passed through the magnetic medium to selectively shift the domain walls in a direction of the electric current;
- and
- wherein data stored in the domain is selectively read by disposing the magnetic tunneling junction in proximity to a fringing magnetic field from one of the domain walls, and by using the fringing magnetic field to detect a magnetic moment of the domain.
A method of making a data reading device, comprising:
- forming a magnetic tunneling junction by providing layers of magnetic material selected from the group consisting of ferromagnetic material and ferrimagnetic material;
- separating at least some of the layers of the magnetic material by at least one insulating layer;
- forming a magnetic medium comprising at least one domain having domain walls;
- wherein an electric current passing through the magnetic medium selectively shifts the domain walls in a direction of the electric current;
- and
- wherein data stored in the domain is selectively read by disposing the magnetic tunneling junction in proximity to a fringing magnetic field from one of the domain walls, and by using the fringing magnetic field to detect a magnetic moment of the domain.
A method of reading data stored on a data storage device that comprises a magnetic tunneling junction formed of layers of magnetic material selected from a group consisting of ferromagnetic material and ferrimagnetic material, wherein the layers of magnetic material are separated by at least one insulating layer;
- and a magnetic medium comprising at least one domain having respective domain walls, the method comprising:
- selectively reading data stored in the domain by disposing the magnetic tunneling junction in proximity to a fringing magnetic field from one of the domain walls
- passing an electric current through the magnetic medium to selectively shift the domain walls in a direction of the electric current;
- and
- using the fringing magnetic field to detect a magnetic moment of the domain.
Dependencies are inferred from the claim text.