Patent application number | Description | Published |
20100053795 | MAGNETIC RECORDING AND REPRODUCING APPARATUS HAVING A MAGNETIC READ HEAD WITH A SPIN-TORQUE OSCILLATOR - A magnetic recording and reproducing apparatus includes a magnetic head that has a spin-torque oscillator and a magnetic disk and the spin-torque oscillator detects a magnetic field from the magnetic disk and outputs a signal. A criterion used to determine the rotational speed of the magnetic disk, the frequency shift of the spin-torque oscillator produced by a magnetic field from the magnetic disk, a characteristic oscillation frequency of the spin-torque oscillator and the full-width at half maximum of an oscillation spectrum is given in order for a read signal output from the spin-torque oscillator to satisfy a desired signal-to-noise ratio and a magnetic recording and reproducing apparatus is configured based on the criterion. | 03-04-2010 |
20120032763 | MAGNETIC OSCILLATION ELEMENT - According to one embodiment, magnetization directions of a magnetic free layer and a magnetic pinned layer are parallel to junction planes between the magnetic free layer and a spacer layer and between the magnetic pinned layer and the spacer layer. The magnetic free layer has a uniaxial magnetic anisotropy, and generates a magnetization oscillation when a current larger than an oscillation threshold current flows through the magnetic free layer. A magnetic field generator controls a magnitude and a direction of an external magnetic field to cancel a shift amount of an oscillation frequency caused by a diamagnetic field due to the magnetization oscillation and a shift amount of the oscillation frequency caused by a magnetic field due to the uniaxial magnetic anisotropy. | 02-09-2012 |
20120218667 | MAGNETIC OSCILLATOR - According to one embodiment, a magnetic oscillator includes a layered film and a pair of electrodes. The layered film includes a first ferromagnetic layer, an insulating layer stacked on the first ferromagnetic layer, and a second ferromagnetic layer stacked on the insulating layer. The pair of electrodes is configured to apply a current to the layered film in a direction perpendicular to a film surface of the layered film. Regions having different resistance area products are provided between the first ferromagnetic layer and the second ferromagnetic layer. | 08-30-2012 |
20120224283 | THREE-DIMENSIONAL MAGNETIC RECORDING AND REPRODUCING APPARATUS - According to one embodiment, a three-dimensional magnetic recording and reproducing apparatus includes a magnetic head and a magnetic storage medium. The magnetic head includes a spin-torque oscillator including a free layer, a non-magnetic layer and a fixed layer, magnetization of the free layer being rotatable, the non-magnetic layer being laminated on the free layer, the fixed layer being laminated on the non-magnetic layer, a magnetization direction of the fixed layer being fixed. The magnetic storage medium includes first magnetic layers formed of magnetic materials having different resonant frequencies, each of the first magnetic layers being formed of an in-plane magnetization film and having recording tracks. | 09-06-2012 |
20130065086 | REPRODUCING HEAD WITH SPIN-TORQUE OSCILLATOR, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - According to one embodiment, a reproducing head includes a spin-torque oscillator and a pair of shield parts. The spin-torque oscillator has a first surface facing a magnetic recording medium. The pair of shield parts each has a second surface facing the magnetic recording medium, the spin-torque oscillator being arranged between the shield parts. A distance between the second surface and the magnetic recording medium is shorter than a distance between the first surface and the magnetic recording medium. | 03-14-2013 |
20130069730 | SPIN-TORQUE OSCILLATOR - According to one embodiment, a spin-torque oscillator includes a non-magnetic unit, one or more first magnetic unit, and a second magnetic unit. The non-magnetic unit is formed of a non-magnetic body. The one or more first magnetic unit is connected to the non-magnetic unit and generates a pure spin current indicating the flow of the electron spin that does not accompany an electric charge current. The second magnetic unit is connected to the non-magnetic unit in a manner such that a distance between the second magnetic unit and the first magnetic unit is shorter than a spin diffusion length indicating a distance that an electronic spin polarization is maintained in the non-magnetic unit. The second magnetic unit oscillates by the pure spin current. | 03-21-2013 |
20130070361 | MAGNETIC MEDIUM AND WRITING AND READING METHOD - According to one embodiment, a magnetic medium includes at least one recording layer including a first magnetic layer, a second magnetic layer and a non-magnetic layer. The first magnetic layer is form of a first magnetic material having a first magnetic anisotropy. The second magnetic layer is made of a second magnetic material having a second magnetic anisotropy different from the first magnetic anisotropy. The non-magnetic layer is made of a non-magnetic material and between the first and second magnetic layers, the first magnetic layer and the second magnetic layer being coupled such that directions of magnetization of the first and second magnetic layers are opposed to each other. | 03-21-2013 |
20130107395 | MAGNETIC HEAD, MAGNETIC SENSOR, AND MAGNETIC RECORDING/REPRODUCING APPARATUS | 05-02-2013 |
20130278346 | MAGNETIC OSCILLATOR - According to one embodiment, a magnetic oscillator includes a layered film and a pair of electrodes. The layered film includes a first ferromagnetic layer, an insulating layer stacked on the first ferromagnetic layer, and a second ferromagnetic layer stacked on the insulating layer. The pair of electrodes is configured to apply a current to the layered film in a direction perpendicular to a film surface of the layered film. Regions having different resistance area products are provided between the first ferromagnetic layer and the second ferromagnetic layer. | 10-24-2013 |
20140376129 | MAGNETIC RECORDING AND REPRODUCING APPARATUS - According to an embodiment, a magnetic recording and reproducing apparatus includes a recording medium and a reproducing head. The recording medium includes a concentric circular plurality of tracks. The reproducing head includes a spin torque oscillator and reproduces information from the recording medium using the spin torque oscillator, the spin torque oscillator including an oscillation layer with a first cross-track direction width, a polarizer layer with a second cross-track direction width, and a spacer layer provided between the oscillation layer and the polarizer layer. The first cross-track direction width is larger than double the second cross-track direction width, and the second cross-track direction width is smaller than an inter-track distance. | 12-25-2014 |