Abstract: A magnetic memory device comprises a magnetic tunnel junction (MTJ) connecting to a bit line to a sense line through an isolation transistor. The MTJ includes a ferromagnetic layer having a magnetic hard axis. An assist current line overlies the bit line and is insulated from the bit line. The MTJ is switchable between a first, relatively high resistance state and a second, relatively low resistance state. The assist current line applies a magnetic field along the magnetic hard axis in the ferromagnetic layer, independently of current flow through the MTJ for assisting switching of the MTJ between the first and second states.

Abstract: In MRAM using a spin-transfer torque switching, a sufficient writing operation with a small memory cell is realized, and a reading current is enlarged while a reading disturbance is suppressed. In the case where the free layer of the tunnel magneto-resistance element is located on the side of the bit line, using a PMOS transistor, and in the case where the fixed layer of the tunnel magneto-resistance element is located on the side of the bit line, using an NMOS transistor, an anti-parallel writing in a source grounding operation is performed. The reading and writing operation margin is improved by performing a reading operation in an anti-parallel writing direction.

Abstract: In a memory using spin transfer torque, state of the spin is made unstable by applying a weak pulse before rewriting to reduce rewrite current. Reading of high-speed operation is performed with current in a regime where the current becomes non-linearly increases corresponding to the pulse width to suppress disturb. Further, fluctuation of respective memory cells is suppressed by a driving method setting the amount of spin constant by bit line charge to suppress read disturb.

Abstract: A magnetic memory device comprises a magnetic tunnel junction (MTJ) having a ferromagnetic free layer, and exhibits a first, relatively high resistance state, and a second, relatively low resistance state. To write to the magnetic memory device a current IMTJ is driven through the MTJ. For a first duration, the current is equal to a DC threshold current, being the DC current required to switch the multilayer structure between the first state and the second state. This induces a C-like domain structure in the free layer. For a second duration, the current IMTJ is larger than the DC threshold current. This causes the MTJ to switch states. The current requited to cause switching is less than that required using a uniform current pulse.

Abstract: A magnetic recording device which can write magnetic information with high density. The device uses, for a magnetic recording layer of a magnetic recording medium, a magnetic material whose anisotropy energy varies with an applied electric field. The head has an electrode for applying an electric field to a recording area of the magnetic recording medium. Magnetic recording is performed by applying an AC electric field from the electrode while a DC magnetic field is applied to the recording area of the magnetic recording layer.

Abstract: A magnetic recording device which can write magnetic information with high density. The device uses, for a magnetic recording layer of a magnetic recording medium, a magnetic material whose anisotropy energy varies with an applied electric field. The head has an electrode for applying an electric field to a recording area of the magnetic recording medium. Magnetic recording is performed by applying an AC electric field from the electrode while a DC magnetic field is applied to the recording area of the magnetic recording layer.

Abstract: A perpendicular magnetic recording medium for thermo-magnetic printing has an ultra-high recording density and is resistant to thermal decay of magnetization. An intermediate layer of the medium is provided between a first recording layer using a low-noise Co alloy ferromagnetic substance and a second recording layer using a ferrimagnetic substance (e.g., a rare-earth element-transition metal compound) having a compensation temperature below an operation ambient temperature. A magnetic field is applied thereto to form a magnetization pattern on the first recording layer. It is then heated-up to be printed onto the second recording layer, which has a higher coercivity at the ambient temperature, and a recording field is suitably set to form a magnetization pattern only on the first recording layer. The magnetization pattern is printed from the first recording layer to the second recording layer.

Abstract: A magnetic head includes a first electrode layer, a first ferromagnetic electrode pair that is electrically connected to the first electrode layer, and a second ferromagnetic electrode pair that intersects with a current which flows between the first ferromagnetic electrode pairs and is electrically connected with the first electrode layer. The current is allowed to flow between the first ferromagnetic electrode pair through the first electrode layer to accumulate spin electrons in the first electrode layer. A direction of magnetization of the fourth ferromagnetic electrode layer changes upon application of an external magnetic field. The second ferromagnetic electrode pair is so arranged as to intersect with the current that flows between the first ferromagnetic electrode pair, to increase a rate of change in the output signal of the in-plane spin accumulation effect.

Abstract: Disclosed is a magnetic memory apparatus which comprises a patterned magnetic recording medium in which multilayered films each having a first magnetic layer, a nonmagnetic metal layer or a nonmagnetic insulating layer and a second magnetic layer deposited discretely on a conductive electrode layer formed on a substrate, and a cantilever array having a plurality of cantilevers each having a conductive chip at its distal end. This provides a magnetic solid memory apparatus that has a large memory capacity and a super fast transfer rate, the merits of a hard disk apparatus, and a nanostructure and low power consumption, which are the merits of a semiconductor memory.

Abstract: A magnetic head using a tunneling magnetoresistance effect realizing both high output and wide bandwidth. By providing a magnetic read head and magnetic reading/playback apparatus related to the present invention characterized by comprising: a lower magnetic shield, an upper magnetic shield, a first electrode layer formed on said lower magnetic shield, a first ferromagnetic layer laminated on one end of said first electrode layer through a first insulator, a second ferromagnetic layer laminated on another end of said first electrode layer through a second insulator, a detecting electrode connected to said first ferromagnetic layer, and a second electrode layer electrically connecting said second ferromagnetic layer with said upper magnetic shield; it becomes possible to reduce the capacitance between the first ferromagnetic layer and the insulator and widen the bandwidth of the detecting signal.

Abstract: A conduction control device comprises a first ferromagnetic region having relatively high coercivity, a second ferromagnetic region having relatively low coercivity and a junction region disposed between the first and second ferromagnetic regions. The device also comprises a gate for applying a field to the junction region so as to control charge carrier density within the junction region.

Abstract: A magnetic recording medium, a hard disk using the same, and a manufacturing method thereof are provided. In one example, the magnetic nano-particle medium is formed by depositing a magnetic nano-particle colloid on a substrate, wherein the axes of easy magnetization of respective crystalline particles are aligned with high accuracy. A layer of L10 alloy nano-particles which will exhibit magnetic properties through an order-disorder transition, and arranged at a substantially uniform spacing on a substrate, and a carbon-containing covering film for surrounding these nano-particles and making the spacing substantially uniform are provided. To the L10 alloy of the nano-particles, at least one non-magnetic element is added, or a covered layer comprising at least one non-magnetic layer is formed therearound.

Abstract: An information storage device having a hard disk has a metal probe that is brought closely to the surface of a multilayer film that includes a magnetic metal layer, a non-magnetic metal layer, and a magnetic metal layer up to a nano-meter order distance from the surface. The distance between the metal probe and the surface of the multilayer film, as well as the voltage to be applied are changed to change the state of the quantum well generated in the multilayer film, thereby changing the magnetizing direction relatively between the two magnetic metal layers. To read magnetization information from the hard disk, a change of an optically induced tunnel current is used. The change of the tunnel current is caused by a change of a plasmon resonance energy according to a relative change of the magnetizing direction between the magnetic metal layers.

Abstract: The invention provides a magnetic head for perpendicular recording capable of recording with high linear recording density and high track density, and a magnetic disk drive incorporating the same. In order to achieve this, one or more sides of the main pole of the magnetic head for perpendicular recording except for the trailing side are formed in a taper with an appropriate angle against the tip surface of the main pole, and the yoke whose widest principal plane is in parallel to the tip surface is provided on the bottom of the main pole. Thereby, the invention achieves the magnetic head for perpendicular recording that generates a sufficiently high magnetic field, and assumes a sharp gradient of magnetic field on the trailing side. By incorporating this magnetic head, a magnetic disk drive capable of handling high linear recording density can be produced.

Abstract: A memory cell in a so-called MRAM by utilizing a tunnel magnetic resistance in the prior art has raised problems that a magnetic field to be applied to a TMR element is essentially weak since a word line for write is disposed apart from the TMR element, that a large current is required at the time of a writing operation, and that electric power consumption is large. In order to solve the above-described problems experienced in the prior art, the present invention provides an MRAM memory cell structure and its fabricating method in which a word line for write is disposed near a TMR element and surrounds it in three directions.

Abstract: For providing a recording/reproducing apparatus, for recording/reproducing information through conduction of electricity upon contact of a probe, having large recording density and a large transfer speed, but less in deterioration of a probe chips thereof, and being long in the lifetime thereof, within the recording/reproducing apparatus, a multi-chip is formed, disposing probe chips in large numbers thereof at a tip of a cantilever, while the cantilever is of a double-sided beam type, and the multi-chip is disposed at a center of the beam, wherein recording/reproducing portions of the multi-chip are disposed to correspond to recording dots one by one, and the multi-chip forming surface is moved up and down in parallel with the surface of a recording medium, due to suction force, so as to bring it to be in contact with the recording dots, and electricity is conducted after the contact thereof, thereby conducting the recording, in the structure; wherein, since a large amount of data can be read/written at one

Abstract: Disclosed is a magnetic memory apparatus which comprises a patterned magnetic recording medium in which multilayered films each having a first magnetic layer, a nonmagnetic metal layer or a nonmagnetic insulating layer and a second magnetic layer deposited discretely on a conductive electrode layer formed on a substrate, and a cantilever array having a plurality of cantilevers each having a conductive chip at its distal end. This provides a magnetic solid memory apparatus that has a large memory capacity and a super fast transfer rate, the merits of a hard disk apparatus, and a nanostructure and low power consumption, which are the merits of a semiconductor memory.

Abstract: A three terminal magnetoresistance head capable of providing a high output and a large output current is provided. A MIS junction multilayer film composed of a magnetic semiconductor, a metal magnetic multilayer film, and a tunnel magnetoresistance element is applied to a three terminal magnetoresistance device.

Abstract: A perpendicular magnetic recording medium for thermo-magnetic printing has an ultra-high recording density and is resistant to thermal decay of magnetization. An intermediate layer of the medium is provided between a first recording layer using a low-noise Co alloy ferromagnetic substance and a second recording layer using a ferrimagnetic substance (e.g., a rare-earth element-transition metal compound) having a compensation temperature below an operation ambient temperature. A magnetic field is applied thereto to form a magnetization pattern on the first recording layer. It is then heated-up to be printed onto the second recording layer, which has a higher coercivity at the ambient temperature, and a recording field is suitably set to form a magnetization pattern only on the first recording layer. The magnetization pattern is printed from the first recording layer to the second recording layer.

Abstract: A TMR head capable of reconciling high output with high band width is implemented. To that end, two multilayered films each comprised of an insulating layer and a ferromagnetic layer are formed at different locations on an electrode layer, and a current is caused to flow from the ferromagnetic layer of a first multilayered film to the electrode layer while polarized spin is diffused up to a portion of the electrode layer, directly underneath the other multilayered film comprised of the insulating layer and the ferromagnetic layer, thereby detecting a change in resistance, according to a change in the magnetization direction of the ferromagnetic layer of a second multilayered film by use of a circuit extremely large in input impedance, such as a FET.