Abstract: A method and apparatus for stray magnetic field compensation in a non-volatile memory cell, such as a spin-torque transfer random access memory (STRAM). In some embodiments, a first tunneling barrier is coupled to a reference structure that has a perpendicular anisotropy and a first magnetization direction. A recording structure that has a perpendicular anisotropy is coupled to the first tunneling barrier and a nonmagnetic spacer layer. A compensation layer that has a perpendicular anisotropy and a second magnetization direction in substantial opposition to the first magnetization direction is coupled to the nonmagnetic spacer layer. Further, the memory cell is programmable to a selected resistance state with application of a current to the recording structure.

Abstract: A bit patterned media (BPM) includes many magnetic dots arranged in tracks on a substrate. The magnetic dots each have a hard magnetic core, a soft magnetic cladding surrounding the core and a thin non-magnetic layer that separates the hard magnetic core from the soft magnetic ring. The soft magnetic cladding stabilizes the magnetization at the edges of the hard magnetic core to improve the signal to noise ratio of the magnetic dots. The soft magnetic rings also narrow the magnetic field of the dots which reduces the space requirements and allows more dots to be placed on the substrate.

Abstract: Write verify methods for resistance random access memory (RRAM) are provided. The methods include applying a reset operation voltage pulse across a RRAM cell to change a resistance of the RRAM cell from a low resistance state to a high resistance state and applying a forward resetting voltage pulse across the RRAM cell if the RRAM cell has a high resistance state resistance value less than a selected lower resistance limit value. The method also includes applying a reverse resetting voltage pulse across the RRAM cell if the RRAM cell has a high resistance state resistance values is greater than a selected upper resistance limit value. The reverse resetting voltage pulse has a second polarity being opposite the first polarity.

Abstract: Spin-transfer torque memory includes a composite free magnetic element, a reference magnetic element having a magnetization orientation that is pinned in a reference direction, and an electrically insulating and non-magnetic tunneling barrier layer separating the composite free magnetic element from the magnetic reference element. The free magnetic element includes a hard magnetic layer exchanged coupled to a soft magnetic layer. The composite free magnetic element has a magnetization orientation that can change direction due to spin-torque transfer when a write current passes through the spin-transfer torque memory unit.

Abstract: An apparatus and method for compensating for asymmetric write current in a non-volatile unit cell. The unit cell comprises a switching device and an asymmetric resistive sense element (RSE), such as an asymmetric resistive random access memory (RRAM) element or an asymmetric spin-torque transfer random access memory (STRAM) element. The RSE is physically oriented within the unit cell relative to the switching device such that a hard direction for programming the RSE is aligned with an easy direction of programming the unit cell, and an easy direction for programming the RSE is aligned with a hard direction for programming the unit cell.

Abstract: Magnetic shift registers in which data writing and reading is accomplished by moving the magnetic domain walls by electric current. Various embodiments of domain wall nodes or anchors that stabilize a domain wall are provided. In some embodiments, the wall anchors are elements separate from the magnetic track. In other embodiments, the wall anchors are disturbances in the physical configuration of the magnetic track. In still other embodiments, the wall anchors are disturbances in the material of the magnetic track.

Abstract: A magnetic memory device includes a magnetic tunnel junction having a free magnetic layer having a magnetization orientation that is switchable between a high resistance state magnetization orientation and a low resistance state magnetization orientation and a memristor solid state element electrically coupled to the magnetic tunnel junction. The memristor has a device response that is an integrated voltage versus an integrated current.

Abstract: A method and apparatus for stray magnetic field compensation in a non-volatile memory cell, such as a spin-torque transfer random access memory (STRAM). In some embodiments, a first tunneling barrier is coupled to a reference structure that has a perpendicular anisotropy and a first magnetization direction. A recording structure that has a perpendicular anisotropy is coupled to the first tunneling barrier and a nonmagnetic spacer layer. A compensation layer that has a perpendicular anisotropy and a second magnetization direction in substantial opposition to the first magnetization direction is coupled to the nonmagnetic spacer layer. Further, the memory cell is programmable to a selected resistance state with application of a current to the recording structure.

Abstract: A programmable metallization memory cell that has an apertured insulating layer comprising at least one aperture therethrough positioned between the active electrode and the inert electrode. Superionic clusters are present within the at least one aperture, and may extend past the at least one aperture. Also, methods for making a programmable metallization memory cell are disclosed.

Abstract: A magnetic memory unit includes a tunneling barrier separating a free magnetic element and a reference magnetic element. A first phonon glass electron crystal layer is disposed on a side opposing the tunneling barrier of either the free magnetic element or the reference magnetic element. A second phonon glass electron crystal layer also be disposed on a side opposing the tunneling barrier of either the free magnetic element or the reference magnetic element to provide a Peltier effect on the free magnetic element and the reference magnetic element.

Abstract: Electronic devices that include (i) a magnetization controlling structure; (ii) a tunnel barrier structure; and (iii) a magnetization controllable structure including: a first polarizing layer; and a first stabilizing layer, wherein the tunnel barrier structure is between the magnetization controlling structure and the magnetization controlling structure and the first polarizing layer is between the first stabilizing layer and the tunnel barrier structure, wherein the electronic device has two stable overall magnetic configurations, and wherein a first unipolar current applied to the electronic device will cause the orientation of the magnetization controlling structure to reverse its orientation and a second unipolar current applied to the electronic device will cause the magnetization controllable structure to switch its magnetization in order to obtain one of the two stable overall magnetic configurations, wherein the second unipolar current has an amplitude that is less than the first unipolar current.

Abstract: Electronic devices that include (i) a magnetization controlling structure; (ii) a tunnel barrier structure; and (iii) a magnetization controllable structure including: a first polarizing layer; and a first stabilizing layer, wherein the tunnel barrier structure is between the magnetization controlling structure and the magnetization controlling structure and the first polarizing layer is between the first stabilizing layer and the tunnel barrier structure, wherein the electronic device has two stable overall magnetic configurations, and wherein a first unipolar current applied to the electronic device will cause the orientation of the magnetization controlling structure to reverse its orientation and a second unipolar current applied to the electronic device will cause the magnetization controllable structure to switch its magnetization in order to obtain one of the two stable overall magnetic configurations, wherein the second unipolar current has an amplitude that is less than the first unipolar current.

Abstract: A spin-torque probe microscope and methods of using the same are described. The spin-torque probe microscope includes a cantilever probe body, a magnetic tip disposed at a distal end of the cantilever probe body, an electrically conductive sample disposed proximate to the magnetic tip, an electrical circuit providing a spin-polarized electron current to the electrically conductive sample, and a vibration detection element configured to sense vibration frequency of the cantilever probe body. The spin-polarized electron current is sufficient to alter a local electron spin or magnetic moment within the electrically conductive sample and be sensed by the magnetic tip.

Abstract: A magnetic memory device includes a magnetic tunnel junction having a free magnetic layer having a magnetization orientation that is switchable between a high resistance state magnetization orientation and a low resistance state magnetization orientation and a memristor solid state element electrically coupled to the magnetic tunnel junction. The memristor has a device response that is an integrated voltage versus an integrated current.

Abstract: Write verify methods for resistance random access memory (RRAM) are provided. The methods include applying a reset operation voltage pulse across a RRAM cell to change a resistance of the RRAM cell from a low resistance state to a high resistance state. Then the method includes applying a forward resetting voltage pulse across the RRAM cell if the RRAM cell has a high resistance state resistance value less than a selected lower resistance limit value. This step is repeated until the high resistance state resistance value is greater than the lower resistance limit value. The method also includes applying a reverse resetting voltage pulse across the RRAM cell if the RRAM cell has a high resistance state resistance values is greater than a selected upper resistance limit value. The reverse resetting voltage pulse has a second polarity being opposite the first polarity. This step is repeated until all the high resistance state resistance value is less than the upper resistance limit value.

Abstract: Variable write and read methods for resistance random access memory (RRAM) are disclosed. The methods include initializing a write sequence and verifying the resistance state of the RRAM cell. If a write pulse is needed, then two or more write pulses are applied through the RRAM cell to write the desired data state to the RRAM cell. Each subsequent write pulse has substantially the same or greater write pulse duration. Subsequent write pulses are applied to the RRAM cell until the RRAM cell is in the desired data state or until a predetermined number of write pulses have been applied to the RRAM cell. A read method is also disclosed where subsequent read pulses are applied through the RRAM cell until the read is successful or until a predetermined number of read pulses have been applied to the RRAM cell.

Abstract: A method and apparatus for repairing a stuck-at defect condition in a non-volatile memory cell, such as a spin-torque transfer random access memory (STRAM). In some embodiments, a resistive sense element has a magnetic tunneling junction (MTJ) and a repair plane located adjacent to the resistive sense element. The repair plane injects a magnetic field in the MTJ to repair a stuck-at defect condition.

Abstract: Spin-transfer torque memory having a compensation element is disclosed. A spin-transfer torque memory unit includes a free magnetic layer having a magnetic easy axis and a magnetization orientation that can change direction due to spin-torque transfer when a write current passes through the spin-transfer torque memory unit; a reference magnetic element having a magnetization orientation that is pinned in a reference direction; an electrically insulating and non-magnetic tunneling barrier layer separating the free magnetic layer from the magnetic reference element; and a compensation element adjacent to the free magnetic layer. The compensation element applies a bias field on the magnetization orientation of the free magnetic layer. The bias field is formed of a first vector component parallel to the easy axis of the free magnetic layer and a second vector component orthogonal to the easy axis of the free magnetic layer.

Abstract: A biosensor is described. The biosensor includes a fixed multilayer stack providing a magnetization oscillation, a voltage source electrically coupled to the fixed multilayer stack, and a binding molecule covalently bonded to the biosensor. The voltage source provides a direct current through the fixed multilayer stack to generate the magnetization oscillation and a target molecule including a magnetic nanoparticle forms a complex with the binding molecule and alters the magnetization oscillation.

Abstract: A magnetic cell includes a ferromagnetic free layer having a free magnetization orientation direction and a first ferromagnetic pinned reference layer having a first reference magnetization orientation direction that is parallel or anti-parallel to the free magnetization orientation direction. A first oxide barrier layer is between the ferromagnetic free layer and the first ferromagnetic pinned reference layer. The magnetic cell further includes a second ferromagnetic pinned reference layer having a second reference magnetization orientation direction that is orthogonal to the first reference magnetization orientation direction. The ferromagnetic free layer is between the first ferromagnetic pinned reference layer and the second ferromagnetic pinned reference layer.