An oscillator includes a spin current source, and a free layer coupled to the spin current source. The free layer has a magnetization hard axis that is parallel to a quantization axis of a spin current injected by the spin Hall effect of the spin current source.

A variable-frequency magnetoresistive effect element includes a magnetoresistive effect element, a magnetic-field applying mechanism that applies a magnetic field to the magnetoresistive effect element, an electric-field applying mechanism that applies an electric field to the magnetoresistive effect element, and a control terminal connected to the electric-field applying mechanism and used for applying a voltage that varies in at least one of magnitude and polarity to the electric-field applying mechanism. The magnetoresistive effect element contains an antiferromagnetic material or ferrimagnetic material having a magnetoelectric effect. A spin torque oscillation frequency or spin torque resonance frequency of the magnetoresistive effect element is controlled by varying the voltage applied via the control terminal in at least one of magnitude and polarity.

A magnetoresistance effect device includes a first port, a second port, a first circuit unit and a second circuit unit which are connected in series between the first port and the second port, a shared reference electric potential terminal or a first reference electric potential terminal and a second reference electric potential terminal, and a shared DC application terminal or a first DC application terminal and a second DC application terminal, wherein the first circuit unit and the second circuit unit include a magnetoresistance effect element and a conductor connected to one end thereof, a first end portion of the conductor is connected to a high-frequency current input side, and a second end portion of the first conductor is connected to the shared reference electric potential terminal, the first reference electric potential terminal or the second reference electric potential terminal.

The magnetoresistance effect device includes first and second ports, a first circuit unit and a second circuit unit connected between the first port and the second port, a shared reference electric potential terminal or a first reference electric potential terminal and a second reference electric potential terminal, and a shared DC application terminal or a first DC application terminal and a second DC application terminal, the first circuit unit includes a first magnetoresistance effect element, the second circuit unit includes a second magnetoresistance effect element and a first conductor separated from the second magnetoresistance effect element with an insulating body therebetween and a first end portion of the first conductor is connected to an input side of high frequency current such that high frequency magnetic field generated by the high frequency current flowing through the first conductor is applied to the magnetization free layer of the second magnetoresistance effect element.

The disclosed technology provides various implementations of a device based on a spin Hall effect (SHE) and spin transfer torque (STT) effect. In one aspect, a device is provided to include a magnetic structure including a ferromagnetic layer having a magnetization direction that can be changed by spin transfer torque; a SHE layer that is electrically conducting and exhibits a spin Hall effect to, in response to an applied charge current, generate a spin-polarized current that is perpendicular to the applied charge current, the SHE layer located adjacent to the ferromagnetic layer to inject the spin-polarized current into the ferromagnetic layer; a first electrical contact in contact with the magnetic structure; a second electrical contact in contact with a first location of the SHE layer; a third electrical contact in contact with a second location of the SHE layer so that the first and second locations are on two opposite sides of the magnetic structure; a magnetic structure circuit coupled between the first electrical contact and one of the second and third electrical contacts to supply a current or a voltage to the magnetic structure; and a charge current circuit coupled between the second and third electrical contacts to supply the charge current into the SHE layer, wherein the device is operable at a low write error rate with pulses of a pulse duration of around 2 ns or shorter to switch a direction of the magnetization direction of the ferromagnetic layer in the magnetic structure.

At least one magnetoresistance effect element and a magnetic field applying unit to apply a magnetic field to the magnetoresistance effect element, the magnetic field applying unit includes a first ferromagnetic material having a portion protruding to the magnetoresistance effect element side in a stacking direction of the magnetoresistance effect element, a second ferromagnetic material sandwiching the magnetoresistance effect element with the first ferromagnetic material, and a coil wound around the first ferromagnetic material, a first magnetization free layer of the magnetoresistance effect element has a portion free of overlapping with at least one of a second surface of the protruding portion on the magnetoresistance effect element side and a third surface of the second ferromagnetic material on the magnetoresistance effect when viewed in the stacking direction, and a center of gravity of the first magnetization free layer, positioned in a region connecting the second surface and the third surface.

Described is an oscillating apparatus which comprises: an interconnect with spin-coupling material (e.g., Spin Hall Effect (SHE) material); and a magnetic stack having two magnetic layers such that one of the magnetic layers is coupled to the interconnect, wherein each of the two magnetic layers have respective magnetization directions to cause the magnetic stack to oscillate.

An array of magnetic nanoparticle (MNP) spin torque oscillators (STOs) is described. Each STO is comprised of a uniform, chemically synthesized, spherical nanoparticle which couples to current flowing along a surface. The particles are organized into an array by a self-assembly technique with uniform spacing and close proximity to allow strong electrical and magnetic coupling between particles. The coupling of the nanoparticles to the surface current drives the oscillations by spin-torque, and for phase locking and data input. The uniform, spherical shape of the particles allows the oscillations to be achieved at low currents and with low power dissipation. The MNP-STOs may be used as a basis for massively parallel computing, microwave oscillators, or other applications.

A memory device includes a plurality of layers forming a stack. The plurality of layers include a spin polarization layer having a magnetic anisotropy approximately perpendicular to a plane of the spin polarization layer, an antiferromagnetic layer having an antiferromagnetic material, a ferromagnetic layer that is exchange coupled to the antiferromagnetic layer, where the antiferromagnetic layer is between the ferromagnetic layer and the spin polarization layer, and a storage layer having a magnetization direction that indicates a memory state of the storage layer. The memory state is switched by an amount of current through the stack. The spin polarization layer, the ferromagnetic layer, and the antiferromagnetic layer are configured to reduce the amount of current through the stack for switching the magnetization direction of the storage layer relative to an amount of current through a memory device without the spin polarization layer, the ferromagnetic layer, and the antiferromagnetic layer.

A magnetoresistance effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, wherein at least one of the first ferromagnetic layer and the second ferromagnetic layer includes a first layer and a second layer in order from the side closer to the non-magnetic layer, the first layer contains a crystallized Co-based Heusler alloy, at least a part of the second layer is crystallized, the second layer contains a ferromagnetic element, boron element and an additive element, and the additive element is any element selected from a group consisting of Ti, V, Cr, Cu, Zn, Zr, Mo, Ru, Pd, Ta, W, Ir, Pt, and Au.