Embodiments may provide the realization of strong Dzyaloshinskii-Moriya Interaction (DMI) and perpendicular magnetic anisotropy (PMA) induced by chemisorbed species on a ferromagnetic layer. For example, in an embodiment, an apparatus for generating a Dzyaloshinskii-Moriya interaction may comprise a ferromagnet comprising a single layer or multi-layers of materials made of metal, oxide or other types of magnetic films, and a substance chemisorbed on a surface of the ferromagnet to induce the Dzyaloshinskii-Moriya interaction or the perpendicular magnetic anisotropy at the interface between chemisorbed species and ferromagnet. These induced effects may be used to manipulate spin textures such as switching of domain wall chirality and writing/deleting of magnetic skyrmions, which are relevant for spintronics, magneto-ionics as well as gas sensing.

A magnetoresistive effect element includes a magnetization fixed layer, a magnetization free layer, and a non-magnetic spacer layer that is stacked between the magnetization fixed layer and the magnetization free layer. The magnetization free layer includes a first free layer and a second free layer that are formed of a ferromagnetic material, and a magnetic coupling layer that is stacked between the first free layer and the second free layer. The first free layer and the second free layer are magnetically coupled to each other by exchange coupling via the magnetic coupling layer such that magnetization directions of the first free layer and the second free layer are antiparallel to each other. The magnetic coupling layer is a non-magnetic layer that includes Ir and at least one of the following elements: Fe, Co and Ni.

A neuro-stimulation system includes a stimulator controller, a support surface, and a magneto-ionic stimulator positioned on the support surface and electrically connected to the stimulator controller. The stimulator controller can apply a voltage to the magneto-ionic stimulator, wherein a change in the voltage causes a change in a magnetic field produced by the magneto-ionic stimulator.

A magnetoresistance effect element of the present invention includes: a barrier layer; a reference layer formed on one surface of the barrier layer; a free layer formed on the other surface of the barrier layer; and a pinned layer placed on the opposite side of the reference layer from the barrier layer. The pinned layer includes a structure obtained by stacking Ni, Co, Pt, Co, Ru, Co, Pt, Co, and Ni layers in this order.

An in-plane magnetized film for use as a hard bias layer of a magnetoresistive effect element contains metal Co, metal Pt, and an oxide and has a thickness of 20 nm or more and 80 nm or less, wherein: the in-plane magnetized film contains the metal Co in an amount of 45 at% or more and 80 at% or less and the metal Pt in an amount of 20 at% or more and 55 at% or less relative to a total of metal components of the in-plane magnetized film; the in-plane magnetized film contains the oxide in an amount of 3 vol% or more and 25 vol% or less relative to a whole amount of the in-plane magnetized film; and the in-plane direction average grain diameter of magnetic crystal grains of the in-plane magnetized film is 15 nm or more and 30 nm or less.

The invention comprises a novel composite seed structure (CSS) having lattice constant matched crystalline structure with the Co layer in above perpendicular magnetic pinning layer (pMPL) so that an excellent epitaxial growth of magnetic super lattice pinning layer [Co/(Pt, Pd or Ni)].sub.n along its FCC (111) orientation can be achieved, resulting in a significant enhancement of perpendicular magnetic anisotropy (PMA) for perpendicular spin-transfer-torque magnetic-random-access memory (pSTT-MRAM) using perpendicular magnetoresistive elements as basic memory cells which potentially replace the conventional semiconductor memory used in electronic chips, especially mobile chips for power saving and non-volatility.

In one embodiment, a desirable (e.g., substantially 100%) SOT switching probability is achieved in a SOT device by applying in-plane input current as one or more pulses having a tuned pulse width. In the case of a single pulse, pulse width may be selected as a single tuned pulse width or a range of pulse widths that avoid a specific pulse width determined to cause a switch-back response. In the case of multiple pulses, pulse width, a time interval between pulses and other factors such as intensities may be selected to prevent a switch-back response. Further, SOT switching speed may be achieved by reducing incubation delay through modification of an external magnetic field or input current density applied to the SOT device.

Provided is a method of measuring a magnitude of magnetization of a perpendicular magnetic thin film, including: forming a stripe pattern in which a first magnetic domain that extends in a y direction and is magnetized in a z direction and a second magnetic domain that extends in the y direction and is magnetized in a direction opposite to the z direction are arranged alternately in an x direction, in a perpendicular magnetic thin film that extends in an xy plane; changing widths in the x direction, of the first and second magnetic domains by applying a magnetic field having a predetermined magnitude, in the z direction, to the perpendicular magnetic thin film; and calculating an absolute value of the magnetization of the perpendicular magnetic thin film on the basis of a ratio between the widths in the x direction, of the first magnetic domain and the second magnetic domain.

A method for inducing tunable ferromagnetism with hydrogen annealing in delafossite films includes obtaining a PdCoO.sub.2 thin film, positioning the PdCoO2 thin film on a substrate, annealing the PdCoO.sub.2 thin film by hydrogenation, and cooling the PdCoO.sub.2 thin film to approximately room temperature.

Embodiments may provide a realization of strong Dzyaloshinskii-Moriya interaction (DMI) and perpendicular magnetic anisotropy (PMA) induced by chemisorbed species on a ferromagnetic layer. For example, in an embodiment, an apparatus for generating DMI may comprise a ferromagnet comprising a single-layer or multi-layers of materials made of metal, oxide or other types of magnetic films, and a substance chemisorbed on a surface of the ferromagnet to induce the DMI or the PMA at the interface between the chemisorbed species and the ferromagnet. These induced effects may be used to maniupulate spin textures such as switching of domain wall chirality and writing/deleting of magnetic skyrmions, which are relevant for spintronics and magneto-ionics as well as for gas sensing.