A magnetic element is formed from a magnetic material, which is a material that is capable of generating a magnetic skyrmion, and a defect is introduced at a position corresponding to each side of an approximate triangle in plan view. A magnetic field having such a direction and an intensity as to generate at least one magnetic skyrmion in an area corresponding to inside of the approximate triangle is applied to the magnetic material with the defects introduced therein. This causes the magnetic skyrmion to be generated in the area corresponding to inside of the approximate triangle. This configuration enables the generated magnetic skyrmion to be stably kept at a higher temperature.

A method for producing a tunnel magnetoresistive element includes a stacking step, then in-magnetic field heating, and then dry etching. The stacking includes stacking a B absorption layer which is in contact with an upper surface of a CoFeB layer. The dry etching includes removal of layers to the B absorption layer. An end of etching is set as an end point time detected by an analysis device when a final layer before the B absorption layer directly above the CoFeB layer is exposed has reduced to a prescribed level, or when the B absorption layer directly above the CoFeB layer has increased to the prescribed level. An amount of over-etching after the end point time is specified in advance, and the B absorption layer is stacked such that the thickness from the prescribed level to the upper surface of the CoFeB layer corresponds to the over-etching amount.

According to one embodiment, an electromagnetic wave attenuator includes a plurality of magnetic layers, and a plurality of nonmagnetic layers. The plurality of nonmagnetic layers is conductive. A direction from one of the plurality of magnetic layers toward an other one of the plurality of magnetic layers is aligned with a first direction. One of the plurality of nonmagnetic layers is between the one of the plurality of magnetic layers and the other one of the plurality of magnetic layers. A first thickness along the first direction of the one of the plurality of magnetic layers is not less than times a second thickness along the first direction of the one of the plurality of nonmagnetic layers.

According to one embodiment, an electromagnetic wave attenuator includes a plurality of magnetic layers, and a plurality of nonmagnetic layers. The plurality of nonmagnetic layers is conductive. A direction from one of the plurality of magnetic layers toward an other one of the plurality of magnetic layers is aligned with a first direction. One of the plurality of nonmagnetic layers is between the one of the plurality of magnetic layers and the other one of the plurality of magnetic layers. A first thickness along the first direction of the one of the plurality of magnetic layers is not less than times a second thickness along the first direction of the one of the plurality of nonmagnetic layers.

A magnetic material includes a structure in which a first magnetic layer 1 and a second magnetic layer 2 are stacked such that each layer is formed at least partially in a stacking direction by substantially one atomic layer. The first magnetic layer contains Co as a principal component. The second magnetic layer includes at least Ni. The magnetic material has magnetic anisotropy in the stacking direction. Preferably, an atomic arrangement within a film surface of the first magnetic layer and the second magnetic layer has six-fold symmetry.

A magnetic detection circuit for a magnetic random access memory (MRAM) is provided. The magnetic detection circuit includes a sensing array including a plurality of sensing cells and a controller. Each of the sensing cells includes a first magnetic tunnel junction (MTJ) device. The controller is configured to access the first MRAM cells to detect the external magnetic field strength of the MRAM. The controller determines whether to stop the write operation of a plurality of memory cells of the MRAM according to the external magnetic field strength of the MRAM, and each of the memory cells includes a second MTJ device. The first MTJ device is smaller than the second MTJ device.

A magnetic detection circuit for a magnetic random access memory (MRAM) is provided. The magnetic detection circuit includes a sensing array including a plurality of sensing cells and a controller. Each of the sensing cells includes a first magnetic tunnel junction (MTJ) device. The controller is configured to access the first MRAM cells to detect the external magnetic field strength of the MRAM. The controller determines whether to stop the write operation of a plurality of memory cells of the MRAM according to the external magnetic field strength of the MRAM, and each of the memory cells includes a second MTJ device. The first MTJ device is smaller than the second MTJ device.

A magnetoresistance effect element has a first ferromagnetic metal layer, a second ferromagnetic metal layer, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, the tunnel barrier layer is expressed by a composition formula of AB.sub.2O.sub.x (0<x4), and has a spinel structure in which cations are arranged in a disordered manner, the tunnel barrier layer has a lattice-matched portion and a lattice-mismatched portion, A is a divalent cation of plural non-magnetic elements, B is an aluminum ion, and in the composition formula, the number of the divalent cation is smaller than half the number of the aluminum ion.

A magnetoresistance effect element has a first ferromagnetic metal layer, a second ferromagnetic metal layer, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, the tunnel barrier layer is expressed by a composition formula of AB.sub.2O.sub.x (0<x4), and has a spinel structure in which cations are arranged in a disordered manner, the tunnel barrier layer has a lattice-matched portion and a lattice-mismatched portion, A is a divalent cation of plural non-magnetic elements, B is an aluminum ion, and in the composition formula, the number of the divalent cation is smaller than half the number of the aluminum ion.

A laminated seed layer stack with a smooth top surface having a peak to peak roughness of 0.5 nm is formed by sequentially sputter depositing a first seed layer, a first amorphous layer, a second seed layer, and a second amorphous layer where each seed layer may be Mg and has a resputtering rate 2 to 30X that of the amorphous layers that are TaN, SiN, or a CoFeM alloy. A template layer that is NiCr or NiFeCr is formed on the second amorphous layer. As a result, perpendicular magnetic anisotropy in an overlying magnetic layer that is a reference layer, free layer, or dipole layer is substantially maintained during high temperature processing up to 400 C. and is advantageous for magnetic tunnel junctions in embedded MRAMs, spintronic devices, or in read head sensors. The laminated seed layer stack may include a bottommost Ta or TaN buffer layer.