22 results about "Antiferromagnetism" patented technology

A bilayer film of a magnetic body and an insulator has an antiferromagnetic layer having a hexagonal crystal structure and at least one surface of which is the (10-10) surface of an antiferromagnetic body, and an insulator layer containing two or three or four atoms laminated on the (10-10) surface of the antiferromagnetic layer. A bilayer film of a magnetic body and an insulator has an antiferromagnetic layer having a hexagonal crystal structure and at least one surface of which is the (0001) surface of an antiferromagnetic body, and an insulator layer containing two or three or four atoms laminated on the (0001) surface of the antiferromagnetic layer. The tunneling magnetoresistive element has a second antiferromagnetic film layer laminated on the insulator of the bilayer film. The magnetic memory includes a plurality of the tunneling magnetoresistive elements.

In order to reduce the amount of rare earth metals such as Ho or Er in a cold storage material for a cryogenic refrigerator, the cold storage material (15) for a cryogenic refrigerator contains crystals of CuFe1-xMxO2 (M is a metal element other than Fe), and in a temperature range of 10 K or less, CuFe1-xMxO2 exhibits antiferromagnetic properties and has a volumetric specific heat greater than that of lead.

To provide a thin thermoelectric conversion element having flexibility.SOLUTION: A thermoelectric transducer comprising: a substrate having flexibility; a base layer formed on the substrate and made of a metal-oxide material; and a magnetic layer laminated on the base layer and having conductivity and ferromagnetic or antiferromagnetic properties, wherein a thickness of the base layer is not less than 10nm and not more than 50nm.SELECTED DRAWING: Figure 1

To provide a quantum converter and a quantum conversion method capable of improving conversion efficiency even when light with low loss in an optical fiber is used.SOLUTION: The quantum transducer includes a three dimensional cavity resonator, and a nonmagnetic first insulator film and a ferromagnetic or antiferromagnetic second insulator film that are provided in the three dimensional cavity resonator and are stacked on each other, A laminate including an interface between the first insulator film and the second insulator film, a magnetic field application unit configured to apply a magnetic field including a component perpendicular to the interface to the laminate, and a microwave transmission and reception unit configured to transmit and receive microwaves to and from the laminate, wherein the first insulator film and the second insulator film do not include a topological insulator, the second insulator film has an easy magnetization axis along a first axis perpendicular to the interface, and the laminate is irradiated with laser light from a direction inclined with respect to the first axis. Quantum converters can be used, for example, in quantum computing.SELECTED DRAWING: Figure 1

The application discloses a multi-state memory unit based on anti-ferromagnetic, and relates to the technical field of spintronic devices, and aims to solve the problems that multi-bit storage of a single device cannot be realized and data writing is difficult in the prior art.The application comprises a magnetic tunnel junction, a bottom electrode layer serving as a current writing line, the magnetic tunnel junction is used for storing data, and the bottom electrode layer is used for providing spin-orbit torque to write data; the magnetic tunnel junction at least comprises a fixed layer, a barrier layer and a free layer; the free layer is adjacent to an anti-ferromagnetic layer, and exchange bias is formed between the anti-ferromagnetic layer and the free layer; a current is applied on the corresponding bottom electrode to reverse the direction of the free layer and the exchange bias to a direction perpendicular to the current; and the free layer and the exchange bias are controlled to reverse the angle by applying the current in the current writing line at different angles, so that more intermediate states can be obtained in the whole magnetic resistance range. Not only can the application realize magnetic field-free writing of data, but also can realize extremely stable multi-bit storage.

The invention belongs to the technical field of multiferroic materials, and relates to a design method of a multiferroic body based on a vanadium-doped two-dimensional ferroelectric and the multiferroic body. Performing cell expansion on the single-layer NbOI2 primitive cell in different directions to obtain supercells with different sizes; the method comprises the following steps: doping supercells with different sizes by taking vanadium as a doping element to obtain a doping configuration of each supercell under different doping concentrations; taking the doping configuration with the lowest total energy of the ferromagnetic state and the antiferromagnetic state under each doping concentration as the ground state configuration of the doping concentration; calculating band gaps Eg of ground state configurations with different doping concentrations and spontaneous ferroelectric polarization intensity along a b axis, drawing a double-Y-axis curve graph by taking the doping concentrations as abscissas and the spontaneous ferroelectric polarization intensity and the band gaps Eg as ordinates, and dividing a multiferroic phase region and a magnetic semimetal phase region to obtain a doping concentration-physical property evolution phase diagram; and obtaining a corresponding doping concentration value range when the ground state configuration has a multiferroic phase with ferroelectricity and antiferromagnetism so as to design a multiferroic body.

The antiferromagnetic material has a hexagonal crystal structure and has an antiferromagnetic layer containing Mn3A1-xBx (0lt, xlt, 0.5, A = Ga, Ge, Sn, B = Mg, Al, Si, P, Mn, Ni, Cu, Zn, As, Ru, Ag, Cd, In, Sb, Os, Au, Hg, T1, Pb) or (Mn1-pCrp) 3GaqGerSn1-q-r (0lt, plt, 0.5, 0lt, qlt, 1, 0lt, rlt, 1, 0lt, q + r < = 1), and an insulator layer laminated on the surface of the antiferromagnetic layer. It is preferable that A is Ga and / or Sn. In addition, it is preferable that B is at least one of Mg, Al, Si, Mn, Cu, Zn, Ag, Cd, In, Sb, Au, and Tl.

The invention relates to a face-centered cubic antiferromagnetic gamma-CoMn alloy single crystal film and a preparation method thereof, and belongs to the technical field of condensed state physical materials. The face-centered cubic antiferromagnetic gamma-CoMn alloy single crystal film comprises a substrate, a buffer layer and a gamma-CoMn alloy single crystal film which are sequentially arranged from bottom to top, the chemical composition of the gamma-CoMn alloy single crystal film is gamma-Co1-xMnx, wherein x is greater than or equal to 50 and less than or equal to 70. The invention further provides a preparation method of the antiferromagnetic gamma-CoMn alloy single crystal thin film. The antiferromagnetic gamma-CoMn alloy single crystal thin film is of a face-centered cubic phase, the epitaxial relationship between the gamma-CoMn alloy single crystal thin film and a substrate is CoMn (111) [10] Si (111) [11] and CoMn (111) [10] Si (111) [11] coexisting twin crystal growth, and the antiferromagnetic gamma-CoMn alloy single crystal thin film has atomic-level surface flatness, good single crystal epitaxial orientation and antiferromagnetism, is suitable for subsequent scientific research, and has good application prospects. The material is an excellent material applied to antiferromagnetic electronic devices.

The invention provides an anisotropic conductive film and a conductive connector which can realize low resistance, improvement of high-frequency characteristics, high resolution, improvement of contact stability caused by reduction of contact pressure, high current and improvement of durability compared with the prior art. The anisotropic conductive film (110) is provided with: an insulating film (112) comprising an elastic polymer material; and particles (200) which are dispersed in the insulating film (112) and which have magnetic anisotropy such that the easy magnetization direction becomes the thickness direction thereof, and which comprise a substance having topological antiferromagnetic properties. The particles (200) form a plurality of conductive parts (114) which are arranged at intervals in the in-plane direction of the insulating film (100) and are capable of conducting in the thickness direction thereof, and each of the conductive parts (114) is formed of a single particle (or a plurality of particles arranged in the thickness direction). Each of the particles (200) has a south pole region (604) and a north pole region (602) formed at both end portions in a direction along the easy magnetization direction, respectively, and the magnetic flux of the virtual magnetic field is concentrated in the south pole region (604) and the north pole region (602).

The invention belongs to the field of environmental monitoring, and discloses a preparation method of a nickel-based electrode with a spin pinning effect and application of the nickel-based electrode in chemical oxygen demand detection. A nickel substrate is subjected to ultrasonic treatment through hydrochloric acid and an organic solvent, cleaned and dried, a precursor layer is formed on the surface of the nickel substrate through an electro-deposition method or a hydrothermal method or an impregnation method, the precursor layer is converted into an antiferromagnetic or paramagnetic metal oxide layer through oxidation treatment, and the electrode with the spin pinning effect is prepared. The electrode is used as a working electrode in COD detection, under the action of an external magnetic field, a three-electrode system is used for electrochemical detection, and rapid and accurate determination of COD in a water body is realized. The preparation method of the nickel-based electrode with the spin pinning effect has the advantages of being simple and easy to operate and suitable for large-scale production, the stability and sensitivity of COD detection are further improved, and an efficient and reliable novel method is provided for water COD detection.

The invention discloses an antiferromagnetic metal single crystal with a three-dimensional stacking ordered structure and a preparation method of the antiferromagnetic metal single crystal. The preparation method comprises the following steps: uniformly mixing Fe powder, Co powder, Ge powder and Te powder, and then loading the mixture into a quartz tube together with a transport agent; putting the sealed quartz tube into a double-temperature-zone tubular furnace for calcining to obtain the antiferromagnetic metal single crystal; a unit cell of the antiferromagnetic metal single crystal is formed by stacking a plurality of layer structures layer by layer, and each layer structure is provided with two Te layers, a Ge layer and a Fe / Co layer, wherein the Ge layer and the Fe / Co layer are respectively positioned between the two Te layers; the plurality of layer structures are grouped in pairs to form a plurality of layer groups which are sequentially stacked, the two layer structures in the same layer group are in an AA stacking mode, and the two layer structures in the two adjacent layer groups are in an ordered staggered stacking mode. The antiferromagnetic metal single crystal has the characteristics of good cruising antiferromagnetism, neel temperature higher than room temperature, three-dimensional stacking ordered structure and the like, and promotes the development of related fields.

The application belongs to the technical field of multiferroic materials, and relates to a design method of a multiferroic material based on a vanadium-doped two-dimensional ferroelectric body and the multiferroic material. Single-layer NbOI2 primitive cells are expanded in different directions to obtain supercells of different sizes. Vanadium is used as a doping element to dope the supercells of different sizes, and the doping configurations of each supercell under different doping concentrations are obtained. The doping configuration with the lowest total energy of the ferromagnetic state and the antiferromagnetic state under each doping concentration is used as the ground state configuration of the doping concentration. The band gap Eg and the spontaneous ferroelectric polarization intensity along the b-axis of the ground state configuration under different doping concentrations are calculated. A double-Y-axis curve graph is drawn with the doping concentration as the horizontal coordinate and the spontaneous ferroelectric polarization intensity and the band gap Eg as the vertical coordinate, and the multiferroic phase region and the magnetic semimetal phase region are divided. The doping concentration-physical property evolution phase diagram is obtained, so that the corresponding doping concentration value range of the ground state configuration with the multiferroic phase of ferroelectricity and antiferromagnetism is obtained to design the multiferroic material.

The invention belongs to the technical field of magnesium alloy surface composite coatings, and particularly relates to a magnesium alloy surface non-magnetic iron-manganese collagen chitosan composite coating. The composite coating comprises a FeMn coating and a CaP / Col-CS coating, the FeMn coating is attached to the magnesium alloy substrate, and the CaP / Col-CS coating is attached to the FeMn coating. The preparation method comprises the following steps: preparing a FeMn coating on a clean and dry magnesium alloy substrate; and then a CaP coating and a Col-CS coating are prepared through a chemical conversion method. The polymer composite coating obtained by the invention not only has excellent corrosion resistance, but also can keep excellent biocompatibility; and meanwhile, the composite material also has antiferromagnetism and excellent mechanical properties which are necessary under an imaging monitoring condition. The structural design is reasonable, the preparation process is simple and controllable, the performance of the obtained product is excellent, and industrial application is facilitated.

In a method for manufacturing a magnetic laminate, a laminated film (601) having a ferromagnetic layer (631) and an antiferromagnetic layer (66) is formed, the ferromagnetic layer (631) and the antiferromagnetic layer (66) being in contact with each other in a first direction (Z) (step S1). Next, a magnetic field in the first direction (Z) is applied to the laminated film (601), and a magnetization-fixed layer (63), the magnetization direction of which is fixed with respect to the external magnetic field, is produced from the ferromagnetic layer (631) (step S2). After the application of the magnetic field is stopped, the laminated film (601) is heated at a temperature equal to or higher than the barrier temperature of the antiferromagnetic layer (66), and a magnetic laminate (6) is produced (step S3).

Disclosed are a magnon junction, magnon random access memory, microwave oscillator and detector, and electronic device. The magnon junction comprises: a first electrode layer formed by non-magnetic conductive material; a free magnetic layer arranged on the first electrode layer, formed by ferromagnetic conductive material; an antiferromagnetic barrier layer arranged on the free magnetic layer, formed by antiferromagnetic insulator material; a reference magnetic layer arranged on the antiferromagnetic barrier layer, formed by ferromagnetic conductive material; and a second electrode layer arranged on the reference magnetic layer, formed by non-magnetic conductive material. The reference magnetic layer has perpendicular magnetic anisotropy or perpendicular magnetic moment component, moment direction of which is fixed along a vertical direction; the free magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, moment direction of which is flippable along the perpendicular direction; the antiferromagnetic barrier layer has perpendicular magnetic anisotropy or perpendicular magnetic moment component.

In order to reduce the amount of rare earth metals used in a cold storage material for a cryogenic refrigerator, this cold storage material for a cryogenic refrigerator contains crystals of Mn(Nb1-xTax)2O6 (0 ≤ x ≤ 1). In the temperature range of 6K or lower, Mn(Nb1-xTax)2O6 is antiferromagnetic, and the volume specific heat, which is a specific heat per volume, is greater than the volume specific heat of lead.

This magnetic sensor is provided with an MR element disposed on an inclined surface, and a magnetic field generator. The magnetic field generator includes a ferromagnetic portion formed of a ferromagnetic material, and an antiferromagnetic portion formed of an antiferromagnetic material and exchange-coupled with the ferromagnetic portion. The ferromagnetic portion and the antiferromagnetic portion are stacked in a direction intersecting the inclined surface. At any point on the inclined surface, the angle formed by the inclined surface and the upper surface of the substrate changes according to the position of any point in the direction perpendicular to the upper surface of the substrate.

A magnetic sensor element (100) for determining a magnetic field includes a substrate (10), a heavy metal layer (12) laminated on the substrate (10), an antiferromagnetic layer (14) laminated on the heavy metal layer (12) and composed of a first antiferromagnetic (e.g., Mn3Sn) having an antiferromagnetic magnetic structure in which time reversal symmetry has been macroscopically broken, and a cap layer (16) laminated on the antiferromagnetic layer (14). In the heavy metal layer (12), when an electric current (I) flows in an in-plane direction, a spin current is generated in a direction perpendicular to the plane, and a spin orbit moment generated by the spin current acts on a magnetic sequence of a first antiferromagnetic body of the antiferromagnetic layer (14), thereby controlling the magnetic sequence. The read signal of the first antiferromagnetic body of the antiferromagnetic layer (14) is linearly responsive to the magnetic field within a predetermined magnetic field range including a zero magnetic field.

This magnetic sensor is provided with an insulating layer, and an MR element and a magnetic field generator which are arranged on the insulating layer. The magnetic field generating body includes a ferromagnetic part made of a ferromagnetic material having a positive magnetostrictive constant, and an antiferromagnetic part made of an antiferromagnetic material and exchange-coupled with the ferromagnetic part. The MR element and the magnetic field generating body are arranged in a first direction. The insulating layer and the magnetic field generating body are configured such that, when compressive stress in the second direction is applied to the insulating layer, compressive stress in a third direction orthogonal to the first direction and intersecting the second direction is applied to the magnetic field generating body.

A quantum transducer includes a three-dimensional cavity resonator; a stack disposed in the three-dimensional cavity resonator, including a nonmagnetic first insulator film and a ferromagnetic or antiferromagnetic second insulator film that are stacked on each other, and having an interface between the first insulator film and the second insulator film; a magnetic field applicator configured to apply, to the stack, a magnetic field having a component perpendicular to the interface; and a microwave transceiver configured to transmit and receive a microwave to and from the stack. The first insulator film and the second insulator film do not include a topological insulator. The second insulator film has an easy axis of magnetization along a first axis that is perpendicular to the interface. Laser light is emitted to the stack from a direction inclined with respect to the first axis.

This invention discloses a three-dimensional cobalt metal-organic complex, its preparation method, and its applications, belonging to the field of crystal materials technology. This invention uses 2,5-diketopiperazine-N,N'-diacetic acid and 4,4'-bipyridine as raw materials with cobalt ions to prepare a compound with the chemical formula [Co(DPDA)(4,4'-bpy)]. n A three-dimensional cobalt-organic metal complex. It has a six-connected three-dimensional network structure with dual-core [Co2(COO)2] structural units, and its topological symbol is {3 12 0.4 24 0.5 9 Furthermore, the aforementioned three-dimensional cobalt metal-organic complex can rapidly activate peroxymonosulfate to effectively degrade dyes. It can degrade methylene blue, malachite green, and crystal violet to over 95.0% within 5 minutes, without producing toxic byproducts during the degradation process, and exhibits good reusability. Additionally, the synthesis conditions of the three-dimensional cobalt metal-organic complex are mild, the steps are simple, and it possesses excellent structural stability, good thermal stability, and antiferromagnetism at high temperatures.

The application discloses a nanocrystal antiferromagnetic material, a preparation method and application, and the material is a cobalt-nickel-silicon (Co-Ni-Si) ternary polycrystal material, the chemical composition of which is composed of three elements of cobalt (Co), nickel (Ni) and silicon (Si), and the atomic number ratio of the cobalt, the nickel and the silicon is (33+ / -1):(21+ / -1):(46+ / -1). The preparation method comprises the following steps: (1) dosing; (2) packaging; (3) chemical vapor transport reaction; and (4) sampling. The antiferromagnetic material has wide application in preparation of spin electronic devices, such as magnetic tunnel junctions, spin valves, magnetic random access memories and magnetic sensors; and the material is used as an antiferromagnetic pinning layer, a reference layer or an active layer based on antiferromagnetism in the spin electronic devices.