An electric read-write memory device based on 180-degree flipping of antiferromagnetic nèel vector, preparation method and read-write method

Abstract

The application discloses an electric read-write memory device based on 180-degree flip of anti-ferromagnetic Neel vector, a preparation method and a read-write method. The electric read-write memory device comprises a substrate layer, an anti-ferromagnetic layer and a spin source layer which are sequentially stacked from bottom to top and constitute a heterostructure. The material of the substrate layer is a single crystal wafer capable of epitaxially growing the anti-ferromagnetic layer. The material of the anti-ferromagnetic layer is a collinear anti-ferromagnetic material with abnormal Hall effect or a staggered magnet with abnormal Hall effect. The material of the spin source layer has a spin current generation capability. The memory utilizes a current pulse to drive 180-degree flip of the Neel vector. The Neel vector before and after the 180-degree flip has two abnormal Hall resistance states of high and low, and can be used for storing information "0" and "1". The application not only enriches the connotation of the interaction between the spin current and the anti-ferromagnetic Neel vector, but also lays a foundation for constructing a high-density, high read-write speed and low-power nonvolatile magnetic random memory.

Description

Technical Field

[0001] This invention relates to an electrically readable and writable antiferromagnetic storage device, specifically to an electrically readable and writable storage device based on a 180-degree flip of the antiferromagnetic Nell vector, its preparation method, and its read / write method. The device utilizes spin-orbit torque to drive the antiferromagnetic Nell vector to flip 180 degrees and uses the anomalous Hall effect to read out the antiferromagnetic Nell vector. This invention belongs to the field of electronic information materials. Background Technology

[0002] Spintronic devices utilize the spin degree of freedom of electrons, demonstrating enormous potential in developing and constructing novel non-volatile information storage devices with high speed, low power consumption, and high density, aligning with the development requirements of big data, cloud computing, and artificial intelligence. In recent years, antiferromagnetic materials, due to their advantages such as the absence of stray fields, high intrinsic frequency, and resistance to external magnetic field interference, have become an important development direction for ultrafast and ultra-high-density information storage, and are expected to be applied to high-frequency electronic devices for electromagnetic threat mitigation. Given the characteristics of antiferromagnetic materials—zero net magnetic moment and insensitivity to external magnetic fields—achieving the electrical reversal and detection of the antiferromagnetic Nell vector is a key scientific problem in realizing information reading and writing in antiferromagnetic magnetic storage technology. However, current writing technologies are limited to electrically driving the antiferromagnetic Nell vector to flip 90 or 120 degrees, and readout technologies are limited to utilizing magnetoresistance. Specifically, this is achieved using field-like torques in antiferromagnetic CuMnAs or antiferromagnetic Mn2Au with broken antiferromagnetic sublattice symmetry, or using damping-like torques in antiferromagnetic NiO and antiferromagnetic Fe2O3, requiring the use of difficult-to-integrate eight-terminal devices. Electrically driving the antiferromagnetic Nell vector to flip 180 degrees and electrically read it out is a highly desired but yet unrealized technology closely related to the electrical operation and reading of the "0" and "1" bit states in information technology, possessing the potential of two-terminal devices. Summary of the Invention

[0003] The purpose of this invention is to provide an electrical read / write storage device and method based on the 180-degree flipping of the antiferromagnetic Nell vector. The invention utilizes spin-orbit torque to drive the antiferromagnetic Nell vector to flip 180 degrees, and uses the anomalous Hall effect to read the antiferromagnetic Nell vector. This 180-degree flipping of the antiferromagnetic Nell vector realizes an electrically readable and writable storage device, enriching the understanding of the interaction between spin current and the antiferromagnetic Nell vector, and laying the foundation for constructing high-density, high-speed, and low-power non-volatile magnetic random access memory.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] In a first aspect, the present invention provides an electrical read / write storage device, comprising: a substrate layer, an antiferromagnetic layer, and a spin source layer that are stacked sequentially from bottom to top and constitute a heterogeneous structure;

[0006] The substrate layer is a single-crystal substrate on which an antiferromagnetic layer can be epitaxially grown;

[0007] The material of the antiferromagnetic layer is a collinear antiferromagnetic material with an anomalous Hall effect or an interlaced magnet with an anomalous Hall effect;

[0008] The material of the spin source layer has the ability to generate spin flow.

[0009] In the aforementioned electrical read / write storage devices, the single-crystal substrate is an alumina substrate (Al2O3), a magnesium oxide substrate (MgO), a lanthanum aluminate substrate (LaAlO3), or a lead magnesium niobate-lead titanate substrate (Pb(MgO)). 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3 or SrTiO3-based strontium titanate sheets.

[0010] In the aforementioned electrical read / write storage devices, the collinear antiferromagnetic material with anomalous Hall effect or the interlaced magnet material with anomalous Hall effect is Mn5Si3 or CrSb.

[0011] In the aforementioned electrical read / write storage device, the thickness of the antiferromagnetic layer is 3–50 nm.

[0012] In the aforementioned electrical read / write storage devices, the material of the spin source layer is a heavy metal such as Pt, Ta, or W.

[0013] In the aforementioned electrical read / write storage devices, the thickness of the spin source layer is 1–20 nm.

[0014] The aforementioned electrical read / write storage device also includes a first electrode, a second electrode, a third electrode, and a fourth electrode;

[0015] With the stacking direction as the vertical direction, the first electrode and the second electrode are respectively disposed on opposite sides of the first horizontal direction, and the third electrode and the fourth electrode are respectively disposed on opposite sides of the second horizontal direction, wherein the first horizontal direction and the second horizontal direction are perpendicular.

[0016] In a second aspect, the present invention provides a method for manufacturing the electrical read / write storage device according to any one of the above claims, comprising:

[0017] The antiferromagnetic layer is formed on the surface of the substrate layer;

[0018] The spin source layer is formed on the surface of the antiferromagnetic layer away from the substrate layer.

[0019] In the above preparation method, forming the antiferromagnetic layer includes: performing a film-forming treatment on the surface of the substrate layer;

[0020] The formation of the spin source layer includes: performing a film-forming treatment on the surface of the antiferromagnetic layer.

[0021] Thirdly, the present invention provides an electrical read / write method for the electrical read / write storage device described in any of the above claims, comprising:

[0022] With the stacking direction as the vertical direction, a pulsed current along the first horizontal direction is applied to the memory device. The pulsed current flowing through the spin source layer generates transverse spin polarization through the spin Hall effect and is vertically injected into the antiferromagnetic layer. This generates a spin orbital torque on the antiferromagnetic Nell vector in the antiferromagnetic layer. Under the action of a magnetic field parallel to the first horizontal direction, the spin orbital torque drives the Nell vector to flip 180 degrees, thereby realizing the electrical writing of the memory device.

[0023] An anomalous Hall voltage in a second horizontal direction, perpendicular to the first horizontal direction, is read to achieve electrical readout of the storage device.

[0024] The present invention has the following beneficial effects:

[0025] This invention provides an electrical read / write storage device based on a 180-degree flip of an antiferromagnetic Nell vector. It utilizes spin-orbit torque to drive the antiferromagnetic Nell vector to flip 180 degrees, and uses the anomalous Hall effect to read the antiferromagnetic Nell vector. It has the following advantages: the antiferromagnetic material provides resistance to magnetic field interference and fast operation speed; the ratio of anomalous Hall coercivity to critical write current density is more than four times that of traditional ferromagnetic systems, resulting in low power consumption. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the principle of an electrical read / write storage device based on a 180-degree flip of an antiferromagnetic Nell vector, provided in an embodiment of the present invention. The markings in the diagram are as follows: 1-substrate layer; 2-antiferromagnetic layer; 3-spin source layer; 4-positive terminal of write current; 5-negative terminal of write current; 6-positive terminal of read voltage; 7-negative terminal of read voltage; 8-magnetic field along the direction of write current.

[0027] Figure 2 This is a schematic diagram of the device structure of an electrical read / write storage device based on a 180-degree flip of the antiferromagnetic Nell vector, provided in an embodiment of the present invention. The various markings in the figure are... Figure 1 Consistent.

[0028] Figure 3 In Embodiment 1 of the present invention, in an Al2O3 (0001) substrate / collinear antiferromagnetic thin film Mn5Si3 (6nm) / heavy metal Pt (10nm) memory device, in Figure 1 When positive and negative current pulses of different magnitudes are applied to terminals 4-5, the voltage changes at terminals 6-7 are recorded using a nanovolt voltmeter.

[0029] Figure 4 In Embodiment 2 of the present invention, in a LaAlO3 (110) substrate / collinear antiferromagnetic thin film CrSb (40nm) / heavy metal Pt (5nm) memory device, in Figure 1 When positive and negative current pulses of different magnitudes are applied to terminals 4-5, the voltage changes at terminals 6-7 are recorded using a nanovolt voltmeter. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0031] Hereinafter, the terms "first," "second," etc., are used for descriptive convenience only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature.

[0032] Furthermore, in the embodiments of this application, directional terms or positional relationships such as "upper," "lower," "left," "right," "horizontal," and "vertical" are based on the orientation or positional relationships shown in the accompanying drawings. They are only for the purpose of facilitating the description of the present invention and simplifying the description, and are not intended to indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0033] The following description, in conjunction with the accompanying drawings, details the electrical read / write storage device based on the 180-degree flip of the antiferromagnetic Nell vector provided in the embodiments of the present invention.

[0034] In a first aspect, the present invention provides an electrical read / write storage device, such as... Figure 1 As shown, it includes: a substrate layer 1, an antiferromagnetic layer 2, and a spin source layer 3, which are stacked sequentially from bottom to top and form a heterostructure; the substrate layer 1 is made of a single-crystal substrate on which the antiferromagnetic layer 2 can be epitaxially grown; the antiferromagnetic layer 2 is made of a collinear antiferromagnetic material with an anomalous Hall effect or an interlaced magnet with an anomalous Hall effect; the spin source layer 3 has the ability to generate spin current.

[0035] The specific implementation method of the electrical read / write storage device of the present invention is as follows: Figure 1As shown, a pulsed current is passed through terminals 4-5 of the electrical read / write storage device. The pulsed current flowing through the heavy metal layer 3 generates transverse spin polarization through the spin Hall effect and is vertically injected into the antiferromagnetic layer 2, generating a spin-orbit torque on the antiferromagnetic Nell vector in the antiferromagnetic layer 2. Under the action of an auxiliary magnetic field parallel to terminals 4-5, the spin-orbit torque drives the Nell vector to flip 180 degrees. The 180-degree flip of the Nell vector is read by reading the anomalous Hall voltage at terminals 6-7. This invention utilizes the spin-orbit torque to electrically drive the antiferromagnetic Nell vector to flip 180 degrees and utilizes the anomalous Hall effect to electrically read the direction of the antiferromagnetic Nell vector before and after the 180-degree flip.

[0036] According to the present invention, single-crystal substrates capable of epitaxially growing antiferromagnetic layers include, but are not limited to, alumina substrates (Al2O3), magnesium oxide substrates (MgO), lanthanum aluminate substrates (LaAlO3), and lead magnesium niobate-lead titanate substrates (Pb(MgO)). 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3 (PMN-PT), SrTiO3 substrate; in specific embodiments of the present invention, the single crystal substrate on which the antiferromagnetic layer can be epitaxially grown is Al2O3 (0001) or LaAlO3 (110). The thickness of the substrate layer is not limited, such as 0.5-1 mm, 0.5 mm or 1 mm.

[0037] According to the present invention, the collinear antiferromagnetic material with anomalous Hall effect can be Mn5Si3 or CrSb; preferably, the thickness of the antiferromagnetic layer 2 is in the range of 3 to 50 nm, including but not limited to 6 to 40 nm, 6 nm or 40 nm.

[0038] According to the present invention, the material of the spin source layer 3 includes, but is not limited to, heavy metals Pt, Ta or W; preferably, the thickness of the spin source layer 3 is in the range of 1 to 20 nm, including but not limited to 5 to 10 nm, 5 nm or 10 nm.

[0039] According to the present invention, the electrical read / write storage device further includes a first electrode, a second electrode, a third electrode, and a fourth electrode; with the stacking direction as the vertical direction, the first electrode and the second electrode are respectively disposed on opposite sides of a first horizontal direction (i.e., the first electrode and the second electrode are respectively disposed on opposite sides of end 4-5), the third electrode and the fourth electrode are respectively disposed on opposite sides of a second horizontal direction, and the first horizontal direction and the second horizontal direction are perpendicular (i.e., the third electrode and the fourth electrode are respectively disposed on opposite sides of end 6-7).

[0040] Preferably, such as Figure 2As shown, the electrical read / write storage device is cross-shaped, with the first and second electrodes respectively disposed on opposite sides of one cross edge, and the third and fourth electrodes respectively disposed on opposite sides of the other cross edge. The first and second electrodes are used to apply a pulsed write current; the third and fourth electrodes are used to read the anomalous Hall voltage. Specifically, the substrate layer, antiferromagnetic layer, and spin source layer, stacked sequentially from bottom to top to form a heterostructure, can be a four-terminal cross bar, such as a four-terminal cross bar with dimensions of 4μm (voltage end) × 6μm (current end); the first, second, third, and fourth electrodes are connected to the four ends of the four-terminal cross bar.

[0041] The materials of the first electrode, second electrode, third electrode and fourth electrode are not limited. Preferably, the first electrode, second electrode, third electrode and fourth electrode are all Ti / Au composite electrodes, wherein the thickness of the Ti metal layer is 10nm and the thickness of the Au layer is 70nm.

[0042] In a second aspect, the present invention provides a method for fabricating an electrical read / write storage device, comprising: forming an antiferromagnetic layer 2 on the surface of a substrate layer 1; and forming a spin source layer 3 on the surface of the antiferromagnetic layer 2 away from the substrate layer 1.

[0043] According to the present invention, forming the antiferromagnetic layer 2 includes: performing a film deposition process on the surface of the substrate layer 1. The film deposition process can specifically be a deposition process, which can be selected according to the film material, such as magnetron sputtering deposition of Mn5Si3 or CrSb. For example, if the material of the antiferromagnetic layer 2 is Mn5Si3, a Mn5Si3 thin film is deposited using a co-sputtering method with a Mn target and a Si target; specifically, the deposition conditions are as follows: Mn5Si3 thin films were deposited on Al2O3(0001) substrates at a high speed; the base vacuum before cavity sputtering of the Mn5Si3 thin film was 5 × 10⁻⁶. -8 Torr, the argon gas pressure during sputtering was 3 mtorr; after the Mn5Si3 thin film was deposited, it was heated to 600℃ and annealed for 2 hours. The antiferromagnetic layer 2 was made of CrSb, and the CrSb thin film was deposited using a co-sputtering method with Cr and Sb targets; specifically, the deposition conditions were as follows: CrSb thin films were deposited on a LaAlO3(110) substrate at a speed of 7 × 10⁻⁶ m / s. The base vacuum before cavity sputtering of the CrSb thin film was 7 × 10⁻⁶ m / s. -8 Torr, the argon gas pressure during sputtering is 3 mtorr; after film deposition, the temperature is raised to 470℃ for annealing for 30 minutes. Formation of the spin source layer 3 includes: film deposition treatment on the surface of the antiferromagnetic layer 2. The film deposition treatment method can be film deposition, and the specific method can be selected according to the film material, such as magnetron sputtering deposition of heavy metal Pt; specifically, the deposition conditions are as follows: the base vacuum before sputtering the Pt film in the cavity is 5 × 10⁻⁶ mtorr. -8Torr, the argon gas pressure during sputtering is 3 mtorr.

[0044] Thirdly, the present invention provides an electrical read / write method for an electrical read / write storage device, comprising: applying an electrical read / write force along a first horizontal direction (e.g., with the stacking direction as the vertical direction) to the storage device. Figure 1 The pulsed current (at terminals 4-5) flowing through the spin source layer 3 generates transverse spin polarization through the spin Hall effect and is vertically injected into the antiferromagnetic layer 2. This generates a spin orbital torque on the antiferromagnetic Nell vector in the antiferromagnetic layer 2, parallel to the first horizontal direction (e.g., ...). Figure 1 Under the influence of the auxiliary magnetic field (8) along the direction of the writing current, the spin orbital torque drives the Nell vector to flip 180 degrees, realizing the electrical writing of the memory device; reading is performed in the second horizontal direction (such as...). Figure 1 The anomalous Hall voltage at terminals 6-7 is used to realize the electrical readout of the memory device by making the second horizontal direction perpendicular to the first horizontal direction.

[0045] In this invention, based on the antiferromagnetic Nell's temperature of each layer of material in the electrical read / write memory device, a suitable temperature is selected for reading and writing the electrical memory device. For example, in one embodiment of this invention, the temperature of the electrical read / write memory device is lowered to 180K and an auxiliary magnetic field is applied, because the antiferromagnetic Nell's temperature of Mn5Si3 is below room temperature; in another specific embodiment of this invention, the temperature of the electrical read / write memory device is maintained at room temperature while an auxiliary magnetic field is applied, because the antiferromagnetic Nell's temperature of CrSb is above room temperature. In this invention, room temperature refers to 10–30°C, preferably 15–30°C, and more preferably 20–25°C.

[0046] This invention relates to an electrical read / write memory device based on a 180-degree flip of an antiferromagnetic Nell vector. The Nell vector is driven by a current pulse to flip 180 degrees, resulting in two anomalous Hall resistance states—one high and one low—before and after the flip, which can be used to store information "0" and "1". The write current pulse flows through the spin source layer, generating a spin current. This spin current acts on the Nell vector in the antiferromagnetic layer, producing a spin-orbit torque that drives the Nell vector to flip 180 degrees, thus achieving electrical writing to the memory. The read current pulse flows through the antiferromagnetic layer, utilizing the anomalous Hall effect to generate a potential difference laterally. The 180-degree flip of the Nell vector creates a high and low lateral potential difference, enabling electrical reading from the memory. In a specific embodiment of this invention, a change in Hall voltage occurs when the absolute value of the pulse current reaches 30 mA or more, indicating the formation of a 180-degree flip of the antiferromagnetic Nell vector. This invention utilizes a 180-degree flip of the antiferromagnetic Nell vector to realize an electrically readable and writable storage device, which not only enriches the connotation of the interaction between spin current and antiferromagnetic Nell vector, but also lays the foundation for building a high-density, high-speed, low-power non-volatile magnetic random access memory.

[0047] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0048] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; and the materials and reagents used are commercially available unless otherwise specified.

[0049] Example 1: An Al2O3(0001) / Mn5Si3(6nm) / Pt(10nm) electrical read / write storage device based on an antiferromagnetic Nell vector 180-degree flip.

[0050] Mn5Si3 (6nm) / Pt (10nm) heterojunction samples were deposited on an Al2O3 (0001) substrate (0.5mm) by magnetron sputtering.

[0051] At 465℃, using a co-sputtering method with Mn and Si targets, Mn5Si3 thin films were deposited on Al2O3(0001) substrates at a speed of [missing information]. The base vacuum before cavity sputtering of the Mn5Si3 thin film was 5 × 10 [missing information]. -8 Torr, the argon gas pressure during sputtering was 3 mtorr. After the Mn5Si3 thin film was deposited, the temperature was raised to 600℃ for annealing for 2 hours. After cooling to room temperature, 10 nm Pt was deposited. The base vacuum before sputtering the Pt thin film in the chamber was 5 × 10⁻⁶ mtorr. -8 Torr, the argon gas pressure during sputtering is 3 mtorr.

[0052] Using ultraviolet exposure and argon ion etching micro-nano fabrication technology, the above-mentioned Mn5Si3 (6nm) / Pt (10nm) heterojunction sample was processed into a 4μm×6μm four-terminal cross strip. Then, using ultraviolet exposure, electron beam evaporation and stripping micro-nano fabrication technology, Ti (10nm) / Au (70nm) electrodes were prepared and connected to the four-terminal cross strip to form an electrical read-write storage device.

[0053] During testing, an ultrasonic aluminum wire bonding machine was used to connect the 4-5 current terminals and 6-7 voltage terminals of the electrical read / write memory device to an ammeter and a nanovolt voltmeter.

[0054] The electrical read / write storage device is placed inside the low-temperature sample chamber, which is then placed within the magnetic field applied by the electromagnet along ends 4-5.

[0055] Reduce the temperature of the electrical read / write storage device to 180K and apply an auxiliary magnetic field of 0.2kOe or -0.2kOe along terminals 4-5.

[0056] like Figure 3 As shown, a 1ms pulse write current with a magnitude varying from +46mA to -46mA and back to +46mA is applied to the 4-5 current terminal. After waiting 10s, a 2mA DC read current is applied to the 4-5 current terminal, and the Hall voltage at the 6-7 voltage terminal is recorded. It can be seen that a change in Hall voltage occurs when the absolute value of the pulse current reaches 30mA or more, indicating a 180-degree flip of the antiferromagnetic Nell vector. For auxiliary magnetic fields of opposite polarities (0.2kOe and -0.2kOe), the polarities of the 180-degree flip of the antiferromagnetic Nell vector induced by the positive and negative pulse currents are opposite, which conforms to the basic symmetry requirement of the spin-orbit torque reversal magnetic moment. The ratio of the anomalous Hall coercivity to the critical write current density of the electrical read / write memory device in this example is 4mTcm. 2 MA -1 The ratio of the anomalous Hall coercivity to the critical writing current density in traditional ferromagnetic systems is approximately 1 mT / cm. 2 MA -1 about.

[0057] The mechanism of the pulsed write current driving the 180-degree flip of the antiferromagnetic Nell vector is as follows: The pulsed current flowing through the Pt layer generates transverse spin polarization through the spin Hall effect and is injected vertically into the antiferromagnetic Mn5Si3, generating a spin-orbit torque on the Nell vector of the antiferromagnetic Mn5Si3. This spin-orbit torque induces a slight deflection of the Nell vector of Mn5Si3 in the transverse spin polarization direction, thereby generating an antiferromagnetic exchange torque under the action of the antiferromagnetic exchange field, driving the Nell vector to rotate. An auxiliary field can apply Zeeman energy to the small net magnetic moment generated by the Dzyaloshinskii-Moriya interaction in the antiferromagnetic Mn5Si3, thereby breaking the symmetry of the 180-degree flip of the Mn5Si3 Nell vector and achieving a decisive 180-degree flip of the Nell vector.

[0058] Example 2: CrSb (40nm) / Pt (5nm) electrical read / write storage device based on 180-degree antiferromagnetic Nell vector flip.

[0059] A CrSb (40 nm) / Pt (5 nm) heterojunction sample was deposited on a LaAlO3 (110) substrate (0.5 mm) by magnetron sputtering.

[0060] At 350℃, using a co-sputtering method with Cr and Sb targets, CrSb thin films were deposited on a LaAlO3(110) substrate at a high speed. The base vacuum before cavity sputtering of the CrSb thin film was 7 × 10⁻⁶. -8Torr, the argon gas pressure during sputtering was 3 mtorr. After film deposition, the temperature was raised to 470℃ for annealing for 30 minutes. After cooling to room temperature, 5 nm Pt was deposited. The base vacuum before sputtering the Pt film in the chamber was 5 × 10⁻⁶ mtorr. -8 Torr, the argon gas pressure during sputtering is 3 mtorr.

[0061] Using ultraviolet exposure and argon ion etching micro-nano fabrication technology, the above-mentioned CrSb (40nm) / Pt (5nm) heterojunction sample was processed into a 4μm×6μm four-end cross strip to become the electrical read / write storage device.

[0062] During testing, an ultrasonic aluminum wire bonding machine was used to connect the 4-5 current terminals and 6-7 voltage terminals of the electrical read / write storage device to an ammeter and a nanovolt voltmeter.

[0063] The electrical read / write storage device is placed inside the sample cavity, which is then placed within the magnetic field applied by the electromagnet along ends 4-5.

[0064] An auxiliary magnetic field of 0.8 kOe or -0.8 kOe is applied along terminals 4-5 at room temperature to the electrical read / write storage device.

[0065] Experimental results are as follows Figure 4 As shown in Example 1, a 1ms pulse write current with a magnitude varying from +46mA to -46mA and back to +46mA was applied to the 4-5 current terminals. After waiting 10s, a 2mA DC read current was applied to the 4-5 current terminals, and the Hall voltage at the 6-7 voltage terminals was recorded. It can be seen that when the absolute value of the pulse current reaches 30mA or more, a change in Hall voltage occurs, indicating a 180-degree flip of the antiferromagnetic Nell vector. For auxiliary magnetic fields of opposite polarities (0.8kOe and -0.8kOe), the polarities of the 180-degree flip of the antiferromagnetic Nell vector induced by the positive and negative pulse currents are opposite, which conforms to the basic symmetry requirement of the spin-orbit torque reversal magnetic moment. The ratio of the anomalous Hall coercivity to the critical write current density of the electrical read / write memory device in this example is 5mT / cm. 2 MA -1 The ratio of the anomalous Hall coercivity to the critical writing current density in traditional ferromagnetic systems is approximately 1 mT / cm. 2 MA -1 about.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electrical read / write storage device, characterized in that, include: A substrate layer, an antiferromagnetic layer, and a spin source layer are stacked sequentially from bottom to top to form a heterogeneous structure; The substrate layer is a single-crystal substrate on which an antiferromagnetic layer can be epitaxially grown; The material of the antiferromagnetic layer is a collinear antiferromagnetic material with an anomalous Hall effect or an interlaced magnet with an anomalous Hall effect; The material of the spin source layer has the ability to generate spin flow.

2. The electrical read / write storage device according to claim 1, characterized in that: The single-crystal substrate is an alumina substrate (Al2O3), a magnesium oxide substrate (MgO), a lanthanum aluminate substrate (LaAlO3), or a lead magnesium niobate-lead titanate substrate (Pb(Mg)). 1 / 3 Nb 2 / 3 ) 0.7 Ti 0.3 O3 or SrTiO3-based strontium titanate sheets.

3. The electrical read / write storage device according to claim 1 or 2, characterized in that: The collinear antiferromagnetic material exhibiting the anomalous Hall effect or the interlaced magnet material exhibiting the anomalous Hall effect is Mn5Si3 or CrSb.

4. The electrical read / write storage device according to any one of claims 1-3, characterized in that: The thickness of the antiferromagnetic layer is 3–50 nm.

5. The electrical read / write storage device according to any one of claims 1-4, characterized in that: The material of the spin source layer is a heavy metal such as Pt, Ta, or W.

6. The electrical read / write storage device according to any one of claims 1-5, characterized in that: The thickness of the spin source layer is 1–20 nm.

7. The electrical read / write storage device according to any one of claims 1-6, characterized in that: It also includes a first electrode, a second electrode, a third electrode, and a fourth electrode; With the stacking direction as the vertical direction, the first electrode and the second electrode are respectively disposed on opposite sides of the first horizontal direction, and the third electrode and the fourth electrode are respectively disposed on opposite sides of the second horizontal direction, wherein the first horizontal direction and the second horizontal direction are perpendicular.

8. A method for preparing an electrical read / write storage device according to any one of claims 1-7, characterized in that, include: The antiferromagnetic layer is formed on the surface of the substrate layer; The spin source layer is formed on the side of the antiferromagnetic layer away from the substrate layer.

9. The method for preparing the electrical read / write storage device according to claim 8, characterized in that: The formation of the antiferromagnetic layer includes: performing a film-forming process on the surface of the substrate layer; The formation of the spin source layer includes: performing a film-forming treatment on the surface of the antiferromagnetic layer.

10. The electrical read / write method of the electrical read / write storage device according to any one of claims 1-7, comprising: With the stacking direction as the vertical direction, a pulsed current along the first horizontal direction is applied to the memory device. The pulsed current flowing through the spin source layer generates transverse spin polarization through the spin Hall effect and is vertically injected into the antiferromagnetic layer. This generates a spin orbital torque on the antiferromagnetic Nell vector in the antiferromagnetic layer. Under the action of a magnetic field parallel to the first horizontal direction, the spin orbital torque drives the Nell vector to flip 180 degrees, thereby realizing the electrical writing of the memory device. An anomalous Hall voltage in a second horizontal direction, perpendicular to the first horizontal direction, is read to achieve electrical readout of the storage device.

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