Vertical magnetization antiferromagnetic magnetic memory without external field assistance and its storage method

Abstract

The application relates to a vertical magnetization anti-ferromagnetic magnetic memory without external field assistance and a storage method thereof, which comprises an anti-ferromagnetic layer, an insulating layer and a heavy metal layer from top to bottom, two groups of write currents of the anti-ferromagnetic layer and the heavy metal layer are perpendicular to each other in space, the size and direction of the two groups of write currents of the anti-ferromagnetic layer and the heavy metal layer are controlled, the upward or downward state of a Neel vector in the anti-ferromagnetic layer is controlled, and the Neel vector state represents different information of storage. The Neel vector of an anti-ferromagnetic device is regulated by using direct current to realize data writing, improve the arrangement density of a storage unit array, and save energy consumption. The vertical magnetization anti-ferromagnetic magnetic random storage unit has higher magnetic moment flip speed, better storage stability, simple structure, high speed, anti-stray field disturbance and non-volatility, and the storage unit is especially faster in reading and writing speed.

Description

Technical Field

[0001] This invention relates to a storage technology, and more particularly to a vertically magnetized antiferromagnetic memory and its storage method that do not require external field assistance. Background Technology

[0002] Magnetic Random Access Memory (MRAM) refers to random access memory that stores data based on changes in magnetoresistance or magnetization state. It uses different magnetization states or the resulting differences in magnetoresistance to record 0s and 1s. As long as no external magnetic field or control current is applied, its magnetization state remains unchanged, and the recorded information remains unchanged. Magnetic random access memory offers high-speed read / write capabilities and high integration density, providing a new method for achieving faster information reading and writing speeds, higher data access density, lower power consumption, and greater portability in electronic storage devices. Furthermore, due to its non-volatility, low power consumption, and radiation resistance, it has important applications in computers, industrial automation, aerospace, and other industries. Currently, the main types of magnetic random access memory are: magnetic field-driven MRAM and current-driven spin-torque-driven MRAM (STT-MRAM). For the current-driven type, the magnetization reversal speed using STT is very fast, but the critical current density for magnetization reversal is relatively high, increasing the device's power consumption. In recent years, another driving method based on current-driven magnetization reversal has been proposed: using spin-orbit torque. Because the injection of current into the heavy metal layer generates a spin current perpendicular to the current direction due to spin-orbit coupling, this spin current also acts on the magnetic material adjacent to the heavy metal layer, thereby generating spin-orbit torque and changing the magnetization state of the magnetic layer. This is simply referred to as spin-orbit torque driven MRAM (SOT-MRAM). In previous studies, due to the difficulty of reversing the magnetization state and the limitations of studying the reversal mechanism, the magnetic layer was usually made of ferromagnetic or subferromagnetic materials.

[0003] Compared to traditional ferromagnetic and ferrimagnetic materials, antiferromagnetic materials, due to their strong interatomic coupling fields and zero net magnetic moment, offer faster information writing and greater stability against external interference. While magnetic memory devices provide non-volatile storage under many operating conditions, there is a need for more robust data storage in such devices, ensuring data retention even after exposure to adverse conditions, such as unintended stray fields. Summary of the Invention

[0004] To address the problem of reversing the magnetization state in spin-orbit torque-driven magnetic random access memory (SRAM), a novel vertically magnetized antiferromagnetic RAM and its storage method are proposed, requiring no external field assistance. This method utilizes a current-controlled SOT-MRAM based on antiferromagnetic materials—specifically, DC current controlling the Néel vector of an antiferromagnetic device—to achieve data writing, thereby increasing the array density of memory cells and saving energy. It also improves the magnetic moment reversal speed and storage stability of traditional magnetic memories. The proposed device structure enables stable data writing without external field assistance, solely through current.

[0005] The technical solution of the present invention is as follows: a vertically magnetized antiferromagnetic memory that does not require external field assistance, comprising an antiferromagnetic layer, an insulating layer and a heavy metal layer from top to bottom. The two sets of write currents of the antiferromagnetic layer and the heavy metal layer are perpendicular to each other in space. By controlling the magnitude and direction of the two sets of write currents of the antiferromagnetic layer and the heavy metal layer, the state of the Néel vector in the antiferromagnetic layer can be controlled to be upward or downward. The state of the Néel vector represents different stored information.

[0006] Preferably, the antiferromagnetic layer is made of a rare earth-transition metal amorphous alloy, wherein the rare earth element is one of Tb, Gd, or Ho, and the transition metal is an antiferromagnetic material with perpendicular anisotropy.

[0007] Preferably, the heavy metal layer is a heavy metal element layer with a large spin Hall angle, and the element is one of the nonmagnetic heavy metals Ta, W, Pt, Au, and Ir, or a nonmagnetic alloy formed by the nonmagnetic heavy metal and other transition metals.

[0008] Preferably, the thicknesses of the antiferromagnetic layer, the insulating layer, and the heavy metal layer are all in the nanometer range.

[0009] Preferably, the thickness of the antiferromagnetic layer is less than 3 nm.

[0010] A storage method for a vertically magnetized antiferromagnetic magnetic memory without external field assistance is disclosed. When current is passed through the antiferromagnetic layer of the vertically magnetized antiferromagnetic magnetic memory, an alternating field-like torque is generated. When current flows through the heavy metal layer of the magnetic memory, all electrons move in the opposite direction to the current. The spin direction of the electrons depends on the direction of electron motion due to the spin Hall effect, thereby generating a damped spin orbital torque that acts on the magnetic moment of the magnetic material in the antiferromagnetic layer. The coupling of the two torques in the antiferromagnetic layer realizes the reversal of the antiferromagnetic magnetic moment. When the Néel vector in the antiferromagnetic layer is upward, i.e., positive, the state value of the storage cell in the insulating layer is defined as 1; when the Néel vector is downward, i.e. negative, the state value of the storage cell is defined as 0.

[0011] Furthermore, the center of the vertically magnetized antiferromagnetic magnetic memory is the center of the three-dimensional structure, the thickness of the upper and lower layers is in the z-direction, the direction towards the heavy metal layer is positive, the direction of the write current to the heavy metal layer is in the x-direction, and the direction of the write current to the antiferromagnetic layer is in the y-direction; specifically, it includes the following steps:

[0012] A: When it is necessary to rewrite the magnetization state in the antiferromagnetic information storage point, a direct current is simultaneously applied to both the heavy metal layer and the antiferromagnetic layer, with a current magnitude of 1×10⁻⁶. 7 ~1×10 9 A / cm 2 ;

[0013] B: The spin current generated by the DC current passed through the heavy metal layer enters the antiferromagnetic layer from the heavy metal layer. Together with the spin current generated by the DC current passed through the antiferromagnetic layer in the antiferromagnetic layer, it causes the magnetic moment in the antiferromagnetic layer to reverse.

[0014] C: When a DC current is continuously applied and the spin Hall angle of the heavy metal layer is positive, the steady state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is +x and the direction of I2 is +y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is +x and the direction of I2 is -y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is -x and the direction of I2 is +y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is -x and the direction of I2 is -y.

[0015] When the spin Hall angle of the heavy metal is negative, the stable state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is +x and the direction of I2 is +y; the stable state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is +x and the direction of I2 is -y; the stable state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is -x and the direction of I2 is +y; the stable state of the Néel vector in antiferromagnetic layer 1 tends to be in the -z direction when the direction of I1 is -x and the direction of I2 is -y.

[0016] The Néel vector in the antiferromagnetic layer changes upward or downward. When the Néel vector is upward, i.e., a positive value, the state value of the memory cell is defined as 1; when the Néel vector is downward, i.e. a negative value, the state value of the memory cell is defined as 0.

[0017] Furthermore, the magnitudes of I1 and I2 satisfy a competitive relationship: after the current exceeds the critical current for reversal, the damping torque generated by I1 flowing into the heavy metal layer and the alternating field torque generated by I2 flowing into the antiferromagnetic layer need to be balanced and cancel each other out after the antiferromagnetic moment is reversed, so as to achieve stable reversal.

[0018] The beneficial effects of the present invention are as follows: The present invention provides a vertically magnetized antiferromagnetic random access memory and its storage method that do not require external field assistance. The storage unit of the vertically magnetized antiferromagnetic random access memory has a higher magnetic moment reversal speed and better storage stability. At the same time, it has the advantages of simple structure, high speed, resistance to stray field disturbances, and non-volatility. The storage unit is especially faster in terms of read and write speed. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the vertical magnetization antiferromagnetic memory structure of the present invention that does not require external field assistance;

[0020] Figure 2 This is a front view of the magnetic storage device of the present invention;

[0021] Figure 3a This is a schematic diagram of a first current-carrying embodiment of the magnetic recording element according to the first embodiment of the present invention;

[0022] Figure 3b This is a schematic diagram of a second current-carrying embodiment of the magnetic recording element according to the first embodiment of the present invention;

[0023] Figure 4a For the purposes of this invention Figure 3a The Néel vector in the z-direction of the antiferromagnetic layer changes with time under certain conditions;

[0024] Figure 4b For the purposes of this invention Figure 3b The Néel vector in the z-direction of the antiferromagnetic layer changes with time under certain conditions;

[0025] Figure 5a This is a schematic diagram of a first current-carrying embodiment of the magnetic recording element according to the second embodiment of the present invention;

[0026] Figure 5b This is a schematic diagram of a second current implementation method for the magnetic recording element according to a second embodiment of the present invention;

[0027] Figure 6a For the purposes of this invention Figure 5a The Néel vector in the z-direction of the antiferromagnetic layer changes with time under certain conditions;

[0028] Figure 6b For the purposes of this invention Figure 5bThe graph shows the change of the Néel vector in the z-direction of the antiferromagnetic layer over time under certain conditions. Detailed Implementation

[0029] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0030] This invention relates to a vertically magnetized antiferromagnetic magnetic memory that requires no external field assistance, based on a vertically magnetized antiferromagnetic magnetic structure. For example... Figure 1 , 2 The diagram shows a schematic of a vertically magnetized antiferromagnetic random access memory structure that requires no external field assistance. This vertically magnetized antiferromagnetic random access memory has a three-layer structure (top, middle, and bottom), including an antiferromagnetic (AFM) layer 1, an insulating layer (I) 5, and a heavy metal (HM) layer 2. It also includes a first set of endpoints 3 formed by two endpoints on two non-adjacent sides of the heavy metal layer 2, and a second set of endpoints 4 formed by two endpoints on two non-adjacent sides of the antiferromagnetic layer 1. The first set of endpoints 3 is used to connect a first DC current source I1 to supply DC current to the heavy metal layer 2, and the second set of endpoints 4 is used to connect a second DC current source I2 to supply DC current to the antiferromagnetic layer 1. The lines connecting the first set of endpoints 3 and the second set of endpoints 4 are spatially perpendicular to each other. The antiferromagnetic layer 1 is a rare-earth-transition metal amorphous alloy, where the rare-earth element is one of Tb, Gd, or Ho, and the transition metal is one of Co, Fe, or Ni, or other antiferromagnetic materials with vertical anisotropy. The insulating layer (I) 5 serves as an information storage layer, acting as an insulating layer that can isolate electronic currents. However, at a specific thickness, spin-polarized currents can tunnel from the heavy metal layer 2 to the antiferromagnetic layer 1, such as NiO. The heavy metal layer 2 is a layer of heavy metal elements with a large spin Hall angle. The element is one of the non-magnetic heavy metals such as Ta, W, Pt, Au, and Ir, or a non-magnetic alloy formed by these non-magnetic heavy metals and other transition metals.

[0031] The two sets of write currents in the AFM and HM layers are spatially perpendicular, and the specific location of the current flow is not limited. The thickness of all three layers is on the order of nanometers, with the thickness of the antiferromagnetic layer 1 preferably below 3 nm. For example... Figure 2 The image shows a front view of the magnetic storage device.

[0032] Typically, when a current flows through the heavy metal layer 2, all electrons, regardless of their spin direction, move in the opposite direction to the current. The electron spin direction depends on the direction of electron motion due to the spin Hall effect, easily generating a pure spin current J. s,1This generates a damped spin-orbit torque that acts on the magnetic moment of the magnetic material. When a current is passed into the antiferromagnetic layer 1, a pure spin current J is also generated. s,2 Typically, AFM materials exhibit large spin-orbit torque. Due to the unique properties of antiferromagnetism, alternating field torques are generated, acting on the two opposite magnetic moments coupled together by the antiferromagnets.

[0033] When using this vertically magnetized antiferromagnetic random access memory (RAM) cell for data storage, the following steps are included:

[0034] 1) Connect the first set of endpoints 3 of the heavy metal layer 2 to the first DC current source I1;

[0035] 2) Connect the second set of endpoints 4 of the antiferromagnetic layer 1 to the second DC current source I2;

[0036] 3) When it is necessary to rewrite the magnetization state in the antimagnet information storage point, a direct current is simultaneously applied to the first set of endpoints 3 and the second set of endpoints 4, with a current magnitude of 1×10⁻⁶. 7 ~1×10 9 A / cm 2 ;

[0037] The magnitudes of I1 and I2 need to satisfy a certain competitive relationship. After the applied current exceeds the critical current for reversal, the damping torque generated by I1 applied to the heavy metal layer and the alternating field torque generated by I2 applied to the antiferromagnetic layer need to reach a balance after the antiferromagnetic magnetic moment is reversed, so as to cancel each other out and achieve stable reversal.

[0038] 4) The spin current generated by the DC current passed through the first set of endpoints 3 on the heavy metal layer 2 enters the antiferromagnetic layer 1 from the heavy metal layer 2. Together with the spin current generated by the DC current passed through the second set of endpoints 4 on the antiferromagnetic layer 1 in the antiferromagnetic layer 1, it causes the magnetic moment in the antiferromagnetic layer 1 to reverse.

[0039] 5) When a DC current is continuously applied and the spin Hall angle of the heavy metal layer is positive, when the direction of I1 is +x and the direction of I2 is +y, the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the +z direction; when the direction of I1 is +x and the direction of I2 is -y, the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the -z direction; when the direction of I1 is -x and the direction of I2 is +y, the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the -z direction; when the direction of I1 is -x and the direction of I2 is -y, the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the +z direction.

[0040] When the spin Hall angle of the heavy metal is negative, the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the -z direction when the direction of I1 is +x and the direction of I2 is +y; the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the +z direction when the direction of I1 is +x and the direction of I2 is -y; the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the +z direction when the direction of I1 is -x and the direction of I2 is +y; the stable state of the Néel vector in the antiferromagnetic layer 1 tends to be in the -z direction when the direction of I1 is -x and the direction of I2 is -y.

[0041] The upward or downward state of the Néel vector in antiferromagnetic layer 1 can also be distinguished by the difference in the second harmonic magnetoresistance effect. This causes the Néel vector in antiferromagnetic layer 1 to change upward or downward. When the Néel vector is upward, that is, a positive value, the state value of the memory cell is defined as 1; when the Néel vector is downward, that is, a negative value, the state value of the memory cell is defined as 0.

[0042] The writing method of this invention no longer relies entirely on the current flowing through the magnetic tunnel junction of the memory cell to flip the magnetic moment of the memory layer. Instead, a write current of a certain current density flows between the electrodes on the heavy metal layer 2 that the magnetic layer contacts and the electrodes on the magnetic layer, achieving the flipping of the memory layer through the spin-orbit torque effect. The write current applied in this method does not directly pass through the magnetic tunnel junction, therefore it has no direct impact on the breakdown probability of the magnetic tunnel junction, thus isolating the write speed and the lifespan of the magnetic memory.

[0043] Typically, the device is a three-dimensional structure with a planar layer along the xy direction and a height along the z direction of the xyz Cartesian coordinate system. The upward or downward state of the Néel vector in the antiferromagnetic layer 1 can be distinguished by the difference in the second harmonic magnetoresistance effect, thereby allowing the information stored in the antiferromagnetic memory to be read out.

[0044] First embodiment:

[0045] like Figure 1 In the coordinate system, the center of the magnetic storage is the center of the three-dimensional structure, the thickness of the upper and lower layers is in the z-direction, the direction towards the HM layer is positive, the line connecting the first set of endpoints 3 is in the x-direction, and the line connecting the second set of endpoints 4 is in the y-direction. For example... Figure 3a As shown, the spin Hall angle of the heavy metal material used at this time is positive. When a DC current I1, exceeding the critical current for magnetization reversal and within a certain range, flows from the heavy metal layer 2 towards the -x-axis, and simultaneously a matching DC current I2 flows from the antiferromagnetic layer towards the +y-axis, the Néel vector of the magnetic recording element... l The magnetization shifts to the -z direction, in which the magnetization remains stable regardless of whether current is removed or continuously injected. The Néel vector in the z-direction... lRelationships that change over time, such as Figure 4a As shown.

[0046] Furthermore, when current I1 flows from the heavy metal layer 2 towards the +x axis, and simultaneously a matching DC current I2 flows from the antiferromagnetic layer towards the +y axis, such as Figure 3b As shown. The Néel vector of the magnetic recording element becomes in the +z direction, in which the magnetization remains stable regardless of whether the current is removed or continuously injected. The Néel vector in the z direction. l Relationships that change over time, such as Figure 4b As shown.

[0047] Second embodiment:

[0048] When a DC current I1, exceeding the critical current for magnetization reversal and within a certain range, flows from the heavy metal layer 2 towards the -x axis, and simultaneously a matching DC current I2 flows from the antiferromagnetic layer towards the -y axis, such as Figure 5a As shown. The Néel vector of the magnetic recording element becomes in the +z direction, in which the magnetization remains stable regardless of whether the current is removed or continuously injected. The Néel vector in the z direction. l Relationships that change over time, such as Figure 6a As shown.

[0049] Furthermore, when current I1 flows from the heavy metal layer 2 towards the +x axis, and simultaneously a matching DC current I2 flows from the antiferromagnetic layer towards the -y axis, such as Figure 5b As shown. The Néel vector of the magnetic recording element becomes in the -z direction, in which the magnetization remains stable regardless of whether the current is removed or continuously injected. The Néel vector in the z direction. l Relationships that change over time, such as Figure 6b As shown.

[0050] In this invention, the antiferromagnetic storage unit with vertical anisotropy can control its magnetization state and complete the writing of information by means of direct current without external field assistance.

[0051] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A vertically magnetized antiferromagnetic memory that requires no external field assistance, characterized in that, It includes an antiferromagnetic layer, an insulating layer, and a heavy metal layer from top to bottom. The two sets of write currents in the antiferromagnetic layer and the heavy metal layer are perpendicular to each other in space. By controlling the magnitude and direction of the two sets of write currents in the antiferromagnetic layer and the heavy metal layer, the state of the Néel vector in the antiferromagnetic layer can be controlled to be upward or downward. The state of the Néel vector represents different stored information.

2. The vertically magnetized antiferromagnetic memory without external field assistance according to claim 1, characterized in that, The antiferromagnetic layer is made of a rare earth-transition metal amorphous alloy, wherein the rare earth element is one of Tb, Gd, or Ho, and the transition metal is an antiferromagnetic material with vertical anisotropy.

3. The vertically magnetized antiferromagnetic memory without external field assistance according to claim 1, characterized in that, The heavy metal layer is a layer of heavy metal elements with a large spin Hall angle. The element is one of the nonmagnetic heavy metals Ta, W, Pt, Au, and Ir, or a nonmagnetic alloy formed by the nonmagnetic heavy metal and other transition metals.

4. The vertically magnetized antiferromagnetic memory without external field assistance according to claim 1, 2, or 3, characterized in that, The thicknesses of the antiferromagnetic layer, insulating layer, and heavy metal layer are all in the nanometer range.

5. The vertically magnetized antiferromagnetic magnetic storage device without external field assistance according to claim 4, characterized in that, The thickness of the antiferromagnetic layer is less than 3 nm.

6. A storage method for a vertically magnetized antiferromagnetic memory that does not require external field assistance, characterized in that, Storage is performed on the vertically magnetized antiferromagnetic magnetic memory without external field assistance as described in claim 4 or 5. When current is passed through the antiferromagnetic layer of the vertically magnetized antiferromagnetic magnetic memory, an alternating field torque is generated. When current flows through the heavy metal layer of the magnetic memory, all electrons move in the opposite direction to the current. The spin direction of the electrons depends on the direction of electron motion due to the spin Hall effect, so as to generate a damped spin orbital torque acting on the magnetic moment of the magnetic material of the antiferromagnetic layer. The antiferromagnetic magnetic moment is reversed by the coupling of the two torques in the antiferromagnetic layer. When the Néel vector in the antiferromagnetic layer is upward, that is, when it is positive, the state value of the storage cell in the insulating layer is defined as 1; when the Néel vector is downward, that is, when it is negative, the state value of the storage cell is defined as 0.

7. The storage method of the vertical magnetized antiferromagnetic magnetic memory without external field assistance according to claim 6, characterized in that, The center of the vertically magnetized antiferromagnetic magnetic memory is the center of the three-dimensional structure. The thickness of the upper and lower layers is in the z-direction. The heavy metal layer is connected to the first DC current source I1, and the current flowing through the heavy metal layer is in the x-direction. The antiferromagnetic layer is connected to the second DC current source I2, and the current flowing through the antiferromagnetic layer is in the y-direction. Specifically, the process includes the following steps: A: When it is necessary to rewrite the magnetization state in the antiferromagnetic information storage point, a direct current is simultaneously applied to both the heavy metal layer and the antiferromagnetic layer, with a current magnitude of 1×10⁻⁶. 7 ~1×10 9 A / cm 2 ; B: The spin current generated by the DC current passed through the heavy metal layer enters the antiferromagnetic layer from the heavy metal layer. Together with the spin current generated by the DC current passed through the antiferromagnetic layer in the antiferromagnetic layer, it causes the magnetic moment in the antiferromagnetic layer to reverse. C: When a DC current is continuously applied and the spin Hall angle of the heavy metal layer is positive, the steady state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is +x and the direction of I2 is +y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is +x and the direction of I2 is -y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is -x and the direction of I2 is +y; the steady state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is -x and the direction of I2 is -y. When the spin Hall angle of the heavy metal is negative, the stable state of the Néel vector in the antiferromagnetic layer tends to be in the -z direction when the direction of I1 is +x and the direction of I2 is +y; the stable state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is +x and the direction of I2 is -y; the stable state of the Néel vector in the antiferromagnetic layer tends to be in the +z direction when the direction of I1 is -x and the direction of I2 is +y; the stable state of the Néel vector in antiferromagnetic layer 1 tends to be in the -z direction when the direction of I1 is -x and the direction of I2 is -y. The Néel vector in the antiferromagnetic layer changes upward or downward. When the Néel vector is upward, i.e., a positive value, the state value of the memory cell is defined as 1; when the Néel vector is downward, i.e. a negative value, the state value of the memory cell is defined as 0.

8. The storage method of the vertical magnetized antiferromagnetic magnetic memory without external field assistance according to claim 7, characterized in that, The magnitudes of I1 and I2 satisfy a competitive relationship: after the current exceeds the critical current for reversal, the damping torque generated by I1 flowing into the heavy metal layer and the alternating field torque generated by I2 flowing into the antiferromagnetic layer need to be balanced and cancel each other out after the antiferromagnetic moment is reversed, so as to achieve stable reversal.

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