CN115458002A - Vertical magnetization antiferromagnetic magnetic memory without external field assistance and storage method thereof - Google Patents
Vertical magnetization antiferromagnetic magnetic memory without external field assistance and storage method thereof Download PDFInfo
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Abstract
The invention relates to a perpendicular magnetization antiferromagnetic memory without external field assistance and a storage method thereof, which comprises an antiferromagnetic layer, an insulating layer and a heavy metal layer from top to bottom, wherein two groups of write currents of the antiferromagnetic layer and the heavy metal layer are mutually perpendicular in space, the magnitude and the direction of the two groups of write currents of the antiferromagnetic layer and the heavy metal layer are controlled, and the upward or downward state of an Neel vector in the antiferromagnetic layer can be controlled, wherein the Neel vector state represents different stored information. The N el vector of an antiferromagnetic device is regulated and controlled by using direct current, data writing is realized, the array arrangement density of the storage unit is improved, and the energy consumption is saved. The storage unit of the vertical magnetization antiferromagnetic magnetic random access memory has higher magnetic moment overturning speed, better storage stability, simple structure, high speed, stray field disturbance resistance and non-volatility, and is particularly higher in reading and writing speed.
Description
Technical Field
The invention relates to a storage technology, in particular to a vertical magnetization antiferromagnetic magnetic memory without external field assistance and a storage method thereof.
Background
Magnetic Random Access Memory (MRAM) refers to a random access memory that stores data in a magnetoresistive value or a change in a magnetization state, and records 0 and 1 using a difference in a magnetization state or a magnetoresistance value generated therefrom, and the recorded information is not changed as long as an external magnetic field or an input control current is not applied, and the magnetization state thereof is not changed. The magnetic random access memory has high-speed reading and writing capability and high integration, and provides a new method for obtaining electronic storage equipment with higher information reading and writing speed, higher data access density, lower power consumption and more portability. And because the material also has the advantages of nonvolatility, low power consumption, radiation resistance and the like, the material has important application in the computer, industrial automation, aerospace and defense industries. The main magnetic random access memories at present are magnetic field driven MRAM, and the other current driven spin transfer torque driven MRAM is called STT-MRAM for short. For the current drive type, the magnetization inversion speed using STT is fast, but the critical current density for magnetization inversion is relatively high. The power consumption of the device is increased. In recent years, another driving method, i.e. by spin-orbit torque, has been proposed based on the current-driven magnetization switching method. Since the injection of current into the heavy metal layer generates spin current perpendicular to the current direction due to spin-orbit coupling, the spin current also acts on the magnetic material in close proximity to the heavy metal layer, thereby generating spin-orbit torque to change the magnetization state of the magnetic layer, which is referred to as spin-orbit torque-driven MRAM (SOT-MRAM). In previous studies, the magnetic layer is usually made of ferromagnetic material or ferrimagnetic material due to the difficulty of switching magnetization state and the limitation of switching mechanism study.
Compared with the traditional ferromagnetic material and ferrimagnetic material, the antiferromagnetic material can bring faster information writing and more stable interference to external field because the strong coupling field between atoms and the integral net magnetic moment of the antiferromagnetic material are zero. While magnetic memory devices provide non-volatile storage under many operating conditions, there is a need for more robust data storage in such devices so that data is maintained even after the memory is exposed to adverse conditions, such as non-preset stray fields and the like.
Disclosure of Invention
Aiming at the problem of the magnetization state of a spin orbit torque driven magnetic random access memory, a perpendicular magnetization antiferromagnetic magnetic memory without external field assistance and a storage method thereof are provided, and data writing is realized by only regulating and controlling an antiferromagnetic material-based SOT-MRAM (spin on orbit magnetic random access memory) through current, namely regulating and controlling an N é el vector of an antiferromagnetic device by using direct current, so that the array density of a storage unit array is improved, and the energy consumption is saved. The magnetic moment overturning speed and the storage stability of the traditional magnetic memory are improved. The device structure can realize stable writing of data only through current without external field assistance.
The technical scheme of the invention is as follows: a perpendicular magnetization antiferromagnetic magnetic memory without external field assistance comprises an antiferromagnetic layer, an insulating layer and a heavy metal layer from top to bottom, wherein two groups of write currents of the antiferromagnetic layer and the heavy metal layer are mutually perpendicular in space, the magnitude and the direction of the two groups of write currents of the antiferromagnetic layer and the heavy metal layer are controlled, the upward or downward state of a Neel vector in the antiferromagnetic layer can be controlled, and the Neel vector state represents different stored information.
Preferably, the antiferromagnetic layer is made of a rare earth-transition group metal amorphous alloy, the rare earth element of the antiferromagnetic layer is one of Tb, gd and Ho elements, and the transition group metal is an antiferromagnetic material having perpendicular anisotropy.
Preferably, the heavy metal layer is a heavy metal element layer with a large spin hall angle, and the element of the heavy metal layer is one of non-magnetic heavy metals of Ta, W, pt, au and Ir, or a non-magnetic alloy formed by the non-magnetic heavy metal and other transition group metals.
Preferably, the thicknesses of the antiferromagnetic layer, the insulating layer and the heavy metal layer are all in the nm order.
Preferably, the thickness of the antiferromagnetic layer is 3nm or less.
A storage method of a vertical magnetization antiferromagnetic magnetic memory without external field assistance is characterized in that when current is introduced into an antiferromagnetic layer of the vertical magnetization antiferromagnetic magnetic memory, staggered field-like torque is generated; when current flows through the heavy metal layer of the magnetic memory, all electrons move in the direction opposite to the current, and the spin direction of the electrons depends on the movement direction of the electrons due to the spin Hall effect so as to generate damping spin orbit torque to act on the magnetic moment of the antiferromagnetic layer magnetic substance; the anti-ferromagnetic magnetic moment reversal is realized through two torque couplings of the anti-ferromagnetic layer, and when the Neel vector in the anti-ferromagnetic layer is upward, namely a positive value, the state value of the storage unit in the insulating layer is defined as 1; when the neel vector is downward, i.e. negative, the state value of the memory cell is defined as 0.
Further, the center of the perpendicular magnetization antiferromagnetic magnetic memory is the center of a three-dimensional structure, the thickness of the upper layer and the lower layer is the z direction, the thickness of the heavy metal layer is positive, the writing current direction of the heavy metal layer is the x direction, and the writing current direction of the antiferromagnetic layer is the y direction; the method specifically comprises the following steps:
when the magnetization state of the antiferromagnetic information storage point needs to be rewritten, direct current is simultaneously introduced into the heavy metal layer and the antiferromagnetic layer, and the magnitude of the current is 1 x 10 7 ～1×10 9 A/cm 2 ；
B: enabling the spin current generated by the direct current introduced to the heavy metal layer to enter the antiferromagnetic layer from the heavy metal layer and enabling the spin current to act together with the spin current generated by the direct current introduced to the antiferromagnetic layer in the antiferromagnetic layer to drive the magnetic moment in the antiferromagnetic layer to be reversed;
c: continuously introducing direct current, and when the spin Hall angle of the heavy metal layer is positive, when I is 1 Is in the direction of + x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be in the + z direction; when I 1 Is in the direction of + x and I 2 When the direction of (b) is-y, the steady state of the Neel vector in the antiferromagnetic layer tends to be the-z direction; when I 1 In the direction of-x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be the-z direction; when I 1 Is in the direction of-x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the + z direction;
when the spin Hall angle of the heavy metal is negative, when I 1 Is in the direction of + x and I 2 With a direction of + y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the-z direction; when I is 1 Is in the direction of + x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the + z direction; when I is 1 In the direction of-x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be in the + z direction; when I 1 Is in the direction of-x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends toward the-z direction;
the N é el vector in the antiferromagnetic layer changes upwards or downwards, and when the N é el vector is upwards, namely a positive value, the state value of the storage unit is defined as 1; when the neel vector is downward, i.e. negative, the state value of the memory cell is defined as 0.
Further, the I 1 And I 2 The size of (b) satisfies the competitive relationship: after the current is introduced to exceed the reversed critical current, introducing I of the heavy metal layer 1 Damping-like torque generated and I passed into antiferromagnetic layer 2 The generated staggered field torque needs to be balanced and offset after the anti-ferromagnetic magnetic moment is turned, so that stable turning is realized.
The invention has the beneficial effects that: the invention relates to a vertical magnetization antiferromagnetic magnetic memory without external field assistance and a storage method thereof, wherein the storage unit of the vertical magnetization antiferromagnetic magnetic random access memory has higher magnetic moment overturning speed, better storage stability, simple structure, high speed, stray field disturbance resistance and non-volatility, and the storage unit is particularly higher in reading and writing speed.
Drawings
FIG. 1 is a schematic diagram of a perpendicular magnetization antiferromagnetic memory without the assistance of an external field according to the present invention;
FIG. 2 is a front view of a magnetic memory of the present invention;
FIG. 3a is a schematic diagram of a first current implementation of the magnetic recording element of the first embodiment of the present invention;
FIG. 3b is a schematic diagram of a second current implementation of the magnetic recording element of the first embodiment of the present invention;
FIG. 4a is a graph showing the z-direction Neel vector of the antiferromagnetic layer of FIG. 3a as a function of time under conditions in accordance with the present invention;
FIG. 4b is a graph showing the z-direction Neel vector of the antiferromagnetic layer of FIG. 3b as a function of time under conditions in accordance with the present invention;
FIG. 5a is a schematic diagram of a first current implementation of a magnetic recording element in accordance with a second embodiment of the present invention;
FIG. 5b is a schematic diagram of a second current implementation of a magnetic recording element in accordance with a second embodiment of the present invention;
FIG. 6a is a graph showing the z-direction Neel vector of the antiferromagnetic layer of FIG. 5a as a function of time under conditions in accordance with the present invention;
FIG. 6b is a graph showing the change of the Neel vector in the z-direction of the antiferromagnetic layer of FIG. 5b over time under the influence of conditions.
Detailed Description
The invention is described in detail below with reference to the figures and the specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.
The invention relates to a vertical magnetization antiferromagnetic magnetic memory without external field assistance, which is based on a vertical magnetization antiferromagnetic magnetic structure. As shown in FIG. 1 and FIG. 2, a schematic diagram of a perpendicular magnetization antiferromagnetic magnetic random access memory without external field assistance, which is a vertical magnetization antiferromagnetic magnetic random access memory having a memory cell with three layers, including an Antiferromagnetic (AFM) layer 1, an insulating layer (I) 5, a Heavy Metal (HM) layer 2, a first set of terminals 3 formed by two terminals on two sides of the heavy metal layer 2 that are not adjacent to each other, and a second set of terminals 4 formed by two terminals on two sides of the antiferromagnetic layer 1 that are not adjacent to each other, where the first set of terminals 3 is used for connecting a first DC current source I 1 A direct current is introduced into the heavy metal layer 2, and the second group of endpoints 4 are used for being connected with a second direct current source I 2 A direct current is applied to the antiferromagnetic layer 1. The connecting line of the first group of the end points 3 and the connecting line of the second group of the end points 4 are arranged perpendicular to each other. The antiferromagnetic layer 1 is a rare earth-transition metalThe amorphous alloy has one of Tb, gd and Ho as rare earth element and one of Co, fe and Ni as transition metal or other antiferromagnet material with vertical anisotropy. The insulating layer (I) 5 serves as an information storage layer, and is an insulator layer that can isolate an electron current, but a spin-polarized current can tunnel from the heavy metal layer 2 to the antiferromagnetic layer 1 at a specific thickness, such as NiO. The heavy metal layer 2 is a heavy metal element layer with a large spin hall angle, and the element of the heavy metal layer is one of nonmagnetic heavy metals such as Ta, W, pt, au, ir and the like, or a nonmagnetic alloy formed by the nonmagnetic heavy metals and other transition group metals.
The two groups of write currents of the AFM layer and the HM layer are mutually vertical in space, and the specific position of the current is not limited. The thickness of the three-layer structure is nm, and the thickness of the antiferromagnetic layer 1 is preferably 3nm or less. As shown in the front view of the magnetic memory of fig. 2.
In general, when a current flows through the heavy metal layer 2, all electrons move in the direction opposite to the current regardless of the spin direction. The spin direction of the electron depends on the electron movement direction due to the spin Hall effect, and the pure spin current J is easy to generate s,1 So as to generate a damping-like spin orbit torque to act on the magnetic moment of the magnetic substance. When a current is applied to the antiferromagnetic layer 1, a pure spin current J is also generated s,2 Generally, AFM materials have a large spin-orbit torque. Due to the special properties of antiferromagnetism, an interleaved field-like torque is generated, acting on two opposite magnetic moments of the antiferromagnetically coupling, respectively.
When the memory cell of the vertical magnetization antiferromagnetic magnetic random access memory is used for data storage, the method comprises the following steps:
1) Connecting the first group of terminals 3 of the heavy metal layer 2 with a first direct current source I 1 Connecting;
2) Connecting the second set of terminals 4 of the antiferromagnetic layer 1 with a second DC current source I 2 Connecting;
3) When the magnetization state in the diamagnetic information storage point needs to be rewritten, direct current is simultaneously introduced into the first group of terminals 3 and the second group of terminals 4, and the current is 1 multiplied by 10 7 ～1×10 9 A/cm 2 ；
I 1 And I 2 The size of (a) needs to satisfy a certain competitive relationship. After the current is introduced to exceed the reversed critical current, introducing I of the heavy metal layer 1 Damping-like torque generated and I passed into the antiferromagnetic layer 2 The generated staggered field torque needs to be balanced and offset after the anti-ferromagnetic magnetic moment is turned, so that stable turning is realized.
4) The spin current generated by the direct current introduced into the first group of terminals 3 on the heavy metal layer 2 enters the antiferromagnetic layer 1 from the heavy metal layer 2, and interacts with the spin current generated in the antiferromagnetic layer 1 by the direct current introduced into the second group of terminals 4 on the antiferromagnetic layer 1 to flip the magnetic moment in the antiferromagnetic layer 1.
5) Continuously introducing direct current, and when the spin Hall angle of the heavy metal layer is positive, when I is 1 Is in the direction of + x and I 2 Is + y, the steady state of the neel vector in the antiferromagnetic layer 1 tends to be + z direction; when I 1 Is in the direction of + x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends toward the-z direction; when I is 1 Is in the direction of-x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends to be the-z direction; when I is 1 In the direction of-x and I 2 Is-y, the steady state of the neel vector in the antiferromagnetic layer 1 tends to be + z direction.
When the spin Hall angle of the heavy metal is negative, when I 1 Is in the direction of + x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends to be the-z direction; when I is 1 Is in the direction of + x and I 2 With the direction of-y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends to be in the + z direction; when I is 1 Is in the direction of-x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends to be in the + z direction; when I is 1 Is in the direction of-x and I 2 Is-y, the steady state of the N é el vector in the antiferromagnetic layer 1 tends toward the-z direction.
The upward or downward state of the neel vector in the antiferromagnetic layer 1 can also be distinguished by the difference in the second harmonic magnetoresistance effect. Thus, the neel vector in the antiferromagnetic layer 1 is changed upwards or downwards, and when the neel vector is upwards, namely a positive value, the state value of the memory cell is defined as 1; when the neel vector is downward, i.e. negative, the state value of the memory cell is defined as 0.
The writing method does not depend on the magnetic moment of the memory layer to be turned over by current in the magnetic tunnel junction of the memory unit, but realizes the turning over of the memory layer by the spin-orbit torque effect by passing writing current with certain current density in the electrode on the heavy metal layer 2 and the electrode on the magnetic layer which are contacted with the magnetic layer. The writing current applied by the method does not directly pass through the magnetic tunnel junction, so that the breakdown probability of the magnetic tunnel junction is not directly influenced, and two factors of the writing speed and the service life of the magnetic memory are independent.
In general, a device is a three-dimensional structure having planar layers along the x-y direction and a height along the z-direction of an x-y-z Cartesian coordinate system.
The upward or downward state of the neel vector in the antiferromagnetic layer 1 can be distinguished by the difference in the second harmonic magnetoresistance effect, and the information stored in the antiferromagnetic memory can be read out.
(1) First embodiment
As shown in FIG. 1, the center of the magnetic memory is the center of the three-dimensional structure, the thickness of the upper and lower layers is in the z direction, the thickness is positive toward the HM layer, the connecting line of the first group of endpoints 3 is in the x direction, and the connecting line of the second group of endpoints 4 is in the y direction. As shown in fig. 3a, the spin hall angle of the heavy metal material used at this time is positive. Direct current I within a certain range when the current is higher than the critical current of magnetization reversal 1 Flows from the heavy metal layer 2 in the-x-axis direction and simultaneously has a DC current I of a magnitude matched with that of the heavy metal layer 2 When flowing from the antiferromagnetic layer in the + y-axis direction, the Neel vector l of the magnetic recording element changes to the-z direction, and in this state, the magnetization state remains stable regardless of removal or continued injection of current. The z-direction neel vector l varies with time as shown in fig. 4 a.
When the current I is larger than the predetermined value 1 From the heavy metal layer 2 towardsA direct current I flowing in the + x-axis direction and having a magnitude matching therewith 2 When flowing from the antiferromagnetic layer in the + y direction, as shown in fig. 3 b. The neel vector of the magnetic recording element becomes the + z direction, in which state the magnetization state remains stable regardless of the removal or continued injection of current. The z-direction neel vector l varies with time as shown in fig. 4 b.
Second embodiment
Direct current I within a certain range when the current is higher than the critical current of magnetization reversal 1 Flows from the heavy metal layer 2 in the-x-axis direction and simultaneously has a DC current I of a magnitude matched with that of the heavy metal layer 2 When flowing from the antiferromagnetic layer in the-y direction as shown in fig. 5 a. The neel vector of the magnetic recording element becomes the + z direction, in which state the magnetization state remains stable regardless of the removal or continued injection of current. The z-direction neel vector l varies with time as shown in fig. 6 a.
When the current I is larger than the predetermined value 1 Flows from the heavy metal layer 2 in the + x-axis direction and has a DC current I of a magnitude matching the same 2 When flowing from the antiferromagnetic layer in the-y direction, as shown in fig. 5 b. The neel vector of the magnetic recording element becomes the-z direction, in which state the magnetization state remains stable, regardless of the removal or continued injection of current. The z-direction neel vector l varies with time as shown in fig. 6 b.
The antiferromagnetic storage unit with the vertical anisotropy can regulate the magnetization state of the antiferromagnetic storage unit through direct current under the condition of no external field assistance so as to complete the writing of information.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (8)
1. A perpendicular magnetization antiferromagnetic magnetic memory without external field assistance is characterized by comprising an antiferromagnetic layer, an insulating layer and a heavy metal layer from top to bottom, wherein two groups of writing currents of the antiferromagnetic layer and the heavy metal layer are mutually perpendicular in space, the magnitude and the direction of the two groups of writing currents of the antiferromagnetic layer and the heavy metal layer are controlled, the upward or downward state of an Neel vector in the antiferromagnetic layer can be controlled, and the Neel vector state represents different stored information.
2. The perpendicular magnetization antiferromagnetic memory according to claim 1, wherein the antiferromagnetic layer is made of an amorphous alloy of rare earth-transition metal, the rare earth element is one of Tb, gd and Ho, and the transition metal is made of an antiferromagnetic material with perpendicular anisotropy.
3. The perpendicular magnetization antiferromagnetic magnetic memory according to claim 1, wherein the heavy metal layer is a heavy metal element layer with a large spin hall angle, the element is one of the nonmagnetic heavy metals Ta, W, pt, au, ir, or the nonmagnetic alloy of the nonmagnetic heavy metal and other transition group metals.
4. A perpendicular magnetization antiferromagnetic memory without external field assist as recited in claim 1, 2 or 3, wherein the thicknesses of the antiferromagnetic layer, the insulating layer and the heavy metal layer are nm order.
5. A perpendicular magnetized antiferromagnetic magnetic memory without external field assist as recited in claim 4, wherein the antiferromagnetic layer is below 3nm thick.
6. A storage method of a vertical magnetization antiferromagnetic magnetic memory without external field assistance is characterized in that when current is introduced into an antiferromagnetic layer of the vertical magnetization antiferromagnetic magnetic memory, staggered field-like torque is generated; when current flows through the heavy metal layer of the magnetic memory, all electrons move in the direction opposite to the current, and the spin direction of the electrons depends on the movement direction of the electrons due to the spin Hall effect so as to generate damping spin orbit torque to act on the magnetic moment of the magnetic substance of the antiferromagnetic layer; the anti-ferromagnetic magnetic moment reversal is realized through two torque couplings of the anti-ferromagnetic layer, and when the Neel vector in the anti-ferromagnetic layer is upward, namely a positive value, the state value of the storage unit in the insulating layer is defined as 1; when the neel vector is downward, i.e. negative, the state value of the memory cell is defined as 0.
7. The storage method of a vertical magnetization antiferromagnetic magnetic memory without external field assistance as claimed in claim 6, wherein the center of the vertical magnetization antiferromagnetic magnetic memory is the center of a three-dimensional structure, the thickness of the upper and lower layers is z direction, the thickness of the heavy metal layer is positive, the direction of the write current to the heavy metal layer is x direction, and the direction of the write current to the antiferromagnetic layer is y direction; the method specifically comprises the following steps:
when the magnetization state in the antiferromagnetic information storage point needs to be rewritten, DC current is simultaneously applied to the heavy metal layer and the antiferromagnetic layer, and the current is 1X 10 7 ～1×10 9 A/cm 2 ；
B: the self-spin current generated by the direct current introduced to the heavy metal layer enters the antiferromagnetic layer from the heavy metal layer and interacts with the self-spin current generated in the antiferromagnetic layer by the direct current introduced to the antiferromagnetic layer to drive the magnetic moment in the antiferromagnetic layer to be reversed;
c: continuously introducing direct current, and when the spin Hall angle of the heavy metal layer is positive, when I is 1 Is in the direction of + x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be in the + z direction; when I is 1 Is in the direction of + x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the-z direction; when I is 1 Is in the direction of-x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be the-z direction; when I is 1 Is in the direction of-x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the + z direction;
in useWhen the spin Hall angle of heavy metal is negative, when I 1 Is in the direction of + x and I 2 When the direction of (b) is + y, the steady state of the Neel vector in the antiferromagnetic layer tends to be the-z direction; when I is 1 Is in the direction of + x and I 2 With a direction of-y, the steady state of the Neel vector in the antiferromagnetic layer tends toward the + z direction; when I is 1 Is in the direction of-x and I 2 Is + y, the steady state of the neel vector in the antiferromagnetic layer tends towards the + z direction; when I 1 Is in the direction of-x and I 2 When the direction of (b) is-y, the steady state of the Neel vector in the antiferromagnetic layer 1 tends to be the-z direction;
the neel vector in the antiferromagnetic layer changes upwards or downwards, and when the neel vector is upwards, namely a positive value, the state value of the memory cell is defined as 1; when the neel vector is downward, i.e. negative, the state value of the memory cell is defined as 0.
8. The method for storing perpendicular magnetization antiferromagnetic memory without external field assist of claim 7, wherein I is 1 And I 2 The size of (b) satisfies the competitive relationship: after the current is introduced to exceed the reversed critical current, introducing I of the heavy metal layer 1 Damping-like torque generated and I passed into the antiferromagnetic layer 2 The generated staggered field torque needs to be balanced and offset after the antiferromagnetic magnetic moment is turned over, so that stable turning is realized.
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2022
- 2022-08-03 CN CN202210930415.3A patent/CN115458002A/en active Pending
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