CN116507131A - Memory based on magnetic substream effect - Google Patents

Abstract

The invention provides a memory based on the magnon current effect, which belongs to the field of memory, and includes a substrate, a topological insulator unit, a magnon junction unit and a bulk acoustic wave excitation unit; wherein the magnon junction unit includes from bottom to top: the first Ferromagnetic insulator layer, antiferromagnetic layer, second ferromagnetic insulator layer and heavy metal layer; bulk acoustic wave excitation unit is used to provide bulk acoustic wave excitation to the magneton junction unit to excite magnetons by means of phonon-magnon interactions The magnon flow in the junction unit, the heavy metal layer in the magnon junction unit can embody the magnon flow in the form of an inverse spin Hall effect voltage, and the topological insulator changes the magnetic moment arrangement of the first ferromagnetic insulator layer in the magnon junction unit Direction, and then adjust the magnitude of the magnetic flow in the magnetic sub-junction unit, so as to realize the high level and low level of the magnetic sub-junction unit. The invention utilizes the topological insulator to flip the magnetic moment of the magneton junction unit, and drives the magneton junction with bulk acoustic wave excitation, which is a novel storage device structure.

Description

A kind of memory based on magnon current effect

technical field

The invention belongs to the field of memory, and more specifically relates to a memory based on the magnon current effect.

Background technique

5G communication facilities are the network infrastructure that realizes the interconnection of humans, machines and things. The requirements of 5G communication include a peak rate of 10Gbps, a spectrum efficiency that is three times higher than that of IMT-A, a mobility of 500 km/h, and a delay as low as 1 millisecond. The experience data rate reaches 100Mbps, the connection density reaches 10 ⁶ per square kilometer, the energy efficiency is 100 times higher than that of IMT-A, and the traffic density reaches 10Mbps per square kilometer. Today, with the increasing popularity of 5G communication, the research and development of 6G technology has been put on the agenda. With such a huge amount of data, it poses new challenges to fast and stable storage and data processing technology. According to information storage media and methods, there are three main storage technologies at present, namely semiconductor storage, magnetic storage and optical storage. Among them, compared with the other two technologies, magnetic storage technology has the advantages of high data storage density and non-volatility, and is one of the storage technologies that are widely concerned at present.

Spin valves based on giant magnetoresistance (Giant Magneto Resistance, GMR) and tunneling magnetoresistance (Tunnel Magneto Resistance, TMR) are currently mainstream magnetic memory structures. The success of the spin valve is that compared with traditional electronic devices, more electron spin properties are used, but it cannot get rid of the shortcomings of high power consumption and heat generation of electronic devices. The transmission of spin properties can be independent of the movement of electrons. In order to further reduce the energy loss caused by charge movement, magneton junctions are proposed. The main structure of the magnon junction uses insulator materials, and heavy metals are required to characterize the magnitude of the magnon flow, which greatly reduces the thermal effect and energy loss caused by electron transmission. By changing the orientation of the relative magnetization direction of the two magnetic insulating layers to regulate the internal The magnitude of the magnon current. The spin valves based on the GMR and TMR effects reflect the switching state through the change of resistance value, while the magnon junction based on the magnon flow is mainly characterized by the voltage change of the inverse spin Hall effect.

The use of spin-orbit torque (Spin Orbit Torque, SOT) to flip the magnetic moment is to use the current flowing in the material adjacent to the ferromagnetic layer. The spin polarization at λ generates a net spin current, which transfers angular momentum to the ferromagnetic layer, thereby flipping the magnetic moment of the ferromagnetic layer. Patent document CN109585644A proposes a magnetoresistive tunnel junction provided on the spin-orbit torque coupling layer. There is a temperature difference with the other side, and under the action of the temperature difference, the directional flip of the SOT-MRAM magnetic moment is realized. At present, the excitation mode of the magnon flow in the magnon junction is temperature gradient excitation. The temperature gradient excitation means that when there is a temperature difference in the magnet, the magnon flow will be generated in the magnet along the direction of the temperature gradient. The use of temperature difference for magnetic moment reversal or as a power source for the magnetic subjunction is likely to cause heating of the device and increase energy loss. The bulk acoustic wave (Bulk Acoustic Wave, BAW) can also perform magnon current excitation with high efficiency and energy saving, replacing the temperature gradient excitation as the power source of the magnon junction.

Contents of the invention

Aiming at the defects of the prior art, the purpose of the present invention is to provide a memory based on the magnon current effect, which aims to solve the problem of high power consumption and heat generation in the existing memories based on the spin valve structure and the temperature difference magnon junction. The problem.

To achieve the above object, the present invention provides a memory based on the magnon current effect, comprising: a topological insulator unit, a magnon junction unit and a bulk acoustic wave excitation unit; a topological insulator unit, a magnon junction unit and a bulk acoustic wave excitation unit on the substrate from bottom to top;

The topological insulator unit includes a topological insulator layer and an electrode layer; the electrode layer is an electrode that passes current through the topological insulator layer; the topological insulator layer is used to flip the adjacent ferromagnetic layer by spin-orbit torque when the current is passed through;

The magnetic sub-junction unit includes a first ferromagnetic insulator layer, an antiferromagnetic insulator layer, a second ferromagnetic insulator layer and a heavy metal layer from bottom to top; The direction of the magnetic moment is changed under the action; the magnetic moment of the second ferromagnetic insulator layer remains unchanged; the heavy metal layer is used to transfer the magnon current transmitted in the second ferromagnetic insulator layer to the inverse spin Hall effect voltage of the magnon junction Form expression; antiferromagnetic insulator layer is used to separate the first ferromagnetic insulator layer and the second ferromagnetic insulator layer;

The bulk acoustic wave excitation unit includes a first metal electrode layer, a piezoelectric layer and a second metal electrode layer from bottom to top; the first metal electrode layer and the second metal electrode layer are electrodes that can apply an alternating voltage, and the piezoelectric layer Used to generate bulk acoustic waves under alternating voltage, the bulk acoustic waves propagate downwards, and excite magnon currents in the magnon junction unit;

Among them, when the first ferromagnetic insulator layer and the second ferromagnetic insulator layer have the same magnetic moment direction, the inverse spin Hall voltage of the magnon junction under the action of bulk acoustic wave excitation is high, and the topological insulator After the magnetic moment of the first ferromagnetic insulator layer is reversed, stop feeding the current to the topological insulator layer. At this time, the inverse spin Hall voltage of the magnon junction is low under the action of bulk acoustic wave excitation; When the first ferromagnetic insulator layer and the second ferromagnetic insulator layer have opposite magnetic moment directions, under the action of bulk acoustic wave excitation, the inverse spin Hall voltage of the magnon junction changes from low to low before and after the current is applied to the topological insulator layer. level transitions to a high level.

Further preferably, the topological insulator layer is grown on the substrate by magnetron sputtering or molecular beam epitaxy, and the electrodes arranged above the topological insulator layer are grown by magnetron sputtering, electron beam evaporation coating or thermal evaporation coating.

Further preferably, the topological insulator layer is Bi _x Sb _1-x , Bi ₂ Se ₃ , Sb ₂ Te ₃ or Bi ₂ Te ₃ ; the electrode is Al, Cr, Cu, Mo or Ag; wherein, 0<x<1;

Further preferably, the first ferromagnetic insulator layer and the second ferromagnetic insulator layer are Y ₃ Fe ₅ O ₁₂ , CoFe ₂ O ₄ or NiFe ₂ O ₄ ; the antiferromagnetic insulator layer is NiO, Fe ₂ O ₃ , Cr ₂ O ₃ , MgO, MnO, FeO, CoO, BiFeO ₃ , LaMnO ₃ , La ₂ CuO ₄ , TmFeO 3 , ZnCr ₂ O ₄ , F ₂ , CuCl ₂ , FeCl ₂ , MnF ₂ , FeF _{2 or} KNiF ₃ ; heavy metal layer V, Cr, Cu, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Ir, Pt or Au.

Further preferably, the heavy metal layer is deposited by magnetron sputtering coating method, thermal evaporation coating method or electron beam evaporation coating method, and then patterned by photolithography.

Further preferably, the first metal electrode layer and the second metal electrode layer are deposited and prepared by magnetron sputtering coating method, thermal evaporation coating method or electron beam evaporation coating method; the piezoelectric layer is deposited by magnetron sputtering method, and then the Engraved pattern preparation.

Further preferably, the first metal electrode layer and the second metal electrode layer are V, Cr Cu, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Ir, Pt or Au; the piezoelectric layer It is PZT, AlN or PVDF.

Further preferably, the thickness of the substrate is 500 μm, the thickness of the topological insulator layer is 5 nm˜15 nm; the thickness of the electrode is 20 nm˜50 nm.

Further preferably, the thickness of the first ferromagnetic insulator layer is 20nm-30nm, the thickness of the antiferromagnetic insulating layer is 5nm-20nm; the thickness of the second ferromagnetic insulator layer is 40nm-50nm; the thickness of the heavy metal layer is 5nm-20nm.

Further preferably, the thickness of the first metal electrode layer is 20nm-100nm; the thickness of the second metal electrode layer is 20nm-100nm; the thickness of the piezoelectric layer is 20nm-100nm.

Generally speaking, compared with the prior art, the above technical solution conceived by the present invention has the following

Beneficial effect:

The present invention provides a memory based on the magnon flow effect, including a topological insulator unit, a magnon junction unit and a bulk acoustic wave excitation unit, wherein, on the one hand, the bulk acoustic wave excitation unit includes a first metal electrode layer, a piezoelectric layer and the second metal electrode layer, an alternating voltage is applied on the first metal electrode layer and the second metal electrode layer, the piezoelectric layer generates a bulk acoustic wave, and the bulk acoustic wave is transmitted downward to generate a magneton flow in the magneton junction unit , using bulk acoustic wave excitation as the power of the magnon-junction unit, using the bulk acoustic wave to excite the magnon-junction can effectively solve the heating problem of the memory and reduce the energy loss of the memory; the topological insulator unit includes a topological insulator layer and an electrode layer; on the other hand, The topological insulator layer is used to flip the magnetic moment direction of the first ferromagnetic insulator layer by using the spin-orbit torque when the current is applied, which can greatly improve the magnetic moment reversal efficiency; the present invention provides a high-efficiency, low-power consumption A new type of memory based on the magnon current effect.

Description of drawings

Fig. 1 is a schematic diagram of the separation structure of each layer of SOT-magnetic subjunction-BAW provided by the embodiment of the present invention;

Fig. 2 is a schematic diagram of a topological insulator unit used in an embodiment of the present invention;

Fig. 3 is a schematic diagram of a magnetic sub-junction unit provided by an embodiment of the present invention;

4 is a schematic diagram of the same magnetic moment direction in the initial state of the first ferromagnetic insulator layer and the second ferromagnetic insulator layer provided by the embodiment of the present invention;

Fig. 5 is a schematic diagram of the magnetic moment direction of the first ferromagnetic insulator layer and the second ferromagnetic insulator layer after the current is passed through the topological insulator layer 2 provided by the embodiment of the present invention;

Fig. 6 is a schematic diagram of a bulk acoustic wave excitation unit provided by an embodiment of the present invention;

7 is a schematic diagram of the inverse spin Hall voltage under the condition that the magnetic moment directions of the two ferromagnetic insulator layers are different according to the embodiment of the present invention;

Throughout the drawings, the same reference numerals are used to designate the same elements or structures, wherein:

1-substrate, 2-topological insulator layer, 3-electrode layer, 4-first ferromagnetic insulator layer; 5-antiferromagnetic insulator layer; 6-second ferromagnetic insulator layer; 7-heavy metal layer; 8-th Two metal electrode layers; 9-piezoelectric layer; 10-first metal electrode layer.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

In view of the above defects or improvement needs of the prior art, the object of the present invention is to provide a memory based on the magnon current effect, which uses a topological insulator to adjust the magnetic moment direction of the first ferromagnetic insulating layer of the magnon junction unit, and adopts bulk acoustic wave The power source of the excitation unit realizes high-efficiency and energy-saving storage devices.

Among them, the topological insulator has a larger spin Hall angle (Spin Hall Angle), the larger the spin Hall angle, the more polarized spin currents accumulated at the interface at the same current density, and the more conducive to flipping the magnetic moment , while using the phonon-magnon interaction, the method of injecting bulk acoustic waves into the magnon junction to excite the magnon flow can further reduce the heating and energy loss of the device.

The present invention provides a kind of memory of SOT-magnon junction-BAW, comprising: substrate, topological insulator unit located on the substrate from bottom to top, magneton junction unit and bulk acoustic wave excitation unit, wherein, bulk acoustic wave As the power source of the magneton junction, the current is passed through the topological insulator to adjust the orientation of the magnetic moment of the first ferromagnetic insulator layer of the magneton junction, and then adjust the inverse spin Hall effect voltage of the magneton junction to achieve the purpose of data storage; based on topology The bulk acoustic wave excited magnon junction structure in which the insulator regulates the magnetic moment is referred to as: SOT-magnon-junction-BAW or SOT-magnon-junction-BAW device;

Further preferably, the substrate includes but is not limited to a silicon substrate;

The topological insulator layer is grown on the substrate by magnetron sputtering or molecular beam epitaxy. When the topological insulator layer is fed with current, the magnetic moment of the first ferromagnetic insulator layer is reversed under the action of spin-orbit torque;

Further preferably, the topological insulator layer is an alloy compound material, specifically including but not limited to Bi _x Sb _1-x , Bi ₂ Se ₃ , Sb ₂ Te ₃ or Bi ₂ Te ₃ ; wherein, 0<x<1;

An electrode is arranged above the topological insulator layer, and the electrode is grown on the topological insulator layer by magnetron sputtering, electron beam evaporation coating or thermal evaporation coating, specifically including but not limited to Al, Cr, Cu, Mo or Ag;

The magnetic sub-junction unit comprises a first ferromagnetic insulator layer, an antiferromagnetic insulator layer, a second ferromagnetic insulator layer and a heavy metal layer located on the topological insulator layer from bottom to top; the first ferromagnetic insulator contained in the magnetic sub-junction unit The layer magnetic moment orientation can be adjusted by the adjacent topological insulator layer, while the second ferromagnetic insulator layer maintains the same magnetic moment orientation, so as to construct the same or opposite magnetic moment orientation of the first ferromagnetic insulator layer and the second ferromagnetic insulator layer ;

Further preferably, both the first ferromagnetic insulator layer and the second ferromagnetic insulator layer include but are not limited to Y ₃ Fe ₅ O ₁₂ , CoFe ₂ O ₄ and NiFe ₂ O ₄ layers;

Further preferably, the antiferromagnetic insulator layer is an oxide-containing compound material or a halogen-containing compound material, specifically including but not limited to NiO, Fe ₂ O ₃ , Cr ₂ O ₃ , MgO, MnO, FeO, CoO, BiFeO ₃ , LaMnO _3. La ₂ CuO ₄ , TmFeO ₃ , ZnCr ₂ O ₄ , F ₂ , CuCl ₂ , FeCl ₂ , MnF ₂ , FeF ₂ and KNiF ₃ ;

Further preferably, the heavy metal layer specifically includes but is not limited to V, Cr, Cu, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Ir, Pt or Au;

The heavy metal layer in the magneton junction is deposited by magnetron sputtering coating, thermal evaporation coating or electron beam evaporation coating, etc., and then patterned by photolithography to test the inverse spin Hall effect and characterize the high and low voltage of the magneton junction. flat;

The bulk acoustic wave excitation unit includes a first metal layer, a piezoelectric layer and a second metal layer from bottom to top; applying an alternating voltage to the first metal layer and the second metal layer will then generate an acoustic body in the piezoelectric layer wave, and the bulk acoustic wave is transmitted to the magneton junction below;

The metal layer in the bulk acoustic wave excitation unit is deposited by magnetron sputtering coating, thermal evaporation coating or electron beam evaporation coating, etc. The piezoelectric layer will be deposited by magnetron sputtering, and then patterned by photolithography;

Further preferably, the metal layer in the bulk acoustic wave excitation unit specifically includes but is not limited to V, Cr Cu, Nb, Mo, Ru, Rh, Pd, Ag, Hf, Ta, W, Re, Ir, Pt or Au; The layers are piezoelectric materials including, but not limited to, PZT, AlN or PVDF.

Example

As shown in Figure 1, the memory in the present invention includes: a bulk acoustic wave excitation unit, a magneton junction unit and a topological insulator unit;

The topological insulator unit comprises a topological insulator layer 2 and an electrode layer 3;

The topological insulator layer 2 located above the bottom substrate 1; the material design of the topological insulator layer 2 can ensure that it has a large spin Hall angle while achieving high electrical conductivity and more effective magneton junction units The magnetic moment of the first ferromagnetic insulator layer 4 in the topological insulator layer 4 is reversed; when a current is applied to the topological insulator layer 2, the current will generate a spin-orbit torque for the magnetic moment of the first ferromagnetic insulator layer 4 in the adjacent magneton junction unit , under the action of the spin-orbit torque, the magnetic moment will be reversed accordingly, the substrate 1 is a silicon substrate; the topological insulator layer 2 is specifically Bi _x Sb _1-x , in some examples, the topological insulator layer 2 is also Can be Bi ₂ Se ₃ , Sb ₂ Te ₃ or Bi ₂ Te ₃ etc.;

The specific thickness of the substrate 1 is 500 μm; the specific thickness of the topological insulator layer 2 is 10 nm, and in some examples, the thickness of the topological insulator layer can also be 5 nm to 15 nm;

The specific thickness of the electrode 3 is 30nm. In some examples, the thickness of the topological insulator layer can also be 20nm-50nm;

The magnetic sub-junction unit includes a first ferromagnetic insulator layer 4, an antiferromagnetic insulator layer 5, a second ferromagnetic insulator layer 6 and a heavy metal layer 7; the uppermost heavy metal layer 7 can transmit the second ferromagnetic insulator layer 6 to The magnon flow of the magnon is expressed in the form of the inverse spin Hall effect voltage, and the orientation of the magnetic moment of the first ferromagnetic insulator layer 4 is adjusted through the topological insulator layer 2, and the whole device can be adjusted in the state of high and low inverse spin Hall voltage ;

The first ferromagnetic insulator layer 4 and the second ferromagnetic insulator layer 6 can be Y ₃ Fe ₅ O ₁₂ , CoFe ₂ O ₄ and NiFe ₂ O ₄ ; the antiferromagnetic insulator layer 5 is an oxygen-containing compound material or a halogen compound material, Specifically including but not limited to NiO, Fe ₂ O ₃ , Cr ₂ O ₃ , MgO, MnO, FeO, CoO, BiFeO ₃ , LaMnO ₃ , La ₂ CuO ₄ , TmFeO ₃ , ZnCr ₂ O ₄ , F ₂ , CuCl ₂ , FeCl ₂ , MnF ₂ , FeF ₂ and KNiF ₃ ;

The specific thickness of the first ferromagnetic insulator layer 4 is 20 nm. In some examples, the thickness of the first ferromagnetic insulator layer 4 may be 20 nm˜30 nm, and the thickness of the antiferromagnetic insulating layer 5 is 10 nm. In some examples, the thickness of the antiferromagnetic insulator layer can also be 5nm-20nm; the specific thickness of the second ferromagnetic insulator layer 6 is 40nm; in some examples, the thickness of the second ferromagnetic insulator layer 6 can also be 40nm-50nm; Each layer in the magneton junction unit is sequentially deposited by magnetron sputtering; in some examples, each layer of the magneton junction can also be deposited by pulsed laser deposition (PLD), molecular beam epitaxy (MBE) and other methods;

The specific thickness of the heavy metal layer 7 is 10nm; in some examples, the thickness of the heavy metal layer 7 can also be 5nm～20nm; the heavy metal layer 7 is deposited on the surface of the second ferromagnetic insulator layer 6 by magnetron sputtering; in some examples, the heavy metal layer 7 can also be deposited by electron beam evaporation (E-beam), thermal evaporation and other methods;

The specific thickness of the second metal electrode layer 8 is 50 nm. In some examples, the second metal electrode layer 8 can also be 20nm-100nm; the second metal electrode layer 8 is deposited on the surface of the second ferromagnetic insulator layer 7 by magnetron sputtering; in some examples, the second metal electrode layer Layer 8 can also be deposited by methods such as electron beam evaporation (E-beam) and thermal evaporation;

The specific thickness of the piezoelectric layer 9 is 50 nm. In some examples, the thickness of the piezoelectric layer can be 20 nm to 100 nm; the material of the piezoelectric layer 9 is deposited on the surface of the second metal electrode layer 8 by magnetron sputtering;

The specific thickness of the first metal electrode layer 10 is 50nm. In some examples, the thickness of the first metal electrode layer 10 can also be 20nm-100nm; the first metal electrode layer 10 is deposited on the surface of the piezoelectric layer 9 by magnetron sputtering. In some examples, the first metal electrode layer 10 can also be deposited by methods such as electron beam evaporation (E-beam) and thermal evaporation;

The preparation method of the memory of the SOT-magnetic junction-BAW provided by the present invention comprises the following steps:

A layer of Bi _x Sb _1-x is prepared on the silicon substrate 1 by magnetron sputtering, and the corresponding element ratio is controlled by controlling the power difference between the Bi target and the Sb target sputtering source;

The first ferromagnetic insulator layer, the antiferromagnetic insulating layer, the second ferromagnetic insulator layer and the heavy metal layer are sequentially prepared by magnetron sputtering on the grown topological insulator layer;

The second metal electrode layer, the piezoelectric layer and the first metal electrode layer are sequentially prepared on the second ferromagnetic insulating layer by using a magnetron sputtering method.

Fig. 2 is a topological insulator unit, and the topological insulator layer material Bi _x Sb _1-x and electrode layer 3 of different thicknesses are grown sequentially on a silicon substrate by magnetron sputtering;

Fig. 3 is a magnon junction unit, the magnitude of the magnon flow in the magnon junction unit is measured through the heavy metal layer 7 on the second ferromagnetic insulator layer 6;

The principle of magnon junction effect is shown in Figure 1. From top to bottom, there are bulk acoustic wave excitation unit, magnon junction unit, topological insulator unit and substrate; wherein, the bulk acoustic wave excitation unit includes the first metal electrode layer, pressure electric layer and the second metal electrode layer; the magneton junction unit includes a heavy metal layer, a first ferromagnetic insulator layer, an antiferromagnetic insulator layer and a second ferromagnetic insulator layer; a topological insulator unit includes a topological insulator layer and a substrate; assuming a magnetic The first ferromagnetic insulator layer and the second ferromagnetic insulator layer in the sub-junction have the same magnetic moment direction in the initial state, as shown in Figure 4, after the current is passed into the topological insulator layer 2, the spin-orbit torque Down will flip the magnetic moment in the first ferromagnetic insulator layer 4 , opposite to that of the second ferromagnetic insulator layer 6 , as shown in FIG. 5 . If the bulk acoustic wave excitation is applied, the inverse spin Hall effect voltage will also turn from high potential to low potential;

The structure of the bulk acoustic wave excitation unit is shown in Figure 6, an alternating voltage is applied through the first metal electrode layer 10 and the second metal electrode layer 8, and the piezoelectric layer 9 generates corresponding bulk acoustic waves accordingly;

The inverse spin Hall voltage of SOT-magnon junction-BAW in the case of two ferromagnetic insulator layers with different magnetic moment directions is as follows: when the magnetic moment directions in the two ferromagnetic insulator layers are the same, as shown in Figure 7 As shown by the line; showing a high level state; when the directions of the magnetic moments in the two ferromagnetic insulator layers are opposite, showing a low level state;

In summary, this embodiment can form a SOT-magnon-junction-BAW structure, adjust the orientation of the magnetic moment of the magnon-junction through a topological insulator, and use the bulk acoustic wave excitation as the power source of the magnon-junction to form a high-efficiency magnon-junction with practical application value. Low-power memory device prototype;

In addition to using the specific materials and structures of the magnetic sub-junction units in the above embodiments, other materials and magnetic sub-junction structures with similar effects may also be used.

It is easy for those skilled in the art to understand that the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention, All should be included within the protection scope of the present invention.

Claims (10)

1. A memory based on the magnetic substream effect, comprising: a topological insulator unit, a magnetic sub-junction unit and an acoustic wave excitation unit; the topological insulator unit, the magnetic sub-junction unit and the acoustic wave excitation unit are sequentially positioned on the substrate from bottom to top;

the topological insulator unit comprises a topological insulator layer and an electrode layer; the electrode layer is an electrode which is used for leading in current to the topological insulator layer; the topological insulator layer is used for overturning an adjacent ferromagnetic layer by using spin orbit moment when current is introduced;

the magnetic sub-junction unit comprises a first ferromagnetic insulator layer, an antiferromagnetic insulator layer, a second ferromagnetic insulator layer and a heavy metal layer from bottom to top; the first ferromagnetic insulator layer is used for changing the magnetic moment orientation under the action of spin orbit moment generated by the topological insulator layer; the magnetic moment of the second ferromagnetic insulator layer remains unchanged; the heavy metal layer is used for representing the magnetic sub-current transmitted in the second ferromagnetic insulator layer in the form of the reverse spin Hall effect voltage of a magnetic sub-junction; the antiferromagnetic insulator layer is used for separating the first ferromagnetic insulator layer and the second ferromagnetic insulator layer;

the acoustic body wave excitation unit comprises a first metal electrode layer, a piezoelectric layer and a second metal electrode layer from bottom to top; the first metal electrode layer and the second metal electrode layer are electrodes for applying alternating voltage; the piezoelectric layer is used for generating acoustic body waves under the action of alternating voltage, the acoustic body waves are transmitted downwards, and magnetic sub-flows are generated in the magnetic sub-junction units;

when the first ferromagnetic insulator layer and the second ferromagnetic insulator layer have the same magnetic moment direction, the reverse spin Hall voltage of the magnetic junction is high level under the action of acoustic wave excitation, current is introduced into the topological insulator layer, after the magnetic moment of the first ferromagnetic insulator layer is overturned, the current is stopped being introduced into the topological insulator layer, and the reverse spin Hall voltage of the magnetic junction is low level under the action of acoustic wave excitation; when the first ferromagnetic insulator layer and the second ferromagnetic insulator layer have opposite magnetic moment directions, the reverse spin Hall voltage of the magneton junction is converted from low level to high level under the action of acoustic wave excitation before and after the current is introduced into the topological insulator layers.

2. The memory of claim 1, wherein the topological insulator layer is grown on the substrate by magnetron sputtering or molecular beam epitaxy, and the electrode disposed over the topological insulator layer is grown by magnetron sputtering, electron beam evaporation plating, or thermal evaporation plating.

3. The memory of claim 2, wherein the topological insulator layer is Bi _x Sb _1-x 、Bi ₂ Se ₃ 、Sb ₂ Te ₃ Or Bi ₂ Te ₃ The method comprises the steps of carrying out a first treatment on the surface of the The electrode is Al, cr, cu, mo or Ag; wherein x is more than 0 and less than 1.

4. The memory of claim 1, wherein the first ferromagnetic insulator and the second ferromagnetic insulator layer are Y ₃ Fe ₅ O ₁₂ 、CoFe ₂ O ₄ Or NiFe ₂ O ₄ The method comprises the steps of carrying out a first treatment on the surface of the The antiferromagnetic insulator layer is NiO, fe ₂ O ₃ 、Cr ₂ O ₃ 、MgO、MnO、FeO、CoO、BiFeO ₃ 、LaMnO ₃ 、La ₂ CuO ₄ 、TmFeO ₃ 、ZnCr ₂ O ₄ 、F ₂ 、CuCl ₂ 、FeCl ₂ 、MnF ₂ 、FeF ₂ Or KNIF ₃ The method comprises the steps of carrying out a first treatment on the surface of the The heavy metal layer is V, cr, cu, nb, mo, ru, rh, pd, ag, hf, ta, W, re, ir, pt or Au.

5. The memory according to claim 4, wherein the heavy metal layer is deposited by a magnetron sputtering film plating method, a thermal evaporation film plating method or an electron beam evaporation film plating method, and is prepared by patterning by photolithography.

6. The memory according to claim 1, wherein the first metal electrode layer and the second metal electrode layer are prepared by deposition by a magnetron sputtering plating method, a thermal evaporation plating method, or an electron beam evaporation plating method; the piezoelectric layer is deposited by a magnetron sputtering method and is prepared by photoetching and patterning.

7. The memory of claim 6, wherein the first metal electrode layer and the second metal electrode layer are V, cr Cu, nb, mo, ru, rh, pd, ag, hf, ta, W, re, ir, pt, or Au; the piezoelectric layer is PZT, alN or PVDF.

8. The memory of claim 2, wherein the substrate has a thickness of 500 μm and the topological insulator layer has a thickness of 5nm to 15nm; the thickness of the electrode is 20 nm-50 nm.

9. The memory of claim 4 or 5, wherein the first ferromagnetic insulator layer is 20nm to 30nm thick and the antiferromagnetic insulator layer is 5nm to 20nm thick; the second ferromagnetic insulator layer is 40 nm-50 nm; the thickness of the heavy metal layer is 5 nm-20 nm.

10. The memory according to claim 6 or 7, wherein a thickness of the first metal electrode layer is 20nm to 100nm; the thickness of the second metal electrode layer is 20 nm-100 nm; the thickness of the piezoelectric layer is 20 nm-100 nm.