Full-electric-control Van der Waals multiferroic tunnel junction and simulation method and application thereof

Abstract

The invention relates to the technical field of electronic devices, in particular to a full-electric-control Van der Waals multiferroic tunnel junction and a simulation method and application thereof. The full-electric-control Van der Waals multiferroic tunnel junction comprises a left electrode area, a right electrode area and a center scattering area connected with electrodes at the two ends; the central scattering region comprises a ferroelectric layer and an antiferromagnetic layer; the ferroelectric layer and the antiferromagnetic layer are stacked through Van der Waals force; the left electrode region and the right electrode region are in the same stress field. Ferroelectric and antiferromagnetic materials are used as a central scattering region of the tunnel junction, and the antiferromagnetic magnetism is turned by a unique spontaneous polarization field of the ferroelectric material, so that four different resistance states are realized, and a complete spin polarization current, a large tunnel resistance ratio and a magnetoresistance value are generated. The multiferroic tunnel junction is simple in design, and different materials interact through Van der Waals force, so that the structure adaptability is very high, the mismatch rate is relatively low, and the cost is relatively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic devices, and particularly to a fully electrically controlled van der Waals multiferroic tunnel junction, a simulation method thereof, and an application thereof. Background Art

[0002] With the rapid development of the information age, enabling efficient storage of a large amount of data has become one of the most critical and urgent problems faced by modern society. China has entered an era of storage in units of "T", where the storage capacity of a single hard disk can reach thousands of "GB", and cloud storage platforms can even achieve storage in units of "PB". To achieve large-scale storage, faster and more efficient read and write functions are required to improve data transmission efficiency, enabling more convenient access and sharing of data. However, traditional oxides are limited by the tunnel effect and their inherent defects, such as external defects, stray fields, surface states, and limited magnetic anisotropy, resulting in a relatively small magnetoresistance value and hindering their rapid switching in the memory resistance state, significantly increasing their power consumption and limiting their practical use in various applications. Therefore, achieving fully electrically controlled and mutually switchable high-order multi-configurations at the nanoscale is crucial for high-density memories.

[0003] The wide-bandgap semiconductor material gallium oxide (Ga 2 O 3 ) has a spontaneous ferroelectric polarization at room temperature, which can effectively regulate the electronic or magnetic behavior of the ferromagnetic layer for non-volatile electrical control. Combining the advantages of atomically thin semiconductors, it can be used in small-size logic and ferroelectric non-volatile memories. The magnetic material chromium iodide (CrI 3 ) can serve as a magnetic barrier layer due to the double spin-filtering effect and achieve extremely high non-volatile magnetoresistance. Its strong spin dynamics and ultrafast terahertz can solve the problem of ferromagnetic stray fields and have wide applications in high-density and ultrafast information devices. In the field of information storage, more functions can be achieved through the multiple ferroic orders of multiferroic heterojunctions and their coupling effects. Different information bits can be stored simultaneously using the polarization state of ferroelectric materials and the magnetization state of ferromagnetic materials. This multi-state storage method can significantly improve storage density. However, the associated power consumption due to magnetic flipping in response to external magnetic fields and spin current control remains a challenge.

[0004] In view of this, the present invention provides a solution for fully electrically controlled magnetization states. By adding a ferroelectric layer to the van der Waals magnetic barrier layer, the flipping of the magnetization direction controlled by the internal electric field is achieved, enabling the application of multi-configuration non-volatile memories and providing a theoretical support for the development of high-speed, high-energy efficiency, and high-performance computing, as well as ferroelectric data memories. Summary of the Invention

[0005] One of the objectives of the present invention is to provide a fully electrically controlled van der Waals multiferroic tunnel junction, in which the band offset and interfacial charge transfer caused by the ferroelectric polarization field result in high current transmission efficiency, and both the tunnel resistance ratio and magnetoresistance value are relatively large.

[0006] Another objective of the present invention is to provide a simulation method for a fully electrically controlled van der Waals multiferroic tunnel junction, which has a simple design and is easy to adjust.

[0007] A third objective of the present invention is to provide a fully electrically controlled van der Waals multiferroic tunnel junction, its simulation method, and applications.

[0008] The solution adopted by the present invention to achieve the first objective is as follows: A fully electrically controlled van der Waals multiferroic tunnel junction includes a left electrode region, a right electrode region, and a central scattering region connected to both ends of the electrodes; the central scattering region includes a ferroelectric layer and an antiferromagnetic layer; the ferroelectric layer and the antiferromagnetic layer are stacked by van der Waals forces; the left electrode region and the right electrode region are under the same stress field.

[0009] Preferably, the ferroelectric layer and the antiferromagnetic layer in the central scattering region cause the magnetization of the antiferromagnet to reverse through the spontaneous polarization field, realizing four different resistance states.

[0010] Preferably, the ferroelectric layer in the central scattering region is bilayer Ga 2 O 3 , and the antiferromagnetic layer is bilayer CrI 3 .

[0011] Preferably, the left electrode region, the central scattering region, and the right electrode region of the tunnel junction are stacked by van der Waals forces into a sandwich structure, and the vacuum layer forms a natural barrier layer.

[0012] Preferably, both the left electrode region and the right electrode region adopt layered electrode materials, including at least one of Au, Pt, Ag, and graphene.

[0013] The solution adopted by the present invention to achieve the second objective is as follows: A simulation method for the above-mentioned fully electrically controlled van der Waals multiferroic tunnel junction includes the following steps:

[0014] S1: Construct a van der Waals interface model of the ferroelectric layer / antiferromagnetic layer. The two materials are stacked by van der Waals forces to form a four-layer structure, obtaining a heterojunction model.

[0015] S2: According to the heterojunction model constructed in S1, through density functional theory, perform first-principles calculations on the van der Waals interface model of the ferroelectric layer / antiferromagnetic layer, optimize the lattice constants of the structure, obtain the electron density of the system through self-consistent field iteration, determine the heterostructure with the most stable energy, and further process and analyze the structural work function, binding energy, energy band structure, density of states, and differential charge density of the system using the obtained electron wave function and electron density, and select the best heterojunction model.

[0016] S3: Use the best heterojunction model selected in S2 as the central scattering region of the tunnel junction, and use the vacuum layer between the ferroelectric layer and the antiferromagnetic layer as the natural barrier layer. Continuously stack layered electrode material layers at both ends of the central scattering region as the left and right electrode regions of the tunnel junction to form a multiferroic tunnel junction with an electrode - heterojunction - electrode sandwich structure;

[0017] S4: For the multiferroic tunnel junction constructed according to S3, use the non - equilibrium Green's function combined with density functional theory to study the electron transport properties of the tunnel junction, and set the optimal parameters to match the actual production process.

[0018] Preferably, in step S1, the van der Waals interface model of the ferroelectric layer / antiferromagnetic layer is the Ga 2 O 3 / CrI 3 van der Waals interface model, the ferroelectric layer is bilayer Ga 2 O 3 and the antiferromagnetic layer is bilayer CrI 3 .

[0019] Preferably, in step S3, the electrode material layers all use layered electrode materials, including at least one of Au, Pt, Ag, and graphene.

[0020] Preferably, in step S4, the parameters include exchange - correlation functional, pseudopotential, boundary conditions, cut - off energy, temperature, pressure, and electric field.

[0021] The solution adopted to achieve the third object of the present invention is: an application of the fully - electrically - controlled van der Waals multiferroic tunnel junction, applying the fully - electrically - controlled van der Waals multiferroic tunnel junction to a data memory, a processor, a high - frequency oscillator, or a filter.

[0022] The present invention uses ferroelectric and antiferromagnetic materials as the central scattering region of the tunnel junction. The unique spontaneous polarization field of the ferroelectric material causes the magnetization of the antiferromagnet to flip, thereby realizing four different resistance states and generating a fully spin - polarized current and large tunnel resistance ratios and magnetoresistance values.

[0023] Specifically, a simulation method for a fully - electrically - controlled van der Waals multiferroic tunnel junction includes the following steps:

[0024] S1: Construct a Ga 2 O 3 / CrI 3 van der Waals interface model. In the experimental sample, it shows CrI 3It is a layered structure. The Cr atomic layer has a hexagonal arrangement, with six I atoms around each Cr atom. The I atomic layer is also composed in a hexagonal arrangement. These Cr atomic layers play a role in supporting and stabilizing in the middle of the crystal. The layers are connected by van der Waals interactions, which are relatively weak, enabling the layers to slide relatively easily in the lattice. The AB stacking of the double-layer high-temperature phase of CrI 3 exhibits stable interlayer antiferromagnetic coupling. Ferroelectric Ga 2 O 3 is a typical hexagonal crystal system structure. The O atoms are arranged in a hexagonal close packing, and the Ga atoms occupy the hexagonal voids. The two materials form a four-layer structure through van der Waals stacking. Therefore, the lattice mismatch rate is less than 5% during the modeling process.

[0025] S2: Based on the Ga 2 O 3 / CrI 3 van der Waals interface model (heterojunction model) constructed in S1, through density functional theory, perform first-principles calculations on the Ga 2 O 3 / CrI 3 van der Waals interface model, optimize the lattice constants of the structure, obtain the electron density of the system through self-consistent field iteration, determine the most energy-stable structure, and use the obtained electron wave functions (the initial electron density obtained through self-consistent calculation, solve the Kohn-Sham equation to obtain the electron wave functions and energy levels, and recalculate the electron density based on the electron wave functions) and electron density to further process and analyze characteristic parameters such as the structural work function, binding energy, band structure, density of states, and differential charge density of the system, and select the best heterojunction model.

[0026] S3: Based on the best heterojunction model selected in S2 as the central scattering region of the tunnel junction, the vacuum layer between the Ga 2 O 3 and CrI 3 layers is used as the natural barrier layer, and any one of layered Au, Pt, Ag, and graphene is continuously stacked at both ends of the scattering region as the left electrode region and the right electrode region of the tunnel junction, forming a sandwich-structured multiferroic tunnel junction.

[0027] S4: For the multiferroic tunnel junction constructed according to S3, the electron transport properties of the tunnel junction are studied using the non-equilibrium Green's function combined with density functional theory, and the best parameters are set, specifically including the exchange-correlation functional, pseudopotential, boundary conditions, cut-off energy, temperature, pressure, and electric field, to achieve a process that matches the actual production process.

[0028] The present invention has the following advantages and beneficial effects:

[0029] (1) The present invention uses ferroelectric and antiferromagnetic materials as the central scattering region of the tunnel junction. The unique spontaneous polarization field of the ferroelectric material causes the magnetization of the antiferromagnet to flip, thereby achieving four different resistance states and generating a fully spin-polarized current, as well as a large tunnel resistance ratio and magnetoresistance value.

[0030] (2) The multiferroic tunnel junction in the present invention has a simple design. Different materials interact with each other through van der Waals forces, so the structural compatibility is very high, the mismatch rate is relatively low, and the cost is relatively reduced.

[0031] (3) For the multiferroic tunnel junction in the present invention, applying different intensities of electric fields to the electrodes will cause the ferroelectric to flip extremely quickly, and the band offset and interfacial charge transfer caused by the ferroelectric polarization field result in a high current transmission efficiency. The four different structures of the multiferroic tunnel junction in the present invention will exhibit different transport characteristics in an electric field, such as rectification characteristics, negative differential resistance effect, spin filtering effect, and switching diode characteristics, etc., which are beneficial to the application of the present invention in more fields such as memories, filters, and oscillators. Description of the Drawings

[0032] Figure 1 It is the device structure diagram of the first resistance state of the fully electrically controlled van der Waals multiferroic tunnel junction in Embodiment 1 of the present invention;

[0033] Figure 2 It is the device structure diagram of the second resistance state of the fully electrically controlled van der Waals multiferroic tunnel junction in Embodiment 2 of the present invention;

[0034] Figure 3 It is the device structure diagram of the third resistance state of the fully electrically controlled van der Waals multiferroic tunnel junction in Embodiment 3 of the present invention;

[0035] Figure 4 It is the device structure diagram of the fourth resistance state of the fully electrically controlled van der Waals multiferroic tunnel junction in Embodiment 4 of the present invention;

[0036] Figure 5 It is the curve of current varying with voltage of the fully electrically controlled multiferroic tunnel junction in Embodiment 1 under the application of an electric field;

[0037] Figure 6 It is the curve of current varying with voltage of the fully electrically controlled multiferroic tunnel junction in Embodiment 2 under the application of an electric field;

[0038] Figure 7 It is the curve of current varying with voltage of the fully electrically controlled multiferroic tunnel junction in Embodiment 3 under the application of an electric field;

[0039] Figure 8 It is the curve of current varying with voltage of the fully electrically controlled multiferroic tunnel junction in Embodiment 4 under the application of an electric field;

[0040] Figure 9It is a schematic diagram of the heterojunction energy band structure corresponding to the four different resistance states in Embodiments 1-4, where (a) is the schematic diagram of the heterojunction energy band structure corresponding to the first resistance state in Embodiment 1; (b) is the schematic diagram of the heterojunction energy band structure corresponding to the second resistance state in Embodiment 2; (c) is the schematic diagram of the heterojunction energy band structure corresponding to the third resistance state in Embodiment 3; (d) is the schematic diagram of the heterojunction energy band structure corresponding to the fourth resistance state in Embodiment 4. Detailed implementation manners

[0041] For a better understanding of the present invention, the following embodiments further illustrate the present invention, but the content of the present invention is not limited to the following embodiments.

[0042] In the present invention, the tunnel junction uses a multi-ferroic heterojunction constructed of an interlayer-dependent antiferromagnetic bilayer chromium iodide and a bilayer ferroelectric gallium oxide material as the central scattering region, and uses a metal gold with good conductivity or a semiconductor graphene with excellent properties as the electrode region. Therefore, the present invention utilizes the electromagnetic coupling effect between an antiferromagnet without stray fields and a ferroelectric semiconductor with spontaneous polarization to realize multi-ferroic tunnel junction devices with different configurations.

[0043] Embodiment 1

[0044] As Figure 1 shown, a device configuration diagram of the first configuration of a fully electrically controlled van der Waals multi-ferroic tunnel junction provided in this embodiment selects two materials with different properties for van der Waals stacking, and uses a four-layer multi-ferroic heterostructure composed of a double-layer ferroelectric layer and a magnetic bilayer with a 2×2 supercell. The ferroelectric layer is polarized to the left, and the ferroelectric polarization is used to effectively control the electron injection at two different interfaces, thereby realizing the transformation of various magnetic properties, and the double-layer magnetic layer is transformed into an antiferromagnet with opposite spin directions. The most energy-stable stacking method is selected for first-principles calculation, and simulation and analysis are carried out on performance parameters such as the lattice constant, energy band structure, density of states, electrostatic potential, binding energy, and differential charge density of the structure to ensure that the constructed interface model has excellent properties and realizes the device performance that can work stably under high temperature and high pressure.

[0045] Embodiment 2

[0046] As Figure 2As shown in the figure, the device configuration diagram of the second configuration of a fully electronically controlled van der Waals multiferroic tunnel junction provided in this embodiment. Under the setting conditions of Embodiment 1, the ferroelectric polarization direction of the interface contact layer in the central scattering region flips to the right. The polarization field generated by the polarization reversal also flips the spins of the ferromagnetic materials in contact with the interface to the right, and the bilayer magnetic layer changes to ferromagnetic with the same spin direction. First-principles calculations were performed on the obtained van der Waals heterojunctions with different polarization and spin directions. The lattice of the four-layer structure was optimized, and then density functional theory was used to calculate performance parameters such as the band structure, density of states, electrostatic potential, binding energy, and differential charge density of the structure, constructing the multiferroic tunnel junction in this resistance state and testing its transport performance under an electric field.

[0047] Embodiment 3

[0048] As Figure 3 shown in the figure, the device configuration diagram of the third configuration of a fully electronically controlled van der Waals multiferroic tunnel junction provided in this embodiment. Under the setting conditions of Embodiment 2, the ferroelectric polarization directions in the central scattering region flip together. The polarization field generated by the polarization reversal flips the spins of the ferromagnetic materials in contact with the interface to the left, and the bilayer magnetic layer changes back to antiferromagnetic with opposite spin directions. Since chromium ions in the antiferromagnetic material have unpaired electrons, the presence of iodine ions will enhance the spin-orbit coupling effect in the system. In the bilayer structure, this strong spin-orbit coupling effect is more significant, for example, it can generate spin-polarized current. The same property calculations and transport performance tests as in Embodiments 1 and 2 were performed on the model.

[0049] Embodiment 4

[0050] As Figure 4 shown in the figure, the device configuration diagram of the third configuration of a fully electronically controlled van der Waals multiferroic tunnel junction provided in this embodiment. Under the setting conditions of Embodiment 3, the ferroelectric polarization direction of the central scattering region close to the interface contact layer flips. The polarization field generated by the polarization reversal affects the spins of the ferromagnetic materials in contact with the interface to flip, and the bilayer magnetic layer changes to ferromagnetic with the same spin direction. The same property calculations and transport performance tests as in Embodiments 1 - 3 were performed on the model.

[0051] As Figures 5 - 8 shown in the figure, the test results of the volt-ampere characteristic curves of the four different fully electronically controlled multiferroic tunnel junctions in Embodiments 1 - 4. The test method combines density functional theory and non-equilibrium Green's function (DFT + NEGF). Density functional theory is used to calculate the electronic structure of the device scattering region and electrodes to obtain the corresponding Hamiltonian and density of electronic states, etc., and then substitute them into the framework of NEGF to solve the non-equilibrium Green's function. While considering effects such as electron correlation effects, quantum tunneling, and scattering, the transmission coefficient and scattering matrix of electrons in the device are obtained. The combination of the two accurately describes the entire transport process of electrons.

[0052] Among them,Figure 5 It is the current curve diagram of the first configuration under positive and negative bias voltages respectively. In the figure, the square dotted line represents the total current, the circular dotted line is the current with spin up, and the triangular dotted line is the current with spin down. When a positive bias voltage is applied, the total current is jointly dominated by the currents with spin up and down, showing an increasing trend. The current with spin up first increases and then decreases, finally reaching a small peak and then continuing to increase. When a negative bias voltage is applied, the current conducts negatively and shows a continuously increasing current. The change trend of the current with spin up is basically the same as that of the total current. The results show that the current under positive bias is greater than that under negative bias, and it is accompanied by spin filtering effect and negative differential resistance effect.

[0053] Figure 6 It is the current curve diagram of the second configuration under positive and negative bias voltages respectively. In the figure, the square dotted line represents the total current, the circular dotted line is the current with spin up, and the triangular dotted line is the current with spin down. When a positive voltage is applied, the current shows a non-conducting state; under negative bias voltage, the current can conduct quickly and is mainly dominated by the current with spin down, showing a general trend of increasing first and then decreasing, forming a current peak within a small voltage range, similar to the switching diode effect.

[0054] Figure 7 It is the current curve diagram of the third configuration under positive and negative bias voltages respectively. In the figure, the square dotted line represents the total current, the circular dotted line is the current with spin up, and the triangular dotted line is the current with spin down. Under positive bias voltage, the current starts to conduct rapidly after 0.2V; while under negative bias voltage, a current peak can be reached, and the current is mainly dominated by the current with spin down. The transport performance test shows that the current under negative bias exhibits obvious spin filtering effect and negative differential resistance effect.

[0055] Figure 8 It is the current curve diagram of the fourth configuration under positive and negative bias voltages respectively. In the figure, the square dotted line represents the total current, the circular dotted line is the current with spin up, and the triangular dotted line is the current with spin down. The current curve shows a situation completely opposite to that of Figure 3 When a positive voltage is applied, the current conducts quickly and can reach a small current peak; while the current under negative bias conducts slowly and starts to conduct at a bias voltage of -0.2V, showing a gradually increasing current trend and obtaining a larger current than that under positive bias. The currents under both positive and negative bias voltages are mainly dominated by the current with spin down, having a perfect spin filtering effect.

[0056] Figure 9It is a schematic diagram of the heterojunction energy band structure corresponding to the four different resistance states in Embodiments 1-4. The solid lines represent the energy bands with spin up, while the dashed lines represent the energy bands with spin down. Four structural interface models were constructed and selected, using two different materials, namely ferroelectric gallium oxide with a 2×2 supercell and bilayer chromium iodide with a single cell. To avoid the periodic influence of two adjacent structures, a vacuum layer with sufficient thickness was set. Density functional theory was used for the calculation. The exchange-correlation functional adopted the generalized gradient approximation and the PBE functional. A 9×9×1 k-point was used to sample the Brillouin zone, and the DFT-D3 approximation method was adopted for the interlayer van der Waals interaction force. To avoid the underestimation of the band gap in the calculation of the energy band by the PBE method, the HSE06 hybrid functional was simultaneously used to calculate the energy band structure. It can be seen from the energy band structure that as the spin direction changes, the energy band structure near the Fermi level also changes, which is beneficial to realizing the transport performance of devices with different properties.

[0057] The present invention is different from the traditional oxide magnetic tunnel junction, which is only used to control the tunneling current of electrons, has a single performance, and has problems such as a large starting voltage and high power consumption. The present invention adopts multiple parameters such as ferroelectricity and ferromagnetism, and can realize the mutual regulation of multiple physical properties such as electricity, magnetism, and force. The polarization field regulates the direction of the magnetic moment, while the magnetic field can act on the electric polarization in turn, so as to realize the regulation of high and low resistance states. This high-resistance characteristic enables the multiferroic heterojunction to be used as an excellent insulating layer or resistance element in electronic devices, which helps to control the transmission and distribution of current, realize the precise regulation of current, and thus reduce problems such as current leakage. The performance transformation of the multiferroic heterojunction can be achieved under a relatively low electric field or magnetic field during the whole process, and it can be used to construct and develop more functional low-power electronic devices.

[0058] The above is the preferred implementation manner of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. It should be pointed out that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and changes can still be made, and these improvements and changes are also regarded as the protection scope of the present invention.

Claims

1. A fully electrically controlled van der Waals multiferroic tunnel junction, characterized in that: It includes a left electrode region, a right electrode region and a central scattering region connected to electrodes at both ends; the central scattering region includes a ferroelectric layer and an antiferromagnetic layer; the ferroelectric layer and the antiferromagnetic layer are stacked through van der Waals force; the left electrode region and the right electrode region are under the same stress field.

2. The fully electrically controlled van der Waals multiferroic tunnel junction according to claim 1, characterized in that: The ferroelectric layer and the antiferromagnetic layer in the central scattering region have their antiferromagnetic magnetism reversed through a spontaneous polarization field, thereby realizing four different resistance states.

3. The fully electrically controlled van der Waals multiferroic tunnel junction according to claim 1, characterized in that: The ferroelectric layer in the central scattering region is a double-layer Ga2O3, and the antiferromagnetic layer is a double-layer CrI3.

4. The fully electrically controlled van der Waals multiferroic tunnel junction according to claim 1, characterized in that: The left electrode region, the central scattering region and the right electrode region of the tunnel junction are stacked into a sandwich structure through van der Waals forces, and the vacuum layer forms a natural barrier layer.

5. The fully electrically controlled van der Waals multiferroic tunnel junction according to claim 1, characterized in that: The left electrode region and the right electrode region are both made of layered electrode materials, including at least one of Au, Pt, Ag, and graphene.

6. A simulation method for a fully electrically controlled van der Waals multiferroic tunnel junction according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1: Construct a van der Waals interface model of ferroelectric layer / antiferromagnetic layer. The two materials are stacked by van der Waals to form a four-layer structure, and a heterojunction model is obtained; S2: Based on the heterojunction model constructed in S1, the density functional theory is used to perform first-principles calculations on the ferroelectric layer / antiferromagnetic layer van der Waals interface model, optimize the lattice constant of the structure, obtain the electron density of the system through self-consistent field iteration, determine the most energy-stable heterostructure, and use the obtained electron wave function and electron density to further process and analyze the system's structural work function, binding energy, band structure, state density, and differential charge density to select the best heterojunction model; S3: Based on the best heterojunction model selected in S2, the central scattering region of the tunnel junction is used, the vacuum layer between the ferroelectric layer and the antiferromagnetic layer is used as a natural barrier layer, and layered electrode material layers are stacked at both ends of the central scattering region as the left electrode region and the right electrode region of the tunnel junction to form a multiferroic tunnel junction with an electrode-heterojunction-electrode sandwich structure; S4: Based on the multiferroic tunnel junction constructed in S3, the electron transport properties of the tunnel junction were studied using non-equilibrium Green's function combined with density functional theory, and the optimal parameters were set to achieve a process that matches the actual production process.

7. The simulation method of the fully electrically controlled van der Waals multiferroic tunnel junction according to claim 6, characterized in that: In step S1, the ferroelectric layer / antiferromagnetic layer van der Waals interface model is a Ga2O3 / CrI3 van der Waals interface model, the ferroelectric layer is a double layer of Ga2O3, and the antiferromagnetic layer is a double layer of CrI3.

8. The simulation method of the fully electrically controlled van der Waals multiferroic tunnel junction according to claim 6, characterized in that: In step S3, the electrode material layers all use layered electrode materials, including at least one of Au, Pt, Ag, and graphene.

9. The simulation method of the fully electrically controlled van der Waals multiferroic tunnel junction according to claim 6, characterized in that: In step S4, the parameters include exchange-correlation functional, pseudopotential, boundary conditions, cutoff energy, temperature, pressure and electric field.

10. An application of the fully electrically controlled van der Waals multiferroic tunnel junction according to any one of claims 1 to 5, characterized in that: The fully electrically controlled van der Waals multiferroic tunnel junction is applied to data storage, processors, high-frequency oscillators or filters.

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