Magnon junctions, magnon random access memories, microwave oscillators, detectors and electronic devices

Abstract

To provide a magnon junction, a magnon random access memory, a microwave oscillator, a detector, and an electronic apparatus.SOLUTION: A magnon junction includes: a first electrode layer formed of a nonmagnetic conductive material; a free magnetic layer provided on the first electrode layer and formed of a ferromagnetic conductive material; an antiferromagnetic barrier layer provided on the free magnetic layer and formed of an antiferromagnetic insulating material; a reference magnetic layer provided on the antiferromagnetic barrier layer and formed of the ferromagnetic conductive material; and a second electrode layer provided on the reference magnetic layer and formed of the nonmagnetic conductive material. The reference magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and a magnetic moment direction thereof is fixed along a perpendicular direction. The free magnetic layer has the perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and a magnetic moment direction thereof is reversible along a perpendicular direction. The antiferromagnetic barrier layer has the perpendicular magnetic anisotropy or the perpendicular magnetic moment.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to the field of magnetic devices, and in particular to magnon junctions and methods of operating the same, magnon random access memories (magnon random memories) including the magnon junctions, magnon microwave oscillators, magnon microwave detectors, magnon random number generators and magnon stochastic bit random number generators, and electronic devices including any one or more of these devices. [Background technology]

[0002] FIG. 1 shows an example of a magnon storage unit 100 based on a conventional magnetic tunnel junction (MTJ). As shown in FIG. 1, the magnon storage unit 100 includes a free magnetic layer 110, a non-magnetic barrier layer 120, and a reference magnetic layer 130. Here, the free magnetic layer 110 has a free magnetic moment, the reference magnetic layer 130 has a relatively fixed magnetic moment that is pinned, and the non-magnetic barrier layer 120 is typically formed of a metal oxide insulating material such as MgO, Al2O3, or MgAlO. When the magnetic moments of the free magnetic layer 110 and the reference magnetic layer 130 are aligned parallel, the magnon storage unit 100 has a small resistance and can correspond to a storage bit "0." When the magnetic moments of the free magnetic layer 110 and the reference magnetic layer 130 are aligned antiparallel, the magnon storage unit 100 has a large resistance and can correspond to a storage bit "1." The reverse is also possible. When writing data to the magnon storage unit 100, the vertical write current I w By applying a magnetic field, the direction of the magnetic moment of the free magnetic layer 110 can be changed by the spin transfer torque (STT) effect.

[0003] One of the problems with the STT writing method is that the perpendicular write current I wSince the non-magnetic barrier layer 120 needs to have a high current density, it is necessary to make it thin to reduce resistance. On the other hand, if the non-magnetic barrier layer 120 is thin, leakage current occurs during read operations due to the tunneling effect. When the memory unit array is large and the read speed is fast, the total amount of leakage current generated becomes very large, which affects the practical application of STT-type magnon random access memory. Furthermore, the ultra-thin non-magnetic barrier layer 120 is easily destroyed during long-term repeated write / erase processes, resulting in short circuits and chip failure, which significantly affects the chip's lifespan. Furthermore, the ultra-thin non-magnetic barrier layer 120 increases the difficulty of manufacturing processes to maintain the uniformity and consistency of large-capacity memory units.

[0004] Therefore, in view of one or more of the above-mentioned problems, there remains a need for improved magnon storage units. Summary of the Invention [Problem to be solved by the invention]

[0005] From a physics perspective, in addition to electrons, which are spin carriers, particles such as magnons, neutrons, and other quasiparticles can also possess spin angular momentum. Research on magnon spin, in particular, has recently attracted widespread attention. Magnons are spin-wave quasiparticles, representing collective excitations of coherent electron spin systems in a magnon-ordered system. Each quantized magnon possesses a spin angular momentum equal to a single reduced Planck constant. Furthermore, the wave nature of magnons offers several capabilities not possible with conventional electron-based spin devices. For example, magnons can significantly reduce the power consumption of spin devices by providing long-range spin information without Joule heating. Furthermore, magnon transfer torque can reliably flip magnetic moments, offering enormous potential for future applications in information storage.

[0006] One aspect of the present invention provides a magnon junction that can overcome one or more problems present in conventional reversal methods by using magnons to assist the reversal of magnetic moments. The present invention also provides various devices based on the magnon junction, such as a magnon random access memory, a magnon microwave oscillator, a magnon microwave detector, a magnon random number generator, and a magnon stochastic bit random number generator, as well as electronic equipment including any one or more of these devices. [Means for solving the problem]

[0007] In one aspect of the embodiment of the present disclosure, a magnon junction (MJ) is provided, which includes a first electrode layer made of a nonmagnetic conductive material, a free magnetic layer provided on the first electrode layer and made of a ferromagnetic conductive material, and an antiferromagnetic insulating layer provided on the free magnetic layer. a reference magnetic layer provided on the antiferromagnetic barrier layer and formed of a ferromagnetic conductive material; and a second electrode layer provided on the reference magnetic layer and formed of a non-magnetic conductive material, wherein the reference magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is fixed along the perpendicular direction; the free magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is reversible along the perpendicular direction; there is exchange coupling at the interface between the antiferromagnetic barrier layer and the ferromagnetic conductive material; and when the magnetic moment of the free magnetic layer is reversed, the magnetic moment of the antiferromagnetic barrier layer is also reversed, thereby reducing the current density required to reverse the magnetic moment of the free magnetic layer.

[0008] In one example, the first electrode layer and the second electrode layer are configured to apply a perpendicular reversal current, which is spin-polarized as it flows through the reference magnetic layer. At the interface between the reference magnetic layer and the antiferromagnetic barrier layer, a portion of the spin-polarized current is converted into a magnon current, which diffuses and is injected into the free magnetic layer through the antiferromagnetic barrier layer. A magnon transfer torque (MTT) is generated during the diffusion and injection, and another portion of the spin-polarized current tunnels into the free magnetic layer through the antiferromagnetic barrier layer. As a result, the direction of the magnetic moment of the free magnetic layer is reversed by the cooperative action of the magnon transfer torque (MTT) generated by the magnon current and the spin transfer torque (STT) generated by the spin-polarized current.

[0009] In one example, when the magnon current diffuses through the antiferromagnetic barrier layer, it further generates a magnon transfer torque (MTT) that reverses the directions of the magnetic moments aligned antiparallel to each other at the lattice points of the antiferromagnetic barrier layer, thereby reversing both the Néel vector direction of the antiferromagnetic barrier layer and the magnetic moment direction of the free magnetic layer.

[0010] In one example, the first electrode layer is formed of a heavy metal non-magnetic conductive material that exhibits the spin Hall effect.

[0011] In one example, the first electrode layer is configured to apply a first in-plane reversal current, which generates a spin-polarized current that diffuses in the free magnetic layer due to the spin Hall effect, and the spin-polarized current generates a spin-orbit torque (SOT) to reverse the magnetic moment of the free magnetic layer.

[0012] In one example, the first electrode layer and the second electrode layer are further configured to apply a second perpendicular reversal current, the second perpendicular reversal current being spin-polarized when flowing through the reference magnetic layer, a part of the spin-polarized current being converted into a magnon current at the interface between the reference magnetic layer and the antiferromagnetic barrier layer, and being diffused and injected into the free magnetic layer through the antiferromagnetic barrier layer, generating a magnon transfer torque (MTT), and another part of the spin-polarized current being tunneled into the free magnetic layer through the antiferromagnetic barrier layer, and the spin-polarized current generating a spin transfer torque (STT) for reversing the magnetic moment direction of the free magnetic layer, thereby forming a magneto-optical coupling between the magnon transfer torque (MTT) and the spin transfer torque (STT) generated by the second perpendicular reversal current and the spin-orbit torque (SBT) generated by the first in-plane reversal current. The magnetic moment direction of the free magnetic layer is reversed by the action of the SOT (Stable Oscillator Torque).

[0013] In one example, the ferromagnetic conductive material for forming the reference magnetic layer and the free magnetic layer is NiCo2O4, Fe3GeTe2, VSe2, FePt, FePd, CoPt, CoPd, [Fe / Pt] N , [Co / Pt] N , [Fe / Pd] N , [Co / Pd] N , FeCr, CoCr, FeTb, CoTb, GdFeCo, TbFeCo, ultra-thin Co-Fe-B and Co-Fe alloy films, where N is a positive integer greater than or equal to 1.

[0014] In one example, the antiferromagnetic insulating material for forming the antiferromagnetic barrier layer includes one or more of Cr2O3, CoO, NiO, FeO, MnO, MnF2, MnS, FeCl2, GdFeO3, NdFeO3, SmFeO3, BiCoO3, BiNiO3, and LaFeO3.

[0015] In one example, the antiferromagnetic structure of the antiferromagnetic insulating material for forming the antiferromagnetic barrier layer is type A, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of two adjacent lattice points and opposite to the direction of the magnetic moment of another adjacent lattice point, or type B, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of one adjacent lattice point and opposite to the direction of the magnetic moment of two other adjacent lattice points, or type C, i.e., the direction of the magnetic moment of one lattice point in the original cell is opposite to the direction of the magnetic moment of three adjacent lattice points, or the antiferromagnetic barrier layer has a spiral magnetic structure.

[0016] In one example, the heavy metal non-magnetic conductive material for forming the first electrode layer includes one or more of Pt, W, Ta, Pd, Ir, W, Bi, Mo, Pb, Hf, Ru, IrMn, PtMn, AuMn, Bi2Se3, Bi2Te3, and alloys or compounds of these heavy metals.

[0017] In one aspect of the embodiment of the present disclosure, there is provided a method for operating a magnon junction, the magnon junction including: a first electrode layer made of a nonmagnetic conductive material; a free magnetic layer provided on the first electrode layer and made of a ferromagnetic conductive material; an antiferromagnetic barrier layer provided on the free magnetic layer and made of an antiferromagnetic insulating material; a reference magnetic layer provided on the antiferromagnetic barrier layer and made of a ferromagnetic conductive material; and a second electrode layer provided on the reference magnetic layer and made of a nonmagnetic conductive material, wherein the reference magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is fixed along a perpendicular direction; the free magnetic layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is reversible along the perpendicular direction; and the antiferromagnetic barrier layer has perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is reversible along the perpendicular direction. The magnon junction has a perpendicular magnetic moment component, and there is exchange coupling at the interface between the antiferromagnetic barrier layer and a ferromagnetic conductive material, and when the magnetic moment of the free magnetic layer is reversed, the magnetic moment of the antiferromagnetic barrier layer is also reversed, thereby reducing the current density required to reverse the magnetic moment of the free magnetic layer. The method for operating the magnon junction includes the steps of: applying a perpendicular reversal current that flows perpendicularly through the magnon junction using the first electrode layer and the second electrode layer, the perpendicular reversal current being spin-polarized when it flows through the reference magnetic layer; and converting a part of the spin-polarized current into a magnon current at the interface between the reference magnetic layer and the antiferromagnetic barrier layer, diffusing the current, and injecting it into the free magnetic layer via the antiferromagnetic barrier layer, wherein a magnon transfer torque (Magnon) is generated during the diffusion and injection. and a step of generating a magnon transfer torque (MTT) generated by the magnon current and a spin transfer torque (STT) generated by the spin-polarized current by tunneling another part of the spin-polarized current through the antiferromagnetic barrier layer to the free magnetic layer, thereby reversing the magnetic moment direction of the free magnetic layer by the cooperation of the magnon transfer torque (MTT) generated by the magnon current and the spin transfer torque (STT) generated by the spin-polarized current.

[0018] In one example, the first electrode layer is formed of a heavy metal non-magnetic conductive material having a spin Hall effect, and the method further includes applying an in-plane reversal current through the first electrode layer, wherein the in-plane reversal current generates a spin-polarized current that diffuses in the free magnetic layer due to the spin Hall effect, and the spin-polarized current generates a spin-orbit torque (SOT) for reversing the magnetic moment of the free magnetic layer, whereby the direction of the magnetic moment of the free magnetic layer is reversed by the cooperation of the magnon transfer torque (MTT) and spin transfer torque (STT) generated by the perpendicular reversal current and the spin-orbit torque (SOT) generated by the in-plane reversal current.

[0019] In one example, the magnon flow further generates a magnon transfer torque (MTT) that also reverses the directions of magnetic moments aligned antiparallel to each other at different lattice points of the antiferromagnetic barrier layer, thereby reversing both the Néel vector direction of the antiferromagnetic barrier layer and the magnetic moment direction of the free magnetic layer.

[0020] In one aspect of an embodiment of the present disclosure, a magnon random access memory (mRAM) is provided that includes an array of a plurality of magnon storage units, each of which includes a magnon junction as described above.

[0021] One aspect of an embodiment of the present disclosure provides a magnon microwave oscillator (MMO), including the magnon junction described above and a current source that applies a current that flows perpendicularly through the magnon junction and generates a microwave oscillation signal across the magnon junction, wherein the magnitude of the current provided by the current source is adjustable to control the frequency and amplitude of the microwave oscillation signal output by both ends of the magnon junction by adjusting the magnitude of the magnon transfer torque and spin transfer torque (MTT+STT) in the magnon junction and thereby adjusting the frequency and amplitude of the precession of the magnetic moment of the free magnetic layer in the magnon junction.

[0022] One aspect of an embodiment of the present disclosure provides a magnon microwave detector (MMD) including: the magnon junction described above, wherein the magnetic moment of the magnon junction precesses in response to an alternating electromagnetic field generated by an external microwave signal; a current source that applies a detection current that flows perpendicularly through the magnon junction to generate a microwave oscillation signal across the magnon junction, wherein the frequency and amplitude of the microwave oscillation signal depend, respectively, on the frequency and intensity of the external microwave signal; and a signal analysis module that detects the frequency and amplitude of the microwave oscillation signal to determine the frequency and intensity of the external microwave signal.

[0023] One aspect of an embodiment of the present disclosure provides the above-described magnon junction, a current source that applies a continuous current that flows perpendicularly through the magnon junction, the continuous current having a predetermined current density so as to reduce the barrier height between the parallel and antiparallel states of the magnon junction, realize random reversals upon thermal perturbation, and output random signals at both ends of the magnon junction, and a magnon random number generator (MRNG).

[0024] In one aspect of an embodiment of the present disclosure, there is provided a magnon p-bit random number generator (MRNG) comprising the magnon junction described above, a current source applying a continuous current perpendicular to the magnon junction, the continuous current having a predetermined current density so as to reduce the barrier height between the parallel and antiparallel states of the magnon junction, thereby realizing random reversal upon thermal perturbation and outputting a random signal at both ends of the magnon junction, and the current source adjusting the magnitude of the continuous current to adjust the magnitude of the magnon transfer torque or spin transfer torque, thereby changing the probability of generating the parallel and antiparallel states and realizing a probability-adjustable random number generator.

[0025] In one aspect of an embodiment of the present disclosure, there is provided an electronic device including at least one of the magnon random access memory, the magnon microwave oscillator, the magnon microwave detector, the magnon random number generator, and the magnon stochastic bit random number generator.

[0026] These and other features and advantages of the present invention will become apparent from the following illustrative embodiments which are described with reference to the accompanying drawings. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic diagram of a conventional magnetic tunnel junction (MTJ) configuration. [Figure 2] 1 is a schematic diagram of a magnon junction configuration according to one embodiment of the present invention. [Figure 3] FIG. 10 is a schematic diagram of a magnon junction configuration according to another embodiment of the present invention. [Figure 4] FIG. 2 is a schematic diagram of magnetic moment directions of a magnon junction according to one embodiment of the present invention. [Figure 5A] Schematic illustration of the principle of spin transfer torque (STT) reversal upon application of a perpendicular reversal current. [Figure 5B] Schematic illustration of the principle of spin transfer torque (STT) reversal upon application of a perpendicular reversal current. [Figure 6A] Schematic illustration of the principle of magnon transfer torque (MTT) reversal upon application of a perpendicular reversal current. [Figure 6B] Schematic illustration of the principle of magnon transfer torque (MTT) reversal upon application of a perpendicular reversal current. [Figure 7A] Schematic illustration of the principle of spin-orbit torque (SOT) reversal upon application of an in-plane reversal current. [Figure 7B] Schematic illustration of the principle of spin-orbit torque (SOT) reversal upon application of an in-plane reversal current. [Figure 8] 1 is a schematic diagram of the configuration of a storage unit array of a magnon random access memory according to one embodiment of the present invention. [Figure 9] FIG. 10 is a schematic diagram of the configuration of a storage unit array of a magnon random access memory according to another embodiment of the present invention. [Figure 10] 1 is a schematic diagram of a configuration of a magnon microwave oscillator according to one embodiment of the present invention. [Figure 11] 1 is a schematic diagram of a magnon microwave detector configuration according to one embodiment of the present invention. [Figure 12] FIG. 1 is a schematic diagram of a magnon random number generator configuration according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] Exemplary embodiments of the present invention will now be described with reference to the drawings, which may not be drawn to scale.

[0029] 2 is a schematic diagram of a magnon junction 200 configuration according to one embodiment of the present invention. As shown in FIG. 2, the magnon junction 200 may include a first electrode layer 202, a free magnetic layer 210, an antiferromagnetic barrier layer 220, a reference magnetic layer 230, a pinned layer 240, and a second electrode layer 204.

[0030] 3 is a schematic diagram of a magnon junction 200' according to another embodiment of the present invention. As shown in FIG. 3, the magnon junction 200' may include a second electrode layer 204, a pinned layer 240, a reference magnetic layer 230, an antiferromagnetic barrier layer 220, a free magnetic layer 210, and a first electrode layer 202. FIG. 3 further illustrates that the magnon junction 200' (or the magnon junction 200) can function as a two-terminal device (lower left diagram) and a three-terminal device (lower right diagram). When functioning as a two-terminal device, the read current Iread and the perpendicular write current I write MTT+STT When functioning as a three-terminal element, a read current Iread and a vertical write current I write MTT+STT In addition, the in-plane write current I flows through the first electrode layer (the spin Hall effect (SHE) layer). write SOT may be further applied.

[0031] 2 and 3, spatial relationships in the present invention, such as terms like "upper" and "lower," refer only to relative spatial relationships and are not limited to any absolute direction. Hereinafter, for convenience of explanation, only the magnon junction 200 will be referred to, but this should be understood to also include the magnon junction 200'. Furthermore, similar to conventional magnetic tunnel junctions (MTJs), the structure of the magnon junction 200 can be modified in various ways, and a detailed description thereof will be omitted here. Furthermore, based on the principle of free layer inversion, devices can be divided into two-terminal devices (MTT+STT) and three-terminal devices (MTT+STT+SOT), which will be described in more detail below.

[0032] 4 shows the magnetic moment directions of the free magnetic layer 210, the antiferromagnetic barrier layer 220, and the reference magnetic layer 230. As shown in FIG. 4, the reference magnetic layer 230 has perpendicular magnetic anisotropy, and its magnetic moment direction M 230 may be fixed along the perpendicular direction. Note that the use of the pinned layer 240 allows the magnetic moment direction M of the reference magnetic layer 230 to be230 can be perpendicularly pinned, and such pinned layer 240 may be formed of an antiferromagnetic material such as IrMn. In some other embodiments, reference magnetic layer 230 may also employ a self-pinned structure, for example, include an artificial antiferromagnetic structure, in which case pinned layer 240 may be omitted.

[0033] The free magnetic layer 210 may also have perpendicular magnetic anisotropy, with its magnetic moment direction M 210 is reversible in the perpendicular direction, so that the magnetic moment M of the reference magnetic layer 230 230 and are arranged parallel or antiparallel to each other, which correspond to the low resistance state and the high resistance state of the magnon junction 200, respectively. Therefore, by utilizing this characteristic, the magnon junction 200 can be used as a memory device.

[0034] The antiferromagnetic barrier layer 220 also has perpendicular magnetic anisotropy. In the perpendicular direction, as shown in FIG. 4, the antiferromagnetic barrier layer 220 has magnetic moment directions aligned antiparallel to each other at the lattice points, for example, a perpendicular upward magnetic moment direction M 220a and the vertical downward magnetic moment direction M 220b 4, the Néel vector n of the antiferromagnetic barrier layer 220 is further shown.

[0035] Although FIG. 4 shows the magnetic moment directions of the free magnetic layer 210, antiferromagnetic barrier layer 220, and reference magnetic layer 230 as being perpendicularly upward or downward, they may also be tilted, with the tilt angle being within 60°, preferably within 45°, and more preferably within 30°. In other words, the free magnetic layer 210, antiferromagnetic barrier layer 220, and reference magnetic layer 230 each have perpendicular magnetic anisotropy with an in-plane component. The tilted magnetic anisotropy of the free magnetic layer 210 and antiferromagnetic barrier layer 220 allows for reversal of their magnetic moments with less current, eliminating the need for an external bias magnetic field. This will be described in more detail below.

[0036] The free magnetic layer 210 and the reference magnetic layer 230 may each be made of a ferromagnetic conductive material. Examples of ferromagnetic conductive materials that satisfy the above-mentioned configuration include NiCo2O4, Fe3GeTe2, VSe2, FePt, FePd, CoPt, CoPd, and [Fe / Pt]. N , [Co / Pt] N , [Fe / Pd] N , [Co / Pd] N , FeCr, CoCr, FeTb, CoTb, GdFeCo, TbFeCo, ultra-thin Co-Fe-B and Co-Fe alloy films, where N is a positive integer greater than or equal to 1.

[0037] The antiferromagnetic barrier layer 220 may be made of an antiferromagnetic insulating material. Examples of ferromagnetic conductive materials that satisfy the above-mentioned configuration include, but are not limited to, Cr2O3, CoO, NiO, FeO, MnO, MnF2, MnS, FeCl2, GdFeO3, NdFeO3, SmFeO3, BiCoO3, BiNiO3, and LaFeO3. In one exemplary embodiment, the antiferromagnetic structure of the antiferromagnetic insulating material for forming the antiferromagnetic barrier layer 220 may be type A, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of two adjacent lattice points and opposite to the direction of the magnetic moment of another adjacent lattice point, or type B, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of one adjacent lattice point and opposite to the direction of the magnetic moment of two adjacent lattice points, or type C, i.e., the direction of the magnetic moment of one lattice point in the original cell is opposite to the direction of the magnetic moment of three adjacent lattice points. In another exemplary embodiment, the antiferromagnetic barrier layer 220 may have a spiral magnetic structure.

[0038] In the present invention, achieving good perpendicular magnetic anisotropy is important. Therefore, the selection of materials for the free magnetic layer 210, antiferromagnetic barrier layer 220, and reference magnetic layer 230 is important. Not only can the materials themselves achieve the desired perpendicular magnetic anisotropy through an appropriate deposition process or a post-treatment process, such as thermal annealing in a magnetic field, but also the degree of matching between materials, such as lattice matching and interdiffusion, must be taken into consideration to form a high-quality layer structure and clear layer interfaces. Experiments have shown that selecting Cr2O3 to form the antiferromagnetic barrier layer 220 and NiCo2O4 to form the free magnetic layer 210 and reference magnetic layer 230 is preferable because it can achieve a high-quality multilayer structure of ferromagnetic layers and antiferromagnetic barrier layers with perpendicular magnetic anisotropy.

[0039] The first electrode layer 202 and the second electrode layer 204 may be formed of a non-magnetic metal material having good electrical conductivity. Preferably, the upper electrode layer further has good corrosion resistance to protect the underlying layer. Examples of such non-magnetic metal materials include, but are not limited to, Pt, Ta, etc.

[0040] In some embodiments, the first electrode layer 202 in contact with the free magnetic layer 210 may be formed of a heavy metal non-magnetic conductive material that has the spin Hall effect, examples of which include, but are not limited to, Pt, W, Ta, Pd, Ir, W, Mo, Bi, Pb, Hf, IrMn, PtMn, AuMn, Bi2Se3, and Bi2Te3.

[0041] The following describes methods of operating the magnon junction 200. In the first method, a reversal current (also called a write current) I flows vertically through the magnon junction 200 using the first electrode layer 202 and the second electrode layer 204. w By applying a reverse current I wThe magnetic moment direction of the free magnetic layer 210 may be reversed by the cooperation of the spin transfer torque (STT) and magnon transfer torque (MTT) induced by the magnetization. The following description will be given with reference to FIGS. 5A, 5B, 6A, and 6B.

[0042] First, as shown in Figure 5A, the vertical reversal current I W The spin-polarized current I is spin-polarized when it flows through the reference magnetic layer 230, and then passes through the antiferromagnetic barrier layer 220 and tunnels into the free magnetic layer 210. The spin-polarized current generates a spin transfer torque (STT) to reverse the magnetic moment direction of the free magnetic layer 210. Here, the vertical downward reversal current I shown in FIG. W (While shown as "electrons" in FIG. 5A, current can be understood here as electron flow. On the other hand, the illustrated current direction may be reversed if the direction of current is understood to be opposite to the direction of electron flow.) W First, in the reference magnetic layer 230, the magnetic moment direction M 230 When the spin-polarized current tunnels through the free magnetic layer 210, the spin-polarized current is converted into the magnetic moment M of the free magnetic layer 210 by the spin-polarized current. 210 and, according to the law of conservation of angular momentum, the magnetic moment M of the free magnetic layer 210 210 This generates a spin transfer torque acting on the free magnetic layer 210, causing its magnetic moment direction to approach that of the reference magnetic layer 230. This causes the magnetic moment M 210 is the magnetic moment M of the reference magnetic layer 230. 230 Flip in the same direction as

[0043] Figure 5B shows the vertical downward reversal current I wThe spin angular momentum 201a is oriented in the magnetic moment direction M of the reference magnetic layer 230 due to the filtering and reflection of the spin at the interface with the reference magnetic layer 230. 230 A part of the spin-polarized current, which is the same as the spin-polarized current 201b, penetrates the reference magnetic layer 230, and the spin angular momentum 201b is oriented in the magnetic moment direction M of the reference magnetic layer 230. 230 The other part of the spin-polarized current, which is opposite to the polarized current, is reflected by the free magnetic layer 210 and generates the magnetic moment M 210 experiences a spin transfer torque in the opposite direction, causing the magnetic moment M of the reference magnetic layer 230 230 is inverted in the opposite direction.

[0044] As shown in Figure 6A, a vertical downward reversal current I w is the magnetic moment direction M of the reference magnetic layer 230. 230 After obtaining the same spin angular momentum 201a as that of the reference magnetic layer 230, the spin angular momentum 201a is scattered at the interface between the reference magnetic layer 230 and the antiferromagnetic barrier layer 220, and the angular momentum is transferred to the antiferromagnetic barrier layer 220, and the magnetic moment direction M of the reference magnetic layer 230 is 230 The magnon current 203a can diffuse through the antiferromagnetic barrier layer 220 to the free magnetic layer 210, and the magnetic moment M of the free magnetic layer 210 210 and, according to the law of conservation of angular momentum, the magnetic moment M of the free magnetic layer 210 210 This generates a magnon transfer torque acting on the free magnetic layer 210, causing its magnetic moment direction to approach that of the reference magnetic layer 230. This causes the magnetic moment M 210 is the magnetic moment M of the reference magnetic layer 230. 230 Flip in the same direction as

[0045] The magnon current 203a is also induced by the magnetic moment M of the antiferromagnetic barrier layer 220. 220 (M 220a and M 220b6A ), which also flips the magnetic moment direction of the antiferromagnetic barrier layer 220. Because of the exchange coupling between the antiferromagnetic barrier layer 220 and the free magnetic layer 210, the flip of the magnetic moment of the antiferromagnetic barrier layer 220 can facilitate or lead to the flip of the magnetic moment of the free magnetic layer 210, thereby reducing the current density required to flip the magnetic moment of the free magnetic layer 210.

[0046] Next, a vertical upward reversal current I w is a magnetic moment direction M of the reference magnetic layer 230 due to the spin transmission and emission effect at the interface of the reference magnetic layer 230. 230 A part of the spin-polarized current, which is the same as the spin-polarized current 201b, is transmitted to the reference magnetic layer 230. The spin angular momentum 201b is oriented in the magnetic moment direction M of the reference magnetic layer 230. 230 The other part of the spin-polarized current opposite to the direction of the magnetic moment M of the reference magnetic layer 230 is reflected by the antiferromagnetic barrier layer 220 and the free magnetic layer 210. 230 5B), which is transferred to the antiferromagnetic barrier layer 220 and rotates the magnetic moment direction M of the reference magnetic layer 230. 230 The magnon current 203b can diffuse back to the free magnetic layer 210 through the antiferromagnetic barrier layer 220, increasing the magnetic moment M of the free magnetic layer 210. 210 and, according to the law of conservation of angular momentum, the magnetic moment M of the free magnetic layer 210 210 This generates a magnon transfer torque in the opposite direction acting on the magnetic moment M of the free magnetic layer 210. 210 is the magnetic moment M of the reference magnetic layer 230. 230 and flip it in the opposite direction.

[0047] The magnon current 203b is also induced by the magnetic moment M of the antiferromagnetic barrier layer 220. 220 (M 220a and M 220b6B ), which also flips its magnetic moment direction, as shown by the Neel vector n in FIG. 6B . Similarly, because of the exchange coupling between the antiferromagnetic barrier layer 220 and the free magnetic layer 210, the flipping of the magnetic moment of the antiferromagnetic barrier layer 220 can facilitate or lead to the flipping of the magnetic moment of the free magnetic layer 210, thereby reducing the current density required to flip the magnetic moment of the free magnetic layer 210.

[0048] As shown above in FIGS. 5A, 5B, 6A, and 6B, the configuration of the magnetic anisotropy of the antiferromagnetic barrier layer 220 and associated layers allows for a perpendicular reversal current I w The perpendicular reversal current I induces both the spin transfer torque (STT) and the magnon transfer torque (MTT) simultaneously, and the magnetic moment direction of the free magnetic layer 210 can be reversed by their combined action, thereby reducing the required density of the reversal current. w By changing the direction of the magnetization, the magnetic moment of the free magnetic layer 210 can be reversed to the desired direction, making the operation simple. Furthermore, since the magnetic moment of the antiferromagnetic barrier layer 220 can be reversed along with the magnetic moment of the free magnetic layer 210, the height of the reversal barrier due to the coupling effect of the antiferromagnetic barrier layer 220 can be reduced, thereby further reducing the reversal current density. Reducing the required reversal current density allows the antiferromagnetic barrier layer 220 to be relatively thicker, thereby avoiding the pinhole effect and preventing a large leakage current generated in the antiferromagnetic barrier layer 220 that is unacceptable in chip design. This is extremely advantageous when using a magnon junction as a storage unit device.

[0049] When the first electrode layer 202 in contact with the free magnetic layer 210 is made of a heavy metal non-magnetic conductive material with the spin Hall effect, an in-plane reversal current applied along the first electrode layer 202 may be used to assist in reversing the magnetic moment direction of the free magnetic layer 210, which is referred to herein as the second method, as will be described in detail below with reference to Figures 7A and 7B.

[0050] First, as shown in FIG. 7A, an in-plane reverse current I w When a magnetic field is applied (to the left in FIG. 7A), a spin-polarized current is generated on the surface of the first electrode layer 202 due to the spin Hall effect, and the current diffuses into the free magnetic layer 210, increasing the magnetic moment M 210 In the example of FIG. 7A, the magnetic moment M of the free magnetic layer 210 is 210 is the magnetic moment direction M of the reference magnetic layer 230 230 is inverted to be identical to

[0051] Next, as shown in FIG. 7B, an in-plane reverse current I flows in the opposite direction along the first electrode layer 202. w When applying (pointing to the right in Figure 7B), an in-plane reversal current I w generate spin-polarized currents with opposite electron polarization directions, and the currents diffuse into the free magnetic layer 210, increasing the magnetic moment M 210 In the example of FIG. 7B, the magnetic moment M of the free magnetic layer 210 is 210 is the magnetic moment direction M of the reference magnetic layer 230. 230 and flip it in the opposite direction.

[0052] 7A and 7B, the generated spin-polarized current can also diffuse to the interface of the antiferromagnetic barrier layer 220, transferring spin angular momentum to the antiferromagnetic barrier layer 220 and generating a magnon current. This magnon current can generate a magnon transfer torque (MTT) that flips the magnetic moment of the antiferromagnetic barrier layer 220, as shown in FIGS. 6A and 6B. As described above, due to the exchange coupling between the antiferromagnetic barrier layer 220 and the free magnetic layer 210, the reversal of the magnetic moment of the antiferromagnetic barrier layer 220 can facilitate or lead to the reversal of the magnetic moment of the free magnetic layer 210, thereby reducing the current density required to flip the magnetic moment of the free magnetic layer 210.

[0053] According to the above-mentioned first operating direction and second operating method, the resistance state of the magnon junction 200 can be changed by reversing the magnetic moment direction of the free magnetic layer 210, i.e., the data bit stored in the magnon junction 200 can be changed, and therefore these are also referred to as write methods. In some aspects, the above-mentioned first and second write methods can be used simultaneously to reverse the magnetic moment of the free magnetic layer 210 in the magnon junction 200, i.e., the magnetic moment of the free magnetic layer 210 can be reversed by the cooperation of the perpendicular reversal current and the in-plane reversal current, and therefore this may be referred to as a third write / reversal method, the principles of which will not be described here.

[0054] The magnon junction 200 can be read by applying a perpendicular read current to read the resistance state of the magnon junction 200, similar to a conventional magnetic tunnel junction (MTJ). The current density of the read current is much smaller than the current density of the reversal current (i.e., write current), so the magnetic moment direction of the free magnetic layer 210 in the magnon junction 200 is not changed.

[0055] One embodiment of the present invention further provides a magnon random access memory (mRAM), which may include an array of magnon storage units formed by the above-described magnon junctions 200. FIG. 8 shows a magnon storage unit array 300 including the magnon junctions 200 as two-terminal elements, in which a current / voltage is applied only to the upper and lower ends of the magnon junctions 200 to perform relevant access operations. FIG. 9 shows a magnon storage unit array 300' including the magnon junctions 200 (shown in FIG. 3) as three-terminal elements, in which, in addition to applying a current / voltage to the upper and lower ends of the magnon junctions 200, an in-plane current may be applied to a spin Hall effect (SHE) layer (a heavy metal non-magnetic conductive layer) in the magnon junctions 200 to perform relevant access operations.

[0056] First, as shown in FIG. 8 , a word line BLn and a power supply line SLn (where n represents the row number) are provided for each row of the array, and a select line SELp (where p represents the column number) is provided for each column of the array. One electrode layer of the magnon junction 200 is connected to the word line BLn, and the other electrode layer is connected to the power supply line SLn via a switch transistor 302, and the control gate of the switch transistor 302 is connected to the select line SELp. For example, when performing a write operation on the magnon junction 200 in the first row and first column, a write current is applied via the word line BL1 and power supply line SL1 in the first row, and a voltage is applied to the select line SEL1 in the first column to turn on the switch transistor 302 in the first column, completing the write operation on the magnon junction 200 in the first row and first column. In other words, a write operation is performed on the magnon junction 200 using the first operation method described above. Similarly, when performing a read operation on the magnon junction 200 in the first row and first column, for example, a read current is applied via the word line BL1 and power supply line SL1 in the first row, and a voltage is applied to the select line SEL1 in the first column to turn on the switch transistor 302 in the first column, thereby completing the read operation on the magnon junction 200 in the first row and first column. The specific principles of the write and read operations have been explained in detail in the above explanation of the magnon junction 200, so further explanation will be omitted here. Similarly, read and write operations may be performed individually on each magnon junction 200 in the array.

[0057] As shown in FIG. 9 , when the magnon junction 200 is formed as a three-terminal element, a first word line BLn1 and a second word line BLn2 (where n represents the row number) and a power supply line SLn are provided for each row of the array, and a selection line SELp (where p represents the column number) is provided for each column. One end of the spin Hall effect layer 202 of the magnon junction 200 is connected to the first word line BLn1, and the other end is connected to the power supply line SLn via a switch transistor 302, the control gate of which is connected to the selection line SELp. Furthermore, the second electrode layer 204 on the opposite side of the spin Hall effect layer 202 of the magnon junction 200 may be connected to the second word line BLn2. For example, when writing to the magnon junction 200 in the first row and first column, three write methods may be employed. In the first write method, the first word line BL11 is floated, a vertical write current is applied via the second word line BL12 and the power supply line SL1, a voltage is applied to the select line SEL1 of the first column to turn on the switch transistor 302 of the first column, and the write operation for the magnon junction 200 in the first row and first column is completed. In the second write method, the second word line BL12 is floated, an in-plane write current is applied via the first word line BL11 and the power supply line SL1, and a voltage is applied to the select line SEL1 of the first column to turn on the switch transistor 302 of the first column, and the write operation for the magnon junction 200 in the first row and first column is completed. In the third write method, a perpendicular write current is applied via the second word line BL12 and the power supply line SL1, and at the same time, an in-plane write current is applied via the first word line BL11 and the power supply line SL1, and a voltage is applied to the select line SEL1 of the first column to turn on the switch transistor 302 of the first column, thereby completing the write to the magnon junction 200 in the first row and first column using both the perpendicular write current and the in-plane write current. These three write methods have all been described in detail above in the description of the operation method of the magnon junction 200, and therefore will not be described here.For example, when performing a read operation on the magnon junction 200 in the first row and first column, the first word line BL11 is floated, a read current is applied via the second word line BL12 and the power supply line SL1, and a voltage is applied to the select line SEL1 in the first column to turn on the switch transistor 302 in the first column, thereby completing the read operation on the magnon junction 200 in the first row and first column. Similarly, read and write operations may be performed individually on each magnon junction 200 in the array.

[0058] FIG. 10 is a schematic diagram of a magnon microwave oscillator (MMO) 400 according to one embodiment of the present invention. As shown in FIG. 10 , the magnon microwave oscillator 400 may include a magnon junction 200 and a current source for applying a current that flows perpendicularly through the magnon junction 200. The current source 402 may be an adjustable current source that can adjust the magnitude of the current it supplies. An inductor 404 may be connected in series with the magnon junction 200 for impedance matching. When a current flows perpendicularly through the magnon junction 200, controlling the magnitude of the current prevents the magnetic moment of the free magnetic layer 210 in the magnon junction 200 from reversing. However, the magnetic moment of the free magnetic layer 210 precesses due to spin transfer torque and magnon transfer torque, and a microwave oscillation signal is output from both ends of the magnon junction 200. By adjusting the magnitude of the current supplied by the current source 402, the magnitude of the magnon transfer torque (MTT) and the spin transfer torque (STT) in the magnon junction 200 can be adjusted, and therefore the frequency and amplitude of the precession of the free magnetic layer 210 in the magnon junction 200 can be adjusted, thereby controlling the frequency and amplitude of the microwave oscillation signal output at both ends of the magnon junction 200. As shown in Fig. 10, a capacitor 406 for filtering out DC components and a signal amplifier 408 for amplifying the AC signal (i.e., microwave signal) that has passed through the capacitor 406 and finally outputting the microwave signal Vout may be connected in parallel to one end of the magnon junction 200.

[0059] FIG. 11 is a schematic diagram of a magnon microwave detector (MMD) 400′ according to one embodiment of the present invention. Some of the components in the magnon microwave detector 400′ are similar to those in the magnon microwave oscillator 400, and are therefore designated by the same reference numerals and will not be described further. In the magnon microwave detector 400′, a current source 402 supplies a small detection current to the magnon junction 200. The detection current has a specific frequency and amplitude and causes little precession of the magnetic moment of the free magnetic layer 210 in the magnon junction 200. The magnetic moment of the free magnetic layer 210 of the magnon junction 200 precesses in response to an alternating electromagnetic field generated by an external microwave signal, generating a microwave oscillation signal across the magnon junction 200. The signal is filtered by a capacitor 406, amplified by a signal amplifier 408, and then supplied to a signal analysis module 410. The signal analysis module 410 may detect the frequency and amplitude of the microwave oscillation signal, and may further filter out the signal component caused by the detection current supplied by the current source 402 to obtain the detection signal component generated by the external microwave signal, and finally determine the frequency and intensity of the external microwave signal based on the dependency between the frequency and amplitude of the detection signal and the frequency and intensity of the external microwave signal. Note that only some main devices in the magnon microwave detector 400' that are closely related to the magnon junction 200 of the present invention are shown, and other parts are omitted, and other parts may be implemented with reference to microwave detectors in the prior art.

[0060] FIG. 12 is a schematic diagram of a magnon random number generator (MRNG) 500 according to one embodiment of the present invention. As shown in FIG. 12, the magnon random number generator 500 includes a magnon junction 200 and a current source 502 that applies a continuous current perpendicular to the magnon junction 200. In a conventional magnetic tunnel junction (MTJ), increasing the density of the perpendicular current applied to the MTJ reduces the barrier height between the parallel and antiparallel states of the MTJ. Therefore, if the barrier height is sufficiently small within a certain current density range, thermal perturbations cause the MTJ to randomly flip between the parallel and antiparallel states, outputting a random signal. For related principles, see JY Qin, XF Han et al., "Thermally activated magnetization back-hopping based true random number generator in nano-ring magnetic tunnel junctions." Appl. Phys. Lett. 114 (2019) 112401. Similar to a conventional magnetic tunnel junction, as the density of the perpendicular current applied to the magnon junction 200 increases, the barrier height between the parallel and antiparallel states of the magnon junction 200 also decreases. Thus, the current source 502 may supply a continuous current of a predetermined current density to the magnon junction 200 to decrease the barrier height between the parallel and antiparallel states of the magnon junction 200, realize random reversals under thermal perturbations, and output a random signal across the magnon junction 200. The random signal is amplified by the amplifier 504 and then output at the output terminal Vout.

[0061] An exemplary embodiment of the present invention further provides a magnon p-bit random number generator (MRNG), which has a similar structure to the magnon random number generator (MRNG) 500 shown in FIG. 12 , and therefore will not be described again here. As shown in FIG. 12 , by adjusting the density of the perpendicular current applied to the magnon junction 200, the magnitude of the magnon transfer torque or spin transfer torque can be adjusted, flipping the magnetic moment of the free magnetic layer 210 up or down to change the probability of parallel and antiparallel states. This realizes a probability-adjustable random number generator, i.e., it can generate random bits with a predetermined probability. Such a magnon p-bit random number generator may be applied as a core unit in artificial neural networks and algorithm construction.

[0062] One aspect of the present invention further provides an electronic device. The electronic device may include one or more of the magnon random access memory, magnon microwave oscillator, magnon microwave detector, and magnon random number generator described above. Examples of such electronic devices include, but are not limited to, mobile phones, laptop computers, desktop computers, tablet computers, media players, personal digital assistants, and wearable electronic devices.

[0063] Unless otherwise required by context, throughout this specification and claims, the terms "comprise," "include," "included," "comprise," "have," and the like, are to be construed in an inclusive sense, rather than an exclusive or exhaustive sense. In other words, they mean "including, but not limited to." Generally, as used herein, the term "connected" refers to a direct connection or the connection of two or more elements via one or more intermediate elements. Also, as used herein, the terms "herein," "above," "below," and words of similar import refer to this specification as a whole, not to any particular portion of this specification. Where the context permits, the term "or" refers to a list of two or more items, including all of the following interpretations of the term: any item in the list, all items in the list, and any combination of items in the list.

[0064] Also, unless otherwise specified or understood otherwise from the context in which it is used, conditional terms such as "can," "may," "could," "might," "for example," and "as an example" as used herein are generally intended to describe particular embodiments in which a particular embodiment does not include a particular feature, element, and / or state. Furthermore, such conditional language is not generally intended to imply that one or more embodiments require a feature, element, and / or state in any way, or that one or more embodiments must comprise logic that determines that a feature, element, and / or state is included in or performed in any particular embodiment, with or without author input or prompting.

[0065] While several embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the present disclosure. Furthermore, the novel apparatus, methods, and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and modifications may be made in the form of the methods and systems described herein without departing from the spirit of the present disclosure. Furthermore, for example, while blocks are presented in a given configuration, alternative embodiments may perform similar functions with different components and / or circuit topologies, and some blocks may be deleted, moved, added, subdivided, combined, and / or modified. Furthermore, each of these blocks may be implemented in a variety of different ways. Furthermore, any suitable combination of elements and operations of these various embodiments may be combined to provide further embodiments. Furthermore, these forms and modifications are intended to be within the scope and spirit of the present disclosure.

[0066] The foregoing description has been provided for purposes of illustration and description. It is not intended to limit embodiments of the present invention to the form disclosed herein. While the foregoing description has set forth several exemplary aspects and embodiments, those skilled in the art will recognize several variations, modifications, variations, additions, and sub-combinations.

Claims

1. A magnon junction (MJ), a first electrode layer made of a non-magnetic conductive material; a free magnetic layer formed on the first electrode layer and made of a ferromagnetic conductive material; an antiferromagnetic barrier layer formed on the free magnetic layer and made of an antiferromagnetic insulator (AFI) material; a reference magnetic layer formed on the antiferromagnetic barrier layer and made of a ferromagnetic conductive material; a second electrode layer formed on the reference magnetic layer and made of a non-magnetic conductive material; the reference magnetic layer has a perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is fixed along the perpendicular direction; the free magnetic layer has a perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is reversible along the perpendicular direction; an exchange coupling occurs at the interface between the antiferromagnetic barrier layer and the ferromagnetic conductive material, and when the magnetic moment of the free magnetic layer is reversed, the magnetic moment of the antiferromagnetic barrier layer is also reversed, thereby reducing the current density required to reverse the magnetic moment of the free magnetic layer; the first electrode layer is formed of a heavy metal non-magnetic conductive material having the spin Hall effect; the first electrode layer is configured to apply a first in-plane reversal current, the first in-plane reversal current generates a spin-polarized current that diffuses in the free magnetic layer due to the spin Hall effect, the spin-polarized current generates a spin-orbit torque (SOT) for reversing the magnetic moment of the free magnetic layer, the generated spin-polarized current diffuses to the interface of the antiferromagnetic barrier layer, thereby transferring spin angular momentum to the antiferromagnetic barrier layer and generating a magnon current, the magnon current generating a magnon transfer torque for reversing the magnetic moment of the antiferromagnetic barrier layer.

2. 2. The magnon junction according to claim 1, wherein the first electrode layer and the second electrode layer are configured to apply a perpendicular reversal current, the perpendicular reversal current being spin-polarized when flowing through the reference magnetic layer, a part of the spin-polarized current being converted into a magnon current at an interface between the reference magnetic layer and the antiferromagnetic barrier layer, the part being diffused and injected into the free magnetic layer through the antiferromagnetic barrier layer, a magnon transfer torque (MTT) being generated during the diffusion and injection, and another part of the spin-polarized current tunneling through the antiferromagnetic barrier layer to the free magnetic layer, whereby the direction of the magnetic moment of the free magnetic layer is reversed by a cooperative action of the magnon transfer torque (MTT) generated by the magnon current and the spin transfer torque (STT) generated by the spin-polarized current.

3. 3. The magnon junction according to claim 2, wherein, when the magnon current diffuses through the antiferromagnetic barrier layer, it further generates a magnon transfer torque (MTT) so that the directions of the magnetic moments aligned antiparallel to each other at the lattice points of the antiferromagnetic barrier layer are also reversed, thereby reversing both the direction of the Neel vector of the antiferromagnetic barrier layer and the direction of the magnetic moment of the free magnetic layer.

4. The first electrode layer and the second electrode layer are further configured to apply a second perpendicular reversal current, the second perpendicular reversal current being spin-polarized when flowing through the reference magnetic layer, a part of the spin-polarized current being converted into a magnon current at the interface between the reference magnetic layer and the antiferromagnetic barrier layer, diffusing and being injected into the free magnetic layer through the antiferromagnetic barrier layer, generating a magnon transfer torque (MTT), and another part of the spin-polarized current being tunneled into the free magnetic layer through the antiferromagnetic barrier layer, generating a spin transfer torque (STT) for reversing the magnetic moment direction of the free magnetic layer, thereby combining the magnon transfer torque (MTT) and the spin transfer torque (STT) generated by the second perpendicular reversal current.

2. The magnon junction according to claim 1, wherein the magnetic moment direction of the free magnetic layer is reversed by a combination of a spin-orbit torque (STT) generated by the first in-plane reversal current and a spin-orbit torque (SOT) generated by the first in-plane reversal current.

5. The ferromagnetic conductive material for forming the reference magnetic layer and the free magnetic layer is NiCo. ２ O ４ , Fe ３ GeTe ２ , VSe ２ , FePt, FePd, CoPt, CoPd, [Fe / Pt] Ｎ , [Co / Pt] Ｎ , [Fe / Pd] Ｎ , [Co / Pd] Ｎ , FeCr, CoCr, FeTb, CoTb, GdFeCo, TbFeCo, ultrathin Co—Fe—B, and Co—Fe alloy films, where N is a positive integer greater than or equal to 1; The antiferromagnetic insulating material for forming the antiferromagnetic barrier layer is Cr. ２ O ３ , CoO, NiO, FeO, MnO, MnF ２ , MnS, FeCl ２ , GdFeO ３ , NdFeO ３ , SmFeO ３ , BiCoO ３ , BiNiO ３ , LaFeO ３ [0033] 2. The magnon junction of claim 1, wherein the antiferromagnetic structure of the antiferromagnetic insulating material for forming the antiferromagnetic barrier layer is type A, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of two adjacent lattice points and opposite to the direction of the magnetic moment of another adjacent lattice point, or type B, i.e., the direction of the magnetic moment of one lattice point in the original cell is the same as the direction of the magnetic moment of one adjacent lattice point and opposite to the direction of the magnetic moment of two other adjacent lattice points, or type C, i.e., the direction of the magnetic moment of one lattice point in the original cell is opposite to the direction of the magnetic moment of three adjacent lattice points, or the antiferromagnetic barrier layer has a spiral magnetic structure.

6. The heavy metal non-magnetic conductive material for forming the first electrode layer is Pt, W, Ta, Pd, Ir, W, Bi, Mo, Pb, Hf, Ru, IrMn, PtMn, AuMn, Bi ２ Se ３ , Bi ２ Te ３ 10. The magnon junction of claim 1, comprising one or more of:

7. 1. A method of operating a magnon junction, comprising: The magnon junction is a first electrode layer made of a non-magnetic conductive material; a free magnetic layer formed on the first electrode layer and made of a ferromagnetic conductive material; an antiferromagnetic barrier layer formed on the free magnetic layer and made of an antiferromagnetic insulating material; a reference magnetic layer formed on the antiferromagnetic barrier layer and made of a ferromagnetic conductive material; a second electrode layer formed on the reference magnetic layer and made of a non-magnetic conductive material; the reference magnetic layer has a perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is fixed along the perpendicular direction; the free magnetic layer has a perpendicular magnetic anisotropy or a perpendicular magnetic moment component, and the magnetic moment direction is reversible along the perpendicular direction; the antiferromagnetic barrier layer has a perpendicular magnetic anisotropy or a perpendicular magnetic moment component, an exchange coupling occurs at the interface between the antiferromagnetic barrier layer and the ferromagnetic conductive material, and when the magnetic moment of the free magnetic layer is reversed, the magnetic moment of the antiferromagnetic barrier layer is also reversed, thereby reducing the current density required to reverse the magnetic moment of the free magnetic layer; the first electrode layer is formed of a heavy metal non-magnetic conductive material having the spin Hall effect; the first electrode layer is configured to apply a first in-plane reversal current, the first in-plane reversal current generating a spin-polarized current that diffuses in the free magnetic layer due to the spin Hall effect, the spin-polarized current generating a spin-orbit torque (SOT) for reversing the magnetic moment of the free magnetic layer, the generated spin-polarized current diffusing to the interface of the antiferromagnetic barrier layer to transfer spin angular momentum to the antiferromagnetic barrier layer to generate a magnon current, the magnon current generating a magnon transfer torque for reversing the magnetic moment of the antiferromagnetic barrier layer, The method for operating the magnon junction includes: applying a perpendicular switching current that flows perpendicularly through the magnon junction using the first electrode layer and the second electrode layer, the perpendicular switching current being spin-polarized when flowing through the reference magnetic layer; converting a portion of the spin-polarized current into a magnon current at an interface between the reference magnetic layer and the antiferromagnetic barrier layer, and diffusing and injecting the magnon current into the free magnetic layer through the antiferromagnetic barrier layer, wherein a magnon transfer torque (MTT) is generated during the diffusion and injection; and tunneling another portion of the spin-polarized current tunnels through the antiferromagnetic barrier layer to the free magnetic layer, thereby reversing the magnetic moment direction of the free magnetic layer due to the combined action of a magnon transfer torque (MTT) generated by the magnon current and a spin transfer torque (STT) generated by the spin-polarized current.

8. the first electrode layer is formed of a heavy metal non-magnetic conductive material having the spin Hall effect; The method comprises:

8. The method of claim 7, further comprising: applying an in-plane reversal current through the first electrode layer, the in-plane reversal current generating a spin-polarized current that diffuses in the free magnetic layer due to the spin Hall effect, the spin-polarized current generating a spin-orbit torque (SOT) for reversing the magnetic moment of the free magnetic layer, whereby a magnon transfer torque (MTT) and a spin transfer torque (STT) generated by the perpendicular reversal current cooperate with the spin-orbit torque (SOT) generated by the in-plane reversal current to reverse the direction of the magnetic moment of the free magnetic layer.

9. 9. The method of claim 8, wherein the magnon flow further generates a magnon transfer torque (MTT) such that the directions of magnetic moments aligned antiparallel to each other at different lattice points of the antiferromagnetic barrier layer are also reversed, thereby reversing both the Neel vector direction of the antiferromagnetic barrier layer and the magnetic moment direction of the free magnetic layer.

10. 10. A magnon random access memory (mRAM) comprising an array of a plurality of magnon storage units, each magnon storage unit comprising a magnon junction according to claim 1.

11. The magnon junction according to claim 1; a current source that applies a current that flows perpendicularly through the magnon junction to generate a microwave oscillation signal across the magnon junction; The magnitude of the current provided by the current source is adjustable to adjust the magnitude of the magnon transfer torque and spin transfer torque (MTT+STT) in the magnon junction to adjust the frequency and amplitude of the precession of the magnetic moment of the free magnetic layer in the magnon junction, thereby controlling the frequency and amplitude of the microwave oscillation signal output by both ends of the magnon junction.

12. 2. The magnon junction according to claim 1, wherein a magnetic moment of the magnon junction precesses in response to an alternating electromagnetic field generated by an external microwave signal; a current source for applying a detection current perpendicularly through the magnon junction to generate a microwave oscillation signal across the magnon junction, the frequency and amplitude of the microwave oscillation signal depending on the frequency and intensity of the external microwave signal, respectively; a signal analysis module that detects the frequency and amplitude of the microwave oscillation signal to determine the frequency and intensity of the external microwave signal.

13. The magnon junction according to claim 1; a current source that applies a continuous current that flows perpendicularly through the magnon junction, the continuous current having a predetermined current density so as to reduce the barrier height between the parallel and antiparallel states of the magnon junction, realize random reversals upon thermal perturbation, and output a random signal across the magnon junction; and a magnon random number generator (MRNG).

14. The magnon junction according to claim 1; a current source that applies a continuous current that flows perpendicularly through the magnon junction, the continuous current having a predetermined current density so as to reduce the barrier height between the parallel and antiparallel states of the magnon junction, realize random reversals under thermal perturbations, and output random signals at both ends of the magnon junction; and a magnon p-bit Random Number Generator (MRNG), wherein the magnitude of the continuous current is adjusted to adjust the magnitude of the magnon transfer torque or spin transfer torque, thereby changing the probability of generating the parallel and antiparallel states and realizing a probability-adjustable random number generator.

15. The magnon random access memory according to claim 10 . The magnon microwave oscillator according to claim 11 , 13. The magnon microwave detector according to claim 12 . The magnon random number generator of claim 13, and 15. An electronic device comprising at least one of the magnon stochastic bit random number generators of claim 14.

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