Chiral / magnetic heterojunction device of exchange bias effect and preparation method thereof

Abstract

The application belongs to the field of spin electronics and information technology, and provides a chiral / magnetic heterojunction device with exchange bias effect and a preparation method thereof, which comprises a substrate, a ferromagnetic material layer and a chiral material layer, and the ferromagnetic material layer and the chiral material layer are directly contacted and stacked and then placed above the substrate. Different chiral configurations of the chiral material layer correspond to different polarities of the exchange bias effect. The realization of the exchange bias effect is not limited by the types and preparation sequences of the ferromagnetic material layer and the chiral material layer, and through selection of chiral material layers with different configurations, the customized regulation and control of the polarity of the exchange bias effect can be realized, thereby providing a novel and feasible technical approach for realizing high-stability exchange bias effect.

Description

Technical Field

[0001] This invention belongs to the field of spintronics and information technology, and particularly relates to chiral / magnetic heterojunction devices with exchange bias effect and their fabrication methods. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The exchange bias (EB) effect refers to the phenomenon in magnetic heterostructures with interfacial coupling where the hysteresis loop of a ferromagnetic material undergoes a unidirectional displacement relative to zero magnetic field. Since its discovery in 1956, this effect has become one of the core physical mechanisms of magnetic random access memory, magnetic sensors, and novel spin logic devices. Current theories generally agree that the EB effect originates from the exchange interaction at the antiferromagnetic / ferromagnetic (AFM / FM) interface, with the "pinning" effect of the uncompensated magnetic moment of the AFM on the FM spin being its main physical basis. The stable occurrence of the EB effect typically requires the following conditions: the AFM material possesses sufficient magnetic anisotropy to resist magnetic moment reversals induced by external fields and thermal fluctuations; and the AFM material has an uncompensated magnetic moment at the interface. Key parameters of the EB effect are known, such as the bias field. and cutoff temperature The specific parameters depend primarily on factors such as the material's crystal structure, magnetic anisotropy, magnetic domain characteristics, and the quality of the AFM / FM interface.

[0004] Numerous experimental and theoretical studies have demonstrated that the EB effect can be achieved through interface engineering in various heterostructures. In traditional three-dimensional thin film systems, researchers have already demonstrated this effect in materials such as IrMn / Co and La... 0.3 Sr 0.7 The Eppendorf (EB) effect has been observed in heterostructures such as FeO3 / SrRuO3, IrMn / NiFe, Gd / MnPt, and CoFe2O4 / Cr2O3. With the rise of two-dimensional materials, 2D magnetic materials, due to their atomic-level thickness, absence of surface dangling bonds, and weak interlayer van der Waals (vdW) interactions, provide an ideal platform for constructing atomically sharp interfaces with extremely low defect densities, thus becoming a frontier direction in EB research. Currently, researchers have observed significant EB effects in vdW heterostructures such as CrCl3 / Fe3GeTe2, CrPS4 / Fe3GeTe2, CrOCl / Fe3GeTe2, MnPX3 / Fe3GeTe2 (X=S, Se), FePS3 / Fe5GeTe2, and FePS3 / Fe3GaTe2. However, existing EB effects are mainly limited to the single combination of "AFM / FM" and have not yet been effectively extended to more diverse interfacial coupling mechanisms. Summary of the Invention

[0005] To address at least one of the technical problems mentioned above, this invention provides a chiral / magnetic heterojunction device with exchange bias effect and its fabrication method. This breaks through the traditional AFM / FM paradigm, constructs an exchange bias structure with a novel coupling mechanism, and realizes the construction of a new functional unit with higher thermal stability and process compatibility.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A first aspect of the present invention provides a chiral / magnetic heterojunction device with exchange bias effect, comprising a substrate, a ferromagnetic material layer and a chiral material layer, wherein the ferromagnetic material layer and the chiral material layer are stacked in direct contact and placed on top of the substrate.

[0007] Furthermore, the stacking method of the ferromagnetic material layer and the chiral material layer includes: the ferromagnetic material layer is located between the chiral material layer and the substrate; Alternatively, the chiral material layer may be located between the ferromagnetic material layer and the substrate.

[0008] Furthermore, the device also includes an insulating layer that covers a ferromagnetic material layer and a chiral material layer.

[0009] Furthermore, the ferromagnetic material layer is a three-dimensional ferromagnetic thin film or a two-dimensional ferromagnetic material.

[0010] Furthermore, the chiral material layer may employ organic chiral materials, inorganic chiral materials, or a hybrid of organic and inorganic chiral materials.

[0011] Furthermore, different chiral configurations of the chiral material layer correspond to different exchange bias effect polarities.

[0012] A second aspect of the present invention provides a method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, comprising the following steps: A ferromagnetic material layer is prepared on a substrate; A chiral material layer is prepared on a ferromagnetic material layer, wherein the ferromagnetic material layer and the chiral material layer are in direct contact.

[0013] Furthermore, ferromagnetic material layers and chiral material layers are prepared in a vacuum or inert gas environment to form a direct contact interface.

[0014] A third aspect of the present invention provides a method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, comprising the following steps: Prepare a chiral material layer on a substrate; A ferromagnetic material layer is prepared on a chiral material layer, wherein the ferromagnetic material layer is in direct contact with the chiral material layer.

[0015] Furthermore, during the preparation of the chiral material layer and the ferromagnetic material layer, the chiral material layer and the ferromagnetic material layer must not be exposed to air in order to form a direct contact interface.

[0016] A fourth aspect of the present invention provides a spintronic device comprising a chiral / magnetic heterojunction device with exchange bias effect as described in the first aspect.

[0017] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention proposes a chiral / magnetic heterojunction device with exchange bias effect. The realization of the exchange bias effect is not limited by the type and preparation order of the ferromagnetic material layer and the chiral material layer. By selecting chiral materials with different configurations (such as right-handed molecules or left-handed molecules), the polarity of the exchange bias effect can be customized.

[0018] 2. This invention proposes a method for fabricating chiral / magnetic heterostructures with exchange bias effects. Unlike traditional methods that rely on AFM / FM heterostructures to generate exchange bias effects, the proposed method, based on chiral / ferromagnetic heterostructures, is simpler and more flexible, and can be implemented using various mature physical or chemical deposition processes. This not only ensures the operability of the structural design and process compatibility but also provides a practical technical approach for the development and realization of novel spintronic devices.

[0019] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0021] Figure 1 This is a schematic diagram of a chiral / magnetic heterojunction device with exchange bias effect provided in an embodiment of the present invention; Figure 2 This is the LaF3 / L(D)-PEN / Fe3GaTe2 / SiO2 / Si heterostructure provided in the embodiments of the present invention; Figure 3 This is a schematic diagram of another chiral / magnetic heterojunction device with exchange bias effect provided in an embodiment of the present invention; Figure 4 The test results (anomalous Hall resistance) of the left-handed material layer / ferromagnetic material layer (L-PEN / Fe3GaTe2) provided in the embodiments of the present invention are as follows: Figure 5The results (anomalous Hall resistance) are the test results of the right-handed material layer / ferromagnetic material layer (D-PEN / Fe3GaTe2) provided in the embodiments of the present invention. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] In this invention, terms such as "upper," "lower," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are merely relational terms determined for the convenience of describing the structural relationship of the various components or elements of this invention, and do not specifically refer to any component or element in this invention, and should not be construed as limiting this invention.

[0026] In this invention, terms such as "fixed connection," "connected," and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0027] This invention provides a chiral / magnetic heterojunction device with exchange bias effect, comprising a substrate, a ferromagnetic material layer, and a chiral material layer, wherein the ferromagnetic material layer and the chiral material layer are stacked in direct contact and placed on top of the substrate. The technical solution proposed in this invention is independent of the stacking order and material type of the ferromagnetic and chiral material layers, and is not strictly limited by specific fabrication process conditions. Stable exchange bias effect can be achieved as long as the basic direct contact relationship is satisfied.

[0028] like Figure 1 As shown, as an embodiment of the present invention, this embodiment provides a chiral / magnetic heterojunction device with exchange bias effect, the structure comprising a substrate, a ferromagnetic material layer and a chiral material layer arranged sequentially from bottom to top.

[0029] Specifically, the ferromagnetic material layer includes two-dimensional ferromagnetic materials or three-dimensional ferromagnetic thin films; among which, two-dimensional ferromagnetic materials include Fe3GaTe2, Fe3GeTe2, Fe5GeTe2 or Cr2Ge2Te6, etc., and three-dimensional ferromagnetic thin films include Fe, Co, Ni, CoFeB and their alloys, etc.

[0030] Specifically, the chiral material layer includes, but is not limited to, organic chiral materials, inorganic chiral materials, or organic-inorganic hybrid chiral materials; Among them, organic chiral materials include chiral small molecules (D-penicillamine (D-PEN) and L-penicillamine (L-PEN), R-2,2′-dimethoxy-1,1′-binaphthyl (R-BINAP) and S-2,2′-dimethoxy-1,1′-binaphthyl (S-BINAP), etc.), amino acids, peptides and sugars, etc. Inorganic chiral materials include chiral perovskites, chiral metal nanoparticles, and chiral semiconductor quantum dots; Organic-inorganic hybrid chiral materials, such as two-dimensional materials with chiral molecular intercalation, chiral metal-organic frameworks (MOFs), and chiral covalent organic frameworks (COFs).

[0031] The chiral / magnetic heterojunction device with exchange bias effect provided in this embodiment also includes an insulating protective layer. The insulating protective layer coats the ferromagnetic material layer and the chiral molecular layer to isolate oxygen, moisture, and other substances in the air, achieving effective isolation from the external environment and improving structural stability. The insulating protective layer includes insulating films such as LaF3, Al2O3, and Sb2O3.

[0032] like Figure 2 As shown, a specific combination structure is illustrated in one manner, in which a chiral material layer is stacked on a ferromagnetic material layer, wherein the substrate is SiO2 / Si, the two-dimensional ferromagnetic material layer is Fe3GaTe2, the chiral material layer is left-chilled L-penicillamine (L-PEN) or right-chilled D-penicillamine (D-PEN), and the insulating protective layer is LaF3, thereby forming a LaF3 / L(D)-PEN / Fe3GaTe2 / SiO2 / Si heterojunction structure.

[0033] The chiral material layer L(D)-PEN is directly deposited on the surface of the ferromagnetic material layer Fe3GaTe2 and forms direct contact with it; the insulating protective layer LaF3 covers the L(D)-PEN / Fe3GaTe2 heterojunction, realizing full coverage and encapsulation of the heterojunction, thereby effectively inhibiting the erosion of oxygen and moisture and improving the environmental stability of the system.

[0034] Furthermore, the thicknesses of the insulating protective layer LaF3, the chiral material layer L(D)-PEN, and the two-dimensional ferromagnetic material layer Fe3GaTe2 are not limited. When they are all in the nanometer range, the heterostructure can still exhibit the exchange bias effect.

[0035] It should be noted that the specific thickness of each layer can be flexibly adjusted within a certain range to meet the requirements of different device structures and process conditions. The thickness described here is only an example and does not constitute a limitation.

[0036] like Figure 3 As shown, as another embodiment of the present invention, this embodiment provides a chiral / magnetic heterojunction device with exchange bias effect, the structure including a substrate, a chiral material layer and a ferromagnetic material layer arranged sequentially from bottom to top.

[0037] Specifically, the ferromagnetic material layer includes two-dimensional ferromagnetic materials or three-dimensional ferromagnetic thin films; among which, two-dimensional ferromagnetic materials include Fe3GaTe2, Fe3GeTe2, Fe5GeTe2 or Cr2Ge2Te6, etc., and three-dimensional ferromagnetic thin films include Fe, Co, Ni, CoFeB and their alloys, etc.

[0038] Specifically, the chiral material layer includes, but is not limited to, organic chiral materials, inorganic chiral materials, or organic-inorganic hybrid chiral materials; Among them, organic chiral materials include chiral small molecules (D-penicillamine (D-PEN) and L-penicillamine (L-PEN), R-2,2′-dimethoxy-1,1′-binaphthyl (R-BINAP) and S-2,2′-dimethoxy-1,1′-binaphthyl (S-BINAP), etc.), amino acids, peptides and sugars, etc. Inorganic chiral materials include chiral perovskites, chiral metal nanoparticles, and chiral semiconductor quantum dots; Organic-inorganic hybrid chiral materials, such as two-dimensional materials with chiral molecular intercalation, chiral metal-organic frameworks (MOFs), and chiral covalent organic frameworks (COFs).

[0039] Furthermore, the chiral / magnetic heterojunction device with exchange bias effect provided in this embodiment also includes an insulating protective layer. The insulating protective layer coats the ferromagnetic material layer and the chiral molecular layer to isolate oxygen, moisture, and other substances in the air, thereby improving structural stability. The insulating protective layer includes insulating films such as LaF3, Al2O3, and Sb2O3.

[0040] Furthermore, the thicknesses of the insulating protective layer LaF3, the chiral material layer L(D)-PEN, and the two-dimensional ferromagnetic material layer Fe3GaTe2 are not limited. When they are all in the nanometer range, the heterostructure can still exhibit the exchange bias effect.

[0041] It should be noted that the specific thickness of each layer can be flexibly adjusted within a certain range to meet the requirements of different device structures and process conditions. The thickness described here is only an example and does not constitute a limitation.

[0042] It should be noted that the specific implementation process in this embodiment is similar to the specific implementation method of the above embodiment. Please refer to the description in the above embodiment section for details. In order to reduce redundancy, it will not be repeated here.

[0043] The exchange bias effect proposed in this invention is not limited by the type or preparation order of the ferromagnetic and chiral material layers. By selecting chiral materials with different configurations (such as left-handed or right-handed molecules), the polarity of the exchange bias effect can be customized.

[0044] As another embodiment of the present invention, combined with Figure 1 Regarding the structure in the example, this embodiment provides a method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, including the following steps: Step 1: Prepare a ferromagnetic material layer on the substrate; The ferromagnetic material layer can be a three-dimensional ferromagnetic thin film or a two-dimensional ferromagnetic material. The ferromagnetic material layer can be prepared by suitable methods such as molecular beam epitaxy (MBE), magnetron sputtering (MS), pulsed laser deposition (PLD), chemical vapor deposition (CVD), physical vapor deposition (PVD), chemical vapor transport (CVT), spin coating, and mechanical exfoliation. The substrate is selected according to experimental requirements and interface matching conditions.

[0045] In a specific embodiment, with Figure 2 Taking the LaF3 / L(D)-PEN / Fe3GaTe2 / SiO2 / Si heterojunction as an example, a two-dimensional ferromagnetic Fe3GaTe2 thin layer was first obtained by mechanical exfoliation in a glove box under inert gas protection. Subsequently, the thickness of the obtained thin layer was characterized using optical microscopy and atomic force microscopy. Next, a dry transfer process was used to position and transfer the target Fe3GaTe2 thin layer onto the final SiO2 / Si substrate, which was pre-fabricated with Hall-bar electrodes using micro / nano fabrication processes for subsequent exchange bias effect electrical transport testing.

[0046] Step 2: Prepare a chiral material layer on the ferromagnetic material layer; The chiral material layer includes, but is not limited to, organic chiral materials, inorganic chiral materials, or organic-inorganic hybrid chiral materials, and can be prepared by suitable methods such as thermal evaporation, self-assembly, mechanical exfoliation, spin coating, and chemical vapor deposition (CVD).

[0047] In this embodiment, a ferromagnetic material layer and a chiral material layer are prepared in a vacuum or inert gas environment to form a direct contact interface; In the L(D)-PEN / Fe3GaTe2 heterojunction of the specific embodiment, chiral small molecules L(D)-PEN are deposited on the surface of two-dimensional ferromagnetic material Fe3GaTe2 by thermal evaporation to form a direct contact interface.

[0048] The chiral material layer and the magnetic material layer must be in direct contact to ensure a high-quality interface. In the specific embodiment of the L(D)-PEN / Fe3GaTe2 heterojunction, the thermal evaporation chamber is directly connected to the glove box, thereby ensuring that the sample is never exposed to the atmospheric environment during transfer and deposition.

[0049] Furthermore, the fabrication method of the chiral / magnetic heterojunction device with exchange bias effect provided in this embodiment also includes the following steps: Step 3: Prepare the insulating protective layer; Insulating protective layers, such as thin films of LaF3, Al2O3, and Sb2O3, can be prepared by epitaxial growth techniques such as atomic layer deposition (ALD) and thermal evaporation, as well as other suitable methods such as spin coating.

[0050] In the specific embodiment of the LaF3 / L(D)-PEN / Fe3GaTe2 / SiO2 / Si heterojunction, a LaF3 thin film is used to cover the heterojunction to isolate it from the erosion of oxygen and moisture, thereby improving the system stability. Here, the LaF3 is deposited as a protective layer using a thermal evaporation system interconnected with the glove box to achieve process continuity and structural stability.

[0051] As another embodiment of the present invention, combined with Figure 3 Regarding the structure in the example, this embodiment provides a method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, including the following steps: Step 1: Prepare a chiral material layer on the substrate; The chiral material layer includes, but is not limited to, organic chiral materials, inorganic chiral materials, or organic-inorganic hybrid chiral materials, and can be prepared by suitable methods such as thermal evaporation, self-assembly, mechanical exfoliation, spin coating, and chemical vapor deposition (CVD).

[0052] Step 2: Prepare a ferromagnetic material layer on the chiral material layer; The ferromagnetic material layer can be a three-dimensional ferromagnetic thin film or a two-dimensional ferromagnetic material. The ferromagnetic material layer can be prepared by suitable methods such as molecular beam epitaxy (MBE), magnetron sputtering (MS), pulsed laser deposition (PLD), chemical vapor deposition (CVD), physical vapor deposition (PVD), chemical vapor transport (CVT), spin coating, and mechanical exfoliation.

[0053] The chiral material layer and the magnetic material layer must be in direct contact, ensuring a high-quality interface. The preparation sequence and method of the chiral material layer and the ferromagnetic material layer need to be selected according to the characteristics of the heterostructure being prepared, and this invention does not impose any restrictions.

[0054] Furthermore, the fabrication method of the chiral / magnetic heterojunction device with exchange bias effect provided in this embodiment also includes the following steps: Step 3: Prepare the insulating protective layer; Insulating protective layers, such as thin films of LaF3, Al2O3, and Sb2O3, can be prepared by suitable methods such as atomic layer deposition (ALD), epitaxial growth techniques such as thermal evaporation, and spin coating.

[0055] Experimental Test In classic AFM / FM exchange bias effect systems, the sample is typically heated to above the Nell temperature of the antiferromagnetic material, and then cooled by an external magnetic field at this temperature (μ0). H cool (Can be zero) to establish unidirectional exchange anisotropy at the interface. Subsequently, the sample is cooled to the target test temperature, and the anomalous Hall resistance of the ferromagnetic material is measured. Exchange bias field ( H EB The exchange bias effect is a key parameter for measuring its polarity and intensity, and its calculation formula is as follows: ： ,in and These represent positive and negative coercive fields, respectively. H EB The temperature at which the EB effect disappears is the cutoff temperature. T b In chiral / magnetic heterojunctions, the temperature is typically raised to above the Curie temperature of the ferromagnetic material layer, and an external magnetic field can be applied at this temperature. After cooling to the target test temperature, the magnetic properties of the ferromagnetic material layer are tested to characterize its exchange bias effect. Alternatively, without applying an external magnetic field, after cooling to the target test temperature, a large external magnetic field (pre-magnetic field) is applied beforehand, and then the magnetic properties of the ferromagnetic material layer are tested to characterize its exchange bias effect.

[0056] In this invention, taking the L(D)-PEN / Fe3GaTe2 heterojunction as an example, the temperature is generally first raised to above the Curie temperature of the ferromagnetic material layer, and an external magnetic field (μ0) can be applied at this temperature. H cool (The value can be zero), then cooled to the target test temperature, the anomalous Hall resistance of the ferromagnetic material layer is measured to characterize its exchange bias effect. Details are as follows: In the L(D)-PEN / Fe3GaTe2 heterojunction example, its exchange bias effect was tested using an electrical method. First, the sample was heated to above room temperature, an external magnetic field was applied, and then it was cooled to the target test temperature. At the test temperature, a constant current was applied to the heterojunction through two current-carrying electrodes, and the Hall voltage was measured through an output electrode perpendicular to the current direction, and the Hall resistance was calculated. Further, by linearly fitting the Hall resistance data in the high-field range and subtracting the ordinary Hall effect component, the anomalous Hall resistance (…) was obtained. R xy ).

[0057] The detection of the exchange bias effect in chiral / magnetic heterojunctions is not limited to anomalous Hall resistance testing. In heterojunctions formed by different types of chiral and ferromagnetic materials, appropriate testing methods can be selected based on the specific structural characteristics and requirements of the heterojunction. For example, the exchange bias effect can be characterized using magneto-optical Kerr effect (MOKE) and magnetic circular dichroism (MCD). The electrical testing method described in this embodiment is merely illustrative and not intended to limit the technical solution of this invention.

[0058] In left-handed L-PEN / Fe3GaTe2 heterojunctions, refer to the appendix. Figure 4 Applying μ0 at 300 K H cool = When an external magnetic field of 1 T is applied and then reduced to 5 K, the heterojunction exhibits a significant positive exchange bias effect (under the condition of applying a positive cooling field). H EB >0), its exchange bias field is 560 Oe. In the right-handed D-PEN / Fe3GaTe2 heterojunction, refer to the appendix. Figure 5 Applying μ0 at 300 K H cool = When an external magnetic field of 1 T is applied and then reduced to 5 K, the heterojunction exhibits a significant negative exchange bias effect (under the condition of applying a positive cooling field). H EB <0, its exchange bias field is -2745 Oe. It is worth noting that the above exchange bias field value is only an experimental example, and can be further optimized by changing the thickness of Fe3GaTe2 and L(D)-PEN to achieve a larger exchange bias field.

[0059] By selecting chiral material layers with different chiral configurations (left-handed or right-handed), the polarity of the exchange bias effect in chiral material layer / ferromagnetic material layer heterojunctions can be controlled. The left-handed L-PEN / Fe3GaTe2 heterojunction exhibits a positive exchange bias, while the right-handed D-PEN / Fe3GaTe2 heterojunction exhibits a negative exchange bias. It should be understood that the phenomena described in this invention are not limited to chiral molecular systems; the exchange bias effect can also be observed when other chiral materials with left-handed or right-handed configurations are combined with ferromagnetic materials.

[0060] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A chiral / magnetic heterojunction device with exchange bias effect, characterized in that, It includes a substrate, a ferromagnetic material layer, and a chiral material layer, with the ferromagnetic material layer and the chiral material layer stacked in direct contact and placed on top of the substrate.

2. The chiral / magnetic heterojunction device with exchange bias effect as described in claim 1, characterized in that, The stacking method of the ferromagnetic material layer and the chiral material layer includes: the ferromagnetic material layer is located between the chiral material layer and the substrate; Alternatively, the chiral material layer may be located between the ferromagnetic material layer and the substrate.

3. The chiral / magnetic heterojunction device with exchange bias effect as described in claim 1, characterized in that... The device also includes an insulating protective layer, which covers a ferromagnetic material layer and a chiral material layer.

4. The chiral / magnetic heterojunction device with exchange bias effect as described in claim 1, characterized in that, The ferromagnetic material layer is a three-dimensional ferromagnetic thin film or a two-dimensional ferromagnetic material.

5. The chiral / magnetic heterojunction device with exchange bias effect as described in claim 1, characterized in that, The chiral material layer can be made of organic chiral material, inorganic chiral material, or a hybrid chiral material of organic and inorganic materials.

6. The chiral / magnetic heterojunction device with exchange bias effect as described in claim 1, characterized in that, Different chiral configurations of chiral material layers correspond to different exchange bias effect polarities.

7. A method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, characterized in that, Includes the following steps: A ferromagnetic material layer is prepared on a substrate; A chiral material layer is prepared on a ferromagnetic material layer, wherein the ferromagnetic material layer and the chiral material layer are in direct contact.

8. The method for fabricating a chiral / magnetic heterojunction device with exchange bias effect as described in claim 7, characterized in that, Ferromagnetic and chiral material layers are prepared in a vacuum or inert gas environment to form a direct contact interface.

9. A method for fabricating a chiral / magnetic heterojunction device with exchange bias effect, characterized in that, Includes the following steps: Prepare a chiral material layer on a substrate; A ferromagnetic material layer is prepared on a chiral material layer, wherein the ferromagnetic material layer is in direct contact with the chiral material layer.

10. A spintronic device, characterized in that, Including chiral / magnetic heterojunction devices with exchange bias effect as described in any one of claims 1-6.

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