A magnetic spin valve, a magnetic superconducting memory cell and a method of manufacturing the same

Abstract

This invention provides a magnetic spin valve, a magnetic superconducting memory cell, and their fabrication method, belonging to the field of superconducting spintronics technology. The magnetic spin valve of this invention includes a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a second ferromagnetic layer, and a third superconducting layer stacked sequentially. By changing the parallel or antiparallel magnetization alignment of the first and second ferromagnetic layers, the resulting magnetic exchange effect causes the superconducting transition temperature T of the second superconducting layer to change. c The change causes the second superconducting layer to switch between superconducting and non-superconducting states, modulating the Josephson coupling of the entire device, and ultimately achieving the control of the superconducting critical current I. c Amplitude modulation enables the storage of "0" and "1". The magnetic spin valve proposed in this invention innovatively combines a superconducting spin valve and a magnetic Josephson junction, achieving this by changing the critical superconducting current I. c This enables complete switching of critical superconducting current to increase the storage window, providing a solution for optimizing the overall performance of cryogenic memories.

Description

Technical Field

[0001] This invention relates to the field of superconducting spintronics technology, and in particular to a magnetic spin valve, a magnetic superconducting storage cell, and a method for fabricating the same. Background Technology

[0002] As the feature size of integrated circuits continues to shrink, it has become clear that standard CMOS-based memories are reaching their limits, determined by power requirements and heat dissipation. Large-scale computing devices and data centers already consume several percentage points of the world's electricity production, and this proportion is expected to increase significantly in the coming decades. Superconducting memories have become crucial for solving energy problems. Currently, my country is developing a superconducting computer research and development project. Low-temperature superconducting memories not only contribute to the research and development of superconducting computers but also facilitate the construction of complete hardware systems under quantum computing architectures.

[0003] The basic working unit of a magnetic superconducting memory is a magnetic superconducting heterojunction, typically a sandwich structure of a ferromagnetic layer / superconducting layer / ferromagnetic layer (F / SC / F). In this system, one ferromagnetic layer serves as the reference layer, its magnetization direction generally fixed by coupling with a nearby antiferromagnetic layer. The other layer is a free layer, its magnetization direction arbitrarily changed by the external magnetic field. When the magnetizations of the two ferromagnetic layers are parallel, the ferromagnetic intensity experienced by the intermediate superconductor is relatively large, resulting in a larger average exchange field acting on the intermediate superconducting layer and a stronger disruptive effect on the superconducting Cooper pairs. Therefore, the superconducting transition temperature T0 is higher. c The superconducting transition temperature T is relatively low; conversely, it is lower when the elements are antiparallel. c The resistance is relatively high. Therefore, we can adjust the state of the intermediate superconducting layer by controlling the relative alignment of the magnetization directions of the reference layer and the free layer. We can utilize the high and low resistance states of the entire system formed when the magnetization is parallel or antiparallel to store "1" and "0" in binary. To avoid writing errors, the superconducting transition temperature difference ΔT between parallel and antiparallel alignments should be minimized. c The value is large, but in the superconducting spin valve composed of 3d magnetic transition metal used in the experiment, ΔT c Since the memory capacity is only in the mK range, the development of magnetic superconducting memories still suffers from drawbacks such as high write error rates and low memory windows.

[0004] For memory structures with superconducting / ferromagnetic / superconducting layers, the resulting magnetic exchange interactions can modulate the Josephson coupling at the superconducting / ferromagnetic interface, thereby altering the critical superconducting current I of the magnetic Josephson junction. c I c It will produce periodic changes in amplitude and phase when the thickness of the ferromagnetic layer changes. It can be read by means of electrical transport measurement or phase-sensitive measurement. This magnetoelectric transport control method can also be used to construct a magnetically controlled electronic reading storage unit.

[0005] Currently, the construction of magnetic superconducting spin memory faces challenges related to the superconducting critical current I. c However, current magnetic superconducting spin memories suffer from limitations such as limited controllability and a short storage window. Given these shortcomings, improvements are necessary. Summary of the Invention

[0006] In view of this, the present invention proposes a magnetic spin valve, a magnetic superconducting storage unit and its preparation method, in order to solve or partially solve the problems existing in the prior art.

[0007] In a first aspect, the present invention provides a magnetic spin valve, comprising:

[0008] First superconducting layer;

[0009] The first ferromagnetic layer is located on one side of the first superconducting layer;

[0010] The second superconducting layer is located on the side of the first ferromagnetic layer away from the first superconducting layer;

[0011] The second ferromagnetic layer is located on the side of the second superconducting layer away from the first superconducting layer;

[0012] The third superconducting layer is located on the side of the second ferromagnetic layer away from the first superconducting layer;

[0013] The first ferromagnetic layer and the second ferromagnetic layer may be made of different materials, or the first ferromagnetic layer and the second ferromagnetic layer may be made of the same material but have different thicknesses.

[0014] Preferably, the materials used for the first ferromagnetic layer and the second ferromagnetic layer of the magnetic spin valve include any one of the following: magnetic transition metal materials, in-plane or perpendicular magnetic anisotropic ferromagnetic materials, rare earth metal materials, and materials containing rare earth elements.

[0015] Preferably, in the magnetic spin valve, the magnetic transition metal material includes any one of iron, cobalt, and nickel.

[0016] Preferably, in the magnetic spin valve, the in-plane or perpendicular magnetic anisotropic ferromagnetic material includes any one of nickel-iron alloy, cobalt-iron-boron alloy, and cobalt-platinum alloy.

[0017] The rare earth metal material includes any one of europium, gadolinium, holmium, dysprosium, and gadolinium-dysprosium alloy;

[0018] The rare earth element-containing material includes any one of europium sulfide, gadolinium nitride, holmium nitride, dysprosium nitride, dysprosium sulfide, gadolinium sulfide, and holmium sulfide.

[0019] Preferably, in the magnetic spin valve, the second superconducting layer is made of a different material than the first or third superconducting layer, or the second superconducting layer is made of the same material as the first or third superconducting layer but with different thicknesses.

[0020] Preferably, the materials used for the second superconducting layer, the first superconducting layer, and the third superconducting layer of the magnetic spin valve include any one of niobium, niobium-titanium alloy, niobium-tin alloy, and vanadium-germanium.

[0021] Secondly, the present invention also provides a magnetic superconducting storage cell, including the aforementioned magnetic spin valve.

[0022] Preferably, the magnetic superconducting memory cell further includes a substrate and a top electrode, wherein the first superconducting layer is located on one side of the substrate, and the top electrode is located on the side of the third superconducting layer away from the first superconducting layer.

[0023] Preferably, in the magnetic superconducting memory cell, the substrate includes at least one of a single-crystal silicon wafer substrate, a single-crystal sapphire substrate, and a single-crystal magnesium oxide substrate;

[0024] The top electrode is made of a superconducting metallic material.

[0025] Thirdly, the present invention also provides a method for preparing the aforementioned magnetic superconducting memory cell, comprising the following steps:

[0026] A magnetic superconducting memory cell is obtained by sequentially depositing a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a second ferromagnetic layer, a third superconducting layer, and a top electrode on a substrate.

[0027] The magnetic spin valve and magnetic superconducting storage unit of the present invention have the following technical advantages over the prior art:

[0028] The magnetic spin valve of the present invention comprises a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a second ferromagnetic layer, and a third superconducting layer stacked sequentially. The first and second ferromagnetic layers are made of different materials or are made of the same material but with different thicknesses, to ensure that the first and second ferromagnetic layers have different coercivities, enabling parallel and antiparallel state transitions. The magnetic spin valve of the present invention, by changing the parallel or antiparallel magnetization arrangement of the first and second ferromagnetic layers, generates a magnetic exchange effect that causes the superconducting transition temperature T of the second superconducting layer to increase. c The change causes the second superconducting layer to switch between superconducting and non-superconducting states, modulating the Josephson coupling of the entire device, and ultimately achieving the control of the superconducting critical current I. cThe amplitude is modulated to achieve the storage of "0" and "1". Therefore, the storage unit containing this magnetic spin valve is a non-volatile superconducting storage unit that is written by a magnetic field and read by electricity. Due to the modulating effect of the first and second ferromagnetic layers, the second superconducting layer can switch between superconducting and non-superconducting states. When the first and second ferromagnetic layers are in a parallel state, the superconductivity of the second superconducting layer is completely destroyed; while when the first and second ferromagnetic layers are in an antiparallel state, the superconductivity is preserved. The storage unit containing this magnetic spin valve can therefore achieve complete on / off control of the superconducting current. The magnetic spin valve proposed in this invention innovatively combines a superconducting spin valve and a magnetic Josephson junction, changing the critical superconducting current I... c This enables complete switching of critical superconducting current to increase the storage window, providing a solution for optimizing the overall performance of cryogenic memories. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the magnetic spin valve of the present invention;

[0031] Figure 2 This is a graph showing the comparison of the superconducting transition temperature of the magnetic spin valve of the present invention under different magnetization states.

[0032] Figure 3 This is a schematic diagram of the structure of the magnetic superconducting memory cell of the present invention;

[0033] Figure 4 The magnetic hysteresis loop of the magnetic spin valve structure at low temperature in Embodiment 1 of the present invention;

[0034] Figure 5 This is a schematic diagram of the magnetic superconducting memory cell during testing in Embodiment 2 of the present invention;

[0035] Figure 6 This is an IV diagram showing the magnetization directions of the first ferromagnetic layer and the second ferromagnetic layer in the magnetic superconducting memory cell of Embodiment 2 of the present invention being the same or opposite. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0037] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0038] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0039] In the description of this invention, it should be understood that the orientation or positional relationship indicated by terms such as "above" is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use, or the orientation or positional relationship in which those skilled in the art are usually understood. It is only for the convenience of describing this invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0040] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0042] This application provides a magnetic spin valve, such as... Figure 1 As shown, it includes:

[0043] First superconducting layer 11;

[0044] The first ferromagnetic layer 12 is located on one side of the first superconducting layer 11;

[0045] The second superconducting layer 13 is located on the side of the first ferromagnetic layer 12 away from the first superconducting layer 11;

[0046] The second ferromagnetic layer 14 is located on the side of the second superconducting layer 13 away from the first superconducting layer 11;

[0047] The third superconducting layer 15 is located on the side of the second ferromagnetic layer 14 away from the first superconducting layer 11;

[0048] The first ferromagnetic layer 12 and the second ferromagnetic layer 14 may be made of different materials or the first ferromagnetic layer 12 and the second ferromagnetic layer 14 may be made of the same material but have different thicknesses.

[0049] It should be noted that the magnetic spin valve of this application includes a first superconducting layer 11, a first ferromagnetic layer 12, a second superconducting layer 13, a second ferromagnetic layer 14, and a third superconducting layer 15 stacked sequentially. The magnetic spin valve of this application is a Josephson junction structure of superconducting layer / non-superconducting layer / superconducting layer. The superconducting layers on both sides of the non-superconducting layer are the first superconducting layer 11 and the third superconducting layer 15. The non-superconducting layer is composed of the first ferromagnetic layer 12, the second superconducting layer 13, and the second ferromagnetic layer 14. The non-superconducting layer portion alone is a superconducting spin valve structure of ferromagnetic layer / superconducting layer / ferromagnetic layer. The first ferromagnetic layer 12 and the second ferromagnetic layer 14 of this application are made of different materials or are made of the same material but with different thicknesses. That is, the first ferromagnetic layer 12 and the second ferromagnetic layer 14 use different materials or the same material of different thicknesses to ensure that the first ferromagnetic layer 12 and the second ferromagnetic layer 14 have different coercivities, enabling the transformation between parallel and antiparallel states. The magnetic spin valve of this application, by changing the parallel or antiparallel magnetization of the first ferromagnetic layer 12 and the second ferromagnetic layer 14, generates a magnetic exchange effect that causes the superconducting transition temperature T of the second superconducting layer 13 to increase. c The change causes the second superconducting layer 13 to switch between superconducting and non-superconducting states, modulating the Josephson coupling of the entire device, and ultimately achieving the control of the superconducting critical current I. c The amplitude is adjusted to achieve the storage of "0" and "1". Therefore, the storage unit containing this magnetic spin valve is a non-volatile superconducting storage unit that is written by a magnetic field and read by electricity. Due to the modulation effect of the first ferromagnetic layer 12 and the second ferromagnetic layer 14, the second superconducting layer 13 can switch between superconducting and non-superconducting states. When the first ferromagnetic layer 12 and the second ferromagnetic layer 14 are in a parallel state, the superconductivity of the second superconducting layer 13 is completely destroyed; while when the first ferromagnetic layer 12 and the second ferromagnetic layer 14 are in an antiparallel state, the superconductivity is preserved. Therefore, the storage unit containing this magnetic spin valve can achieve complete switching control of the superconducting current. The magnetic spin valve proposed in this application innovatively combines a superconducting spin valve and a magnetic Josephson junction, changing the critical superconducting current I. c This enables complete switching of critical superconducting current to increase the storage window, providing a solution for optimizing the overall performance of cryogenic memories.

[0050] Specifically, Figure 2 This paper compares the superconducting transition temperature of the magnetic spin valve provided in this application under different magnetization states. By utilizing the parallel or antiparallel magnetization of the upper and lower ferromagnetic layers to generate magnetic exchange effects of varying magnitudes, the superconducting transition temperature T is affected. c Regulation is carried out. Among them, T... c The modulation amplitude is defined as T in antiparallel and parallel states. c The difference: in, Indicates antiparallel T c value, Indicates parallel T c value.

[0051] When ΔT c When sufficiently large, the magnetic exchange interaction in the parallel state can completely suppress superconductivity. At this point, the parallel state is a finite resistance state while the antiparallel state is a superconducting zero resistance state, and the magnetoresistance ratio of the system is MR = (R max –R min ) / R min =(R P -R AP ) / R AP As it approaches infinity, the storage window becomes extremely large; where R... P R is the resistance of the system when the first and second ferromagnetic layers are magnetized in parallel. AP The resistance of the system when the first and second ferromagnetic layers are magnetized in antiparallel order; Figure 2 China T op This is the Toperation temperature (i.e., the test temperature). At this temperature, the MR value obtained by testing the device is infinite.

[0052] In some embodiments, the materials used for the first ferromagnetic layer 12 and the second ferromagnetic layer 14 include any one of magnetic transition metal materials, in-plane or perpendicular magnetic anisotropic ferromagnetic materials, rare earth metal materials, and materials containing rare earth elements.

[0053] In some embodiments, the magnetic transition metal material includes any one of the conventional 3d magnetic transition metals such as iron, cobalt, and nickel.

[0054] In some embodiments, the in-plane or perpendicular magnetic anisotropic ferromagnetic material includes any one of nickel-iron (NiFe) alloy, cobalt-iron-boron (CoFeB) alloy, and cobalt-platinum (Co / Pt) alloy.

[0055] In some embodiments, the rare earth metal material includes any one of europium, gadolinium, holmium, dysprosium, and gadolinium-dysprosium alloy; the rare earth element-containing material includes any one of europium sulfide, gadolinium nitride, holmium nitride, dysprosium nitride, dysprosium sulfide, gadolinium sulfide, and holmium sulfide. The above-mentioned rare earth metal material or rare earth element-containing material used has a large superconducting transition temperature difference ΔTc.

[0056] In some embodiments, the second superconducting layer 13 is made of a different material than the first superconducting layer 11 or the third superconducting layer 15, or the second superconducting layer 13 is made of the same material as the first superconducting layer 11 or the third superconducting layer 15 but has a different thickness.

[0057] Specifically, in the above embodiments, the second superconducting layer 13 is made of a different material than the first superconducting layer 11, or the second superconducting layer 13 is made of the same material as the first superconducting layer 11 but with a different thickness; or the second superconducting layer 13 is made of a different material than the third superconducting layer 15; or the second superconducting layer 13 is made of the same material as the third superconducting layer 15 but with a different thickness. The purpose of this arrangement is to make the superconducting transition temperature of the second superconducting layer 13 more sensitive to changes in the magnetization arrangement of the two ferromagnetic layers (i.e., the first ferromagnetic layer 12 and the second ferromagnetic layer 14). If the material and thickness of the second superconducting layer 13 are completely identical to those of the first superconducting layer 11 and the third superconducting layer 15, the second superconducting layer 13 may not be controlled by the magnetization arrangement of the ferromagnetic layers, and may even prevent the entire magnetic spin valve function from being realized.

[0058] In some embodiments, the first superconducting layer 11 and the third superconducting layer 15 are made of the same material and have the same thickness.

[0059] In some embodiments, the materials used for the second superconducting layer 13, the first superconducting layer 11, and the third superconducting layer 15 are superconducting materials, including any one of superconducting materials of metals or alloys such as niobium (Nb), niobium titanium (NbTi), niobium tin (Nb3Sn), and vanadium germanium (V3Ga).

[0060] Based on the same inventive concept, this application also provides a magnetic superconducting storage cell, including the aforementioned magnetic spin valve.

[0061] In some embodiments, reference Figure 3 As shown, the aforementioned magnetic superconducting memory cell also includes a substrate 10 and a top electrode 16. The first superconducting layer 11 is located on one side of the substrate 10, and the top electrode 16 is located on the side of the third superconducting layer 15 away from the first superconducting layer 11.

[0062] The magnetic superconducting memory cell of this application includes a substrate 10, a first superconducting layer 11, a first ferromagnetic layer 12, a second superconducting layer 13, a second ferromagnetic layer 14, a third superconducting layer 15, and a top electrode 16, which are stacked sequentially.

[0063] In some embodiments, the substrate includes at least one of a single-crystal silicon wafer substrate, a single-crystal sapphire substrate, and a single-crystal magnesium oxide substrate; these substrates are provided to induce a good epitaxial growth relationship.

[0064] In some embodiments, the top electrode 16 is made of a superconducting metal. Using a superconducting metal as the top electrode 16 can avoid energy dissipation at the contact point. Specifically, superconducting metals include superconducting materials of metals or alloys such as niobium (Nb), niobium titanium (NbTi), niobium tin (Nb3Sn), and vanadium germanium (V3Ga).

[0065] The shape of the magnetic superconducting memory cell in this application can be determined according to the actual use. For example, the shape of the magnetic superconducting memory cell can be square, rectangular (the aspect ratio can be any value), circular or elliptical (the aspect ratio can be any value). That is to say, the shape of the memory cell is one of square, rectangular, circular and elliptical.

[0066] Based on the same inventive concept, this application also provides a method for preparing the above-mentioned magnetic superconducting memory cell, comprising the following steps:

[0067] A magnetic superconducting memory cell is obtained by sequentially depositing a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a second ferromagnetic layer, a third superconducting layer, and a top electrode on a substrate.

[0068] Specifically, a magnetic superconducting memory cell is obtained by sequentially depositing a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a third superconducting layer, and a top electrode on a substrate using high-quality magnetron epitaxial growth film structure deposition, atomic layer deposition, or PVD deposition.

[0069] This application also provides a magnetic storage device, the preparation method of which is as follows: using a pre-designed mask, the magnetic superconducting storage cell is patterned by exposure, development and etching to obtain the magnetic storage device.

[0070] The magnetic spin valve and magnetic superconducting storage unit of this application are further described below with specific embodiments. This section further illustrates the content of the present invention with reference to specific embodiments, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0071] Example 1

[0072] This application provides a magnetic spin valve, comprising a first superconducting layer 11, a first ferromagnetic layer 12, a second superconducting layer 13, a second ferromagnetic layer 14, and a third superconducting layer 15 stacked sequentially; wherein the first superconducting layer 11, the third superconducting layer 15, and the second superconducting layer 13 are all made of niobium (Nb), the first superconducting layer 11 and the third superconducting layer 15 have the same thickness, and the thickness of the second superconducting layer 13 is different from that of the first superconducting layer 11; the first ferromagnetic layer 12 is made of holmium (Ho), and the second ferromagnetic layer 14 is made of dysprosium (Dy).

[0073] Example 2

[0074] This application provides a magnetic superconducting memory cell, comprising a substrate 10, a first superconducting layer 11, a first ferromagnetic layer 12, a second superconducting layer 13, a second ferromagnetic layer 14, a third superconducting layer 15, and a top electrode 16, which are stacked sequentially. The substrate 10 is a single-crystal silicon wafer. The first superconducting layer 11, the third superconducting layer 15, and the second superconducting layer 13 are all made of niobium (Nb). The first superconducting layer 11 and the third superconducting layer 15 have the same thickness, while the second superconducting layer 13 has a different thickness than the first superconducting layer 11. The first ferromagnetic layer 12 is made of holmium (Ho), and the second ferromagnetic layer 14 is made of dysprosium (Dy). The top electrode 16 is made of niobium (Nb).

[0075] Figure 4 The magnetic hysteresis loop of the magnetic spin valve structure in Example 1 at low temperature was measured at 10K. Figure 4 The middle arrows indicate the magnetization orientation of the first and second ferromagnetic layers (arrows pointing in the same direction indicate that the first and second ferromagnetic layers are in a parallel state, while arrows pointing in opposite directions indicate that the first and second ferromagnetic layers are in an antiparallel state). The coercivity of the first and second ferromagnetic layers varies with their thickness, and the magnetization orientation can be better adjusted to achieve a completely parallel or antiparallel state by adjusting the thickness of the first and second ferromagnetic layers.

[0076] Figure 5 This is a schematic diagram of the magnetic superconducting memory cell test in Example 2. Bias current flows into the first superconducting layer 11 and out through the top electrode 16. A voltmeter measures the voltage across the two electrodes. When the magnetization directions of the first ferromagnetic layer 12 and the second ferromagnetic layer 14 are opposite, the second superconducting layer 13 is in a superconducting state, corresponding to a zero-resistance state R0 (R0 is minimal), as shown below. Figure 6 Left figure; When the magnetization directions of the first ferromagnetic layer 12 and the second ferromagnetic layer 14 are the same, the second superconducting layer 13 is in a non-superconducting state, corresponding to the high-resistivity state R1, as shown. Figure 6 The diagram on the right illustrates how to store "0" and "1".

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A magnetic spin valve, characterized in that, include: First superconducting layer; The first ferromagnetic layer is located on one side of the first superconducting layer; The second superconducting layer is located on the side of the first ferromagnetic layer away from the first superconducting layer; The second ferromagnetic layer is located on the side of the second superconducting layer away from the first superconducting layer; The third superconducting layer is located on the side of the second ferromagnetic layer away from the first superconducting layer; The first ferromagnetic layer and the second ferromagnetic layer are made of different materials, or the first ferromagnetic layer and the second ferromagnetic layer are made of the same material but have different thicknesses. The second superconducting layer is made of a different material than the first or third superconducting layer, or the second superconducting layer is made of the same material as the first or third superconducting layer but has a different thickness. By altering the parallel and antiparallel magnetization alignment of the first and second ferromagnetic layers, the resulting magnetic exchange effect induces a change in the superconducting transition temperature of the second superconducting layer. T c The change causes the second superconducting layer to switch between superconducting and non-superconducting states, modulating the Josephson coupling of the entire device, and ultimately achieving control over the superconducting critical current. I c Amplitude adjustment enables the storage of "0" and "1".

2. The magnetic spin valve as described in claim 1, characterized in that, The materials used for the first ferromagnetic layer and the second ferromagnetic layer include any one of the following: magnetic transition metal materials, in-plane or perpendicular magnetic anisotropic ferromagnetic materials, rare earth metal materials, and materials containing rare earth elements.

3. The magnetic spin valve as described in claim 2, characterized in that, The magnetic transition metal material includes any one of iron, cobalt, and nickel.

4. The magnetic spin valve as described in claim 2, characterized in that, The in-plane or perpendicular magnetic anisotropic ferromagnetic material includes any one of nickel-iron alloy, cobalt-iron-boron alloy, and cobalt-platinum alloy. The rare earth metal material includes any one of europium, gadolinium, holmium, dysprosium, and gadolinium-dysprosium alloy; The rare earth element-containing material includes any one of europium sulfide, gadolinium nitride, holmium nitride, dysprosium nitride, dysprosium sulfide, gadolinium sulfide, and holmium sulfide.

5. The magnetic spin valve as described in claim 1, characterized in that, The materials used for the second superconducting layer, the first superconducting layer, and the third superconducting layer include any one of niobium, niobium-titanium alloy, niobium-tin alloy, and vanadium-germanium.

6. A magnetic superconducting memory cell, characterized in that, Includes the magnetic spin valve as described in any one of claims 1 to 5.

7. The magnetic superconducting memory cell as described in claim 6, characterized in that, It also includes a substrate and a top electrode, wherein the first superconducting layer is located on one side of the substrate and the top electrode is located on the side of the third superconducting layer away from the first superconducting layer.

8. The magnetic superconducting memory cell as described in claim 7, characterized in that, The substrate includes at least one of a single-crystal silicon wafer substrate, a single-crystal sapphire substrate, and a single-crystal magnesium oxide substrate; The top electrode is made of a superconducting metallic material.

9. A method for fabricating a magnetic superconducting memory cell as described in claim 7 or 8, characterized in that, Includes the following steps: A magnetic superconducting memory cell is obtained by sequentially depositing a first superconducting layer, a first ferromagnetic layer, a second superconducting layer, a second ferromagnetic layer, a third superconducting layer, and a top electrode on a substrate.

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