Superconducting diode based on superconducting quantum interference, preparation method thereof and quantum device

Abstract

The invention provides a superconducting diode based on superconducting quantum interference, a preparation method thereof and a quantum device. The superconducting diode provided by the invention can realize a one-way conduction function at an extremely low temperature, and has extremely low power consumption, so that basic parts of a low-temperature quantum circuit are greatly expanded. And the required external magnetic field is very small and can be provided by an external magnet and a current circuit prepared on the same chip as the device, so that the application is convenient. In addition, under low-temperature microwave irradiation, the device shows the capacity of small change along with microwave power, and it is indicated that the device also has the stable working capacity in the high-power microwave environment.

Description

Technical Field

[0001] The present invention belongs to the field of diodes, and in particular relates to a superconducting diode based on superconducting quantum interference, a preparation method thereof, and a quantum device. Background Art

[0002] In the semiconductor field, the discovery and development of diodes has driven the development of semiconductor computer technology. With the advancement of science and technology, particularly cryogenics, research on low-temperature quantum circuits, focusing on superconducting quantum computing, has also increased. Quantum circuits or devices operating at low temperatures require lower power than those operating at room temperature to prevent self-heating of the device from damaging the low-temperature environment and thus affecting the performance of the quantum circuit. Therefore, the design and research of low-power quantum devices that can operate in low-temperature environments is of paramount importance.

[0003] The power of common diodes operating at room temperature is relatively high. Even lower-power diodes are generally above the mW level, and the power of diodes deviceized in general chips is also above the uW level. Although the cooling power of currently commonly used low-temperature refrigeration systems can reach nearly the W level at around 1K, the operating power of the device, which is far less than the system cooling power, can increase the local temperature. For example, at the operating temperature of a superconducting quantum computer of around 10mK, the system cooling power to maintain this low temperature is about 10uW, but the nanowatt-level device power may increase the temperature of the device itself to 100mK, thereby affecting the extremely low temperature environment and the performance of the quantum computer. Therefore, there is an urgent need to develop a new low-temperature quantum device such as a diode with extremely low power consumption so that it can be used in low or even ultra-low temperatures, thereby expanding the research of ultra-low temperature quantum circuits and related low-power logic circuits. Summary of the Invention

[0004] Therefore, the purpose of the present invention is to overcome the shortcomings of the prior art and provide a superconducting diode based on superconducting quantum interference, a method for preparing the same, and a quantum device. The present invention's superconducting diode based on superconducting quantum interference solves the problem of traditional semiconductor diodes being unable to operate at low or even ultra-low temperatures, providing a new low-power electronic component implementation solution for quantum circuits at low temperatures, and in particular, a new solution for the exploration of new quantum logic circuits at ultra-low temperatures.

[0005] Before describing the present invention, the terms used in this article are defined as follows:

[0006] The term "superconducting diode" refers to an electronic device based on the superconducting phenomenon, which has non-reciprocal or directional current transmission characteristics, that is, it allows a larger superconducting current to pass in one direction, but suppresses or blocks the superconducting current in the other direction. In other words, it has superconducting state and normal state resistance under different directions of bias current.

[0007] The term "material having edge states" refers to a material in which electronic states different from those in the interior of the material appear at the edge of the material.

[0008] The term "carrier concentration" refers to the number of electrons or holes involved in conduction per unit volume, usually expressed in cubic centimeters (cm -3 ).

[0009] The term "Ta2Pd3Te5" refers to: tantalum, palladium, tellurium.

[0010] The term "true four-terminal method" refers to a method that can accurately measure the resistance of a device using four leads, with four electrodes actually present in the part that contacts the sample.

[0011] The term "pseudo-four-terminal method" refers to a method that can accurately measure the resistance of a device using four leads. However, the difference between the resistance measured by the true four-terminal method and the pseudo-four-terminal method is that the part in contact with the sample is only two electrodes, so the measurement result may include contact resistance.

[0012] The term "MIBK" means: methyl isobutyl ketone.

[0013] The term "IPA" means: Isopropyl alcohol.

[0014] The term "PMMA" means: polymethyl methacrylate.

[0015] The term "PDMS" refers to: polydimethylsiloxane.

[0016] The term "second-order topological insulator" refers to a material in which the bulk state is a three-dimensional insulator and the edge states appear on one-dimensional edges (edge states).

[0017] The term "quantum spin Hall insulator" refers to a material that generally exists in a two-dimensional system, where the bulk state is insulating but edge states with spin-momentum locking exist at the boundary.

[0018] The term "quantum anomalous Hall insulator" refers to a two-dimensional magnetic topological insulator with bulk insulation, edge states, and magnetism. Its core characteristics are quantized Hall conductance and vanishing longitudinal resistance under zero magnetic field.

[0019] To achieve the above object, a first aspect of the present invention provides a superconducting diode based on superconducting quantum interference, wherein the superconducting diode comprises, from bottom to top:

[0020] insulating substrate;

[0021] a thin layer of material on the insulating substrate;

[0022] a superconducting electrode located on the thin layer of material, wherein the thin layer of material and the superconducting electrode form a Josephson junction; and

[0023] A protective layer covering the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode; and wherein:

[0024] The superconducting electrodes include one or more electrodes selected from the group consisting of: a measuring electrode, a source electrode, and a drain electrode;

[0025] The thin layer material and the superconducting electrodes across its two sides together form an asymmetric Josephson junction, in which the interference supercurrents generated on the two sides of the thin layer material that are not connected to the superconducting electrodes are asymmetric;

[0026] Preferably, the thickness of the thin layer material is 0.4 to 100 nm, more preferably 1.0 to 90 nm, and even more preferably 5.0 to 70 nm.

[0027] The superconducting diode according to the first aspect of the present invention, wherein:

[0028] The thin layer material with edge states is selected from one or more of the following: second-order topological insulators, quantum spin Hall insulators, quantum anomalous Hall insulators, preferably one or more of the following: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, ZrTe5, HfTe5, WTe2, MoTe2, TaIrTe4, Bi4Br4, Bi4I4, Sb2Te3, Bi2Se3, Bi2Te3, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7, HgTe / CdTe quantum wells, InAs / GaSb quantum wells, more preferably one or more of the following: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, ZrTe5, HfTe5, WTe2, MoTe2, TaIrTe4, Bi4Br4, Bi4I4, Sb2Te3, Bi2Se3, Bi2Te3, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7, further preferably selected from the following one or more: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, TaIrTe4, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7;

[0029] Alternatively, the thin layer material having edge states is made of a material having a three-dimensional carrier concentration greater than 1x10 18 cm -3 , preferably greater than 1x1019 cm -3 , more preferably greater than 1x10 20 cm -3 Thin layer of material instead;

[0030] Preferably, the three-dimensional carrier concentration is greater than 1x10 18 cm -3 The composition of the thin layer material is selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, WSe2, more preferably selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, further preferably selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2.

[0031] The superconducting diode according to the first aspect of the present invention, wherein:

[0032] The material of the insulating substrate is selected from one or more of the following: silicon wafer containing a silicon dioxide layer, sapphire, mica sheet, strontium titanium oxide, preferably selected from one or more of the following: silicon wafer containing a silicon dioxide layer, sapphire, mica sheet, most preferably a silicon wafer containing a silicon dioxide layer;

[0033] The material of the superconducting electrode is selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode, lead electrode, molybdenum-rhenium electrode, preferably selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode, lead electrode, more preferably selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode; and / or

[0034] The material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, electron beam photoresist, boron nitride, preferably selected from one or more of the following: PMMA, electron beam photoresist, boron nitride, more preferably PMMA or boron nitride.

[0035] The superconducting diode according to the first aspect of the present invention, wherein:

[0036] The superconducting electrodes include: a measuring electrode, a source electrode and a drain electrode; and / or

[0037] The layout of the superconducting electrodes is a pseudo four-terminal layout or a true four-terminal layout, and the true four-terminal layout is most preferred;

[0038] Preferably, the number of the measuring electrodes is 2 or more, more preferably 2 to 6, and even more preferably 2 to 4; and / or

[0039] Preferably, the distance between the source electrode and the drain electrode is 300 nm or less, more preferably 50 to 300 nm, and even more preferably 100 to 200 nm.

[0040] According to the superconducting diode of the first aspect of the present invention, in the superconducting diode, each of the superconducting electrodes is connected to a pad and an external lead.

[0041] A second aspect of the present invention provides a method for preparing the superconducting diode according to the first aspect, the method comprising the following steps:

[0042] 1) preparing the thin layer material and transferring it onto the insulating substrate;

[0043] 2) The insulating substrate containing the thin layer material prepared in step 1) is used to prepare the superconducting diode through a micro-nano processing method.

[0044] According to the method of the second aspect of the present invention, in step 1), the method for preparing the thin layer material is selected from one or more of the following: tape dissociation, PDMS dissociation, chemical vapor transport, molecular beam epitaxy, and pulsed laser deposition, preferably selected from one or more of the following: tape dissociation, PDMS dissociation, and chemical vapor transport, more preferably tape dissociation and / or PDMS dissociation.

[0045] According to the method of the second aspect of the present invention, the step 2) includes the following steps:

[0046] a) spin-coating a photoresist on the insulating substrate containing the thin layer material prepared in step 1), baking the photoresist, exposing, developing, and fixing the photoresist according to the electrode pattern, then etching the developed portion of the thin layer material to deposit a superconducting electrode, and then removing the photoresist;

[0047] b) preparing a protective layer on the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode.

[0048] According to the method of the second aspect of the present invention, the method further comprises the following steps:

[0049] 3) When the material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, and electron beam photoresist, spin-coating photoresist on the protective layer prepared in step b), exposing, developing, and fixing according to the pad pattern to obtain a pad, installing the external lead on each of the superconducting electrodes, and connecting the pad and the external lead to an external source surface; or

[0050] When the material of the protective layer is boron nitride, the boron nitride is directly covered on the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode without photolithography pads.

[0051] A third aspect of the present invention provides a superconducting quantum device capable of operating in a low temperature and / or small magnetic field environment, wherein the superconducting quantum device comprises the superconducting diode described in the first aspect;

[0052] Preferably, the low temperature environment is a temperature below the superconducting transition temperature of the material of the superconducting quantum device, preferably 0.01K to 300K, more preferably 0.3K to 100K, and further preferably 1.6K to 77K;

[0053] Preferably, the small magnetic field environment has a magnetic induction intensity below the superconducting critical magnetic field of the material of the superconducting quantum device, preferably 0.001mT to 1T, more preferably 0.001mT to 0.1T, and further preferably below 10mT; and / or

[0054] Preferably, the superconducting quantum device is selected from one or more of the following: a superconducting diode, a superconducting quantum interference device, and a superconducting logic gate.

[0055] According to a preferred embodiment of the present invention, the Josephson junction based on superconducting quantum interference of the present invention, i.e., a superconducting diode, comprises an insulating substrate, a material having edge states or a common material, a superconducting electrode and a protective layer; wherein,

[0056] The material having edge states has properties of bulk insulation and edge state conductivity;

[0057] Preferably, the thin layer material with edge states is a second-order topological insulator, a quantum spin Hall insulator, or a quantum anomalous Hall insulator. The material with edge states is selected from one or more of the following: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, ZrTe5, HfTe5, WTe2, MoTe2, TaIrTe4, Bi4Br4, Bi4I4, Sb2Te3, Bi2Se3, Bi2Te3, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7, HgTe / CdTe quantum well, InAs / GaSb quantum well. The thickness of the thin layer material is 0.4nm to 100nm;

[0058] Preferably, the common material has a relatively high carrier concentration (three-dimensional carrier concentration greater than 1x10 18 cm -3) thin layer material, in addition to the above-mentioned materials with edge states, can also be selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, WSe2, etc.

[0059] The insulating substrate is selected from one or more of the following: a silicon wafer containing a silicon dioxide layer, sapphire, a mica sheet, and strontium titanium oxide.

[0060] The superconducting electrode is selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode, lead electrode, and molybdenum-rhenium electrode.

[0061] The material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, electron beam photoresist, and boron nitride.

[0062] The method for preparing a superconducting diode based on superconducting quantum interference of the present invention comprises the following steps:

[0063] (1) preparing the material into a thin layer material;

[0064] (2) The Josephson junction based on superconducting quantum interference effect is prepared by micro-nano processing method.

[0065] In the step (1), the preparation method of the thin layer material is selected from one or more of the following: tape dissociation, PDMS dissociation, chemical vapor transport, molecular beam epitaxy, and pulsed laser deposition, preferably tape dissociation and PDMS dissociation.

[0066] In the step (2), the micro-nano processing method for preparing the Josephson junction based on superconducting quantum interference includes the following:

[0067] (a) Based on step (1), the thin layer of material is transferred to an insulating substrate, a photoresist is spin-coated, baked, and the photoresist is exposed, developed, and fixed according to the electrode pattern. Note that the distance between the two superconducting electrodes is preferably within 300nm to better ensure adjacent superconductors;

[0068] (b) slightly etching and removing the oxide layer on the electrode pattern developed in step (a), plating a superconducting electrode, and then removing the photoresist; and

[0069] (c) spin-coating photoresist on the entire substrate, exposing, developing, and fixing the pads to expose the pads, thereby obtaining the Josephson junction based on superconducting quantum interference, and thus realizing a superconducting diode;

[0070] Preferably, in step (c), each of the superconducting electrodes is provided with a pad for bonding a wire to connect to an external device.

[0071] The superconducting diode of the present invention can be used in a low-temperature environment, which refers to a temperature below the superconducting transition temperature of the superconducting electrode.

[0072] According to another preferred embodiment of the present invention, a superconducting diode is prepared using a thin layer material having edge states, taking Ta2Pd3Te5 as an example. The method for preparing a superconducting diode based on superconducting quantum interference of the present invention comprises the following steps:

[0073] (1) Dissociate bulk Ta2Pd3Te5 single crystal material into thin layer material;

[0074] (2) Micro-nano sized Ta2Pd3Te5 materials and superconducting electrodes are prepared to obtain Josephson junctions to realize superconducting diodes.

[0075] Realizing the function of a superconducting diode includes the following steps:

[0076] (1) connecting the lead or pad of the Josephson junction to an external source meter;

[0077] (2) A superconducting diode is realized by combining a source-meter input current signal with an external magnetic field.

[0078] The present invention can realize obtaining a high-efficiency and stable superconducting diode under a relatively small external magnetic field and below the superconducting transition temperature.

[0079] According to another preferred embodiment of the present invention, two Josephson junctions of different sizes are prepared using common thin layer materials to form a superconducting quantum interference device; wherein,

[0080] Preferably, the Josephson junction based on superconducting quantum interference includes: a substrate, conventional materials, a superconducting electrode and a protective layer.

[0081] The material of the insulating substrate is selected from one or more of the following: silicon wafer (the silicon wafer is a silicon wafer containing a silicon dioxide layer), sapphire, mica sheet, strontium titanium oxide; and / or

[0082] The thickness of the ordinary thin layer material is 0.4nm to 100nm;

[0083] Preferably, the insulating substrate is a silicon wafer containing silicon dioxide; and / or

[0084] The conventional material has a relatively high carrier concentration (three-dimensional carrier concentration greater than 1x10 18 cm -3 ) thin layer material can be selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, WSe2.

[0085] The superconducting electrodes include a measuring electrode, a drain electrode and a source electrode, wherein the superconducting electrodes are preferably selected from one or more of the following: a titanium-aluminum electrode, a niobium electrode, a niobium-titanium electrode, a niobium-titanium-nitrogen electrode, a lead electrode, a molybdenum-rhenium electrode; and / or

[0086] The material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, electron beam photoresist, and boron nitride;

[0087] Preferably, the superconducting diode having the edge state thin layer material further comprises a pad.

[0088] The method for preparing a superconducting diode of the present invention comprises the following steps:

[0089] (1) Preparation of thin layer materials;

[0090] (2) Prepare Josephson junctions that can produce superconducting quantum interference through micro-nano processing methods.

[0091] In the step (1), the method for preparing the thin layer material is selected from one or more of the following: tape dissociation, PDMS dissociation, chemical vapor transport, molecular beam epitaxy, and pulsed laser deposition, preferably tape dissociation and PDMS dissociation; and / or

[0092] In the step (2), the micro-nano processing method for preparing the Josephson junction capable of generating superconducting quantum interference includes the following:

[0093] (c) Based on step (1), the thin layer of material is transferred to an insulating substrate, a photoresist is spin-coated, heated, and the photoresist is exposed, developed, and fixed according to the electrode pattern. Note that the distance between the two superconducting electrodes should preferably be within 300 nm to ensure adjacent superconductors.

[0094] (d) evaporating superconducting electrodes, including a measuring electrode, a drain electrode, and a source electrode, on the electrode pattern developed in step (c), and then removing the photoresist; and

[0095] (e) spin-coating a photoresist on the entire substrate, exposing, developing, and fixing the pad to obtain the Josephson junction based on superconducting quantum interference;

[0096] Preferably, in step (d), the measuring electrode, the drain electrode and the source electrode are all provided with pads for bonding wires to connect to external devices; and / or the number of the measuring electrodes is greater than or equal to two.

[0097] The superconducting diode of the present invention can be used in low-temperature and small magnetic field equipment, wherein:

[0098] The cryogenic temperature generally refers to a temperature below the superconducting transition temperature of the material, which is generally below 77K.

[0099] The small magnetic field generally refers to a material below its superconducting critical magnetic field, which is generally below 10 millitesla.

[0100] A Josephson junction refers to the junction area composed of a superconducting electrode + a thin layer of material sandwiched in the middle + a superconducting electrode.

[0101] The resistance of the Josephson junction has superconducting state and normal state resistance under bias currents in different directions at low temperature, and is also called a superconducting diode.

[0102] The Josephson junction comprises a thin layer material having edge states, and the thin layer material and superconducting electrodes spanning two sides thereof form an asymmetric Josephson junction, wherein the interference supercurrents on two sides of the thin layer material that are not connected to the superconducting electrodes are asymmetric;

[0103] Alternatively, the Josephson junction comprises an ordinary thin layer material and forms two Josephson junctions with inconsistent cross-sectional areas together with a superconducting electrode across the thin layer, so that the two Josephson junctions generate inconsistent interference supercurrents.

[0104] When the thin layer material is a thin layer material with edge states, the superconducting electrodes across the two ends of the Josephson junction form an asymmetric Josephson junction, and the edge states on both sides of the asymmetric Josephson junction that are not connected to the superconducting electrodes interfere with the supercurrent asymmetry; and / or

[0105] When the thin layer material is a conventional thin layer material selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, WSe2, the thin layer material forms two asymmetric Josephson junctions through the superconducting electrodes and forms two asymmetric interference supercurrents.

[0106] The working mechanism of the superconducting diode of the present invention is as follows: below the superconducting transition temperature, when a very small magnetic field (about mT level, the earth's magnetic field is about 0.05 mT) is applied, the corresponding current-voltage curve applied in one direction is inconsistent with the current-voltage curve in the other direction. It manifests itself as a DC current of the same magnitude, when the voltage is 0 (i.e. in a superconducting state) when applied in one direction, and a finite value (i.e. in a normal state) when applied in the opposite direction. This function is similar to the unidirectional conduction property of a semiconductor diode. A superconducting device with this function can be called a superconducting diode. It should be noted that the external magnetic field required here is very small. In addition to being provided by an external magnet, it can also be provided by a current circuit prepared on the same chip as the device, thereby facilitating application.

[0107] The core components of the present invention's low-power superconducting diode based on superconducting quantum interference are a Josephson junction composed of a material with edge state properties and a superconducting electrode, or a superconducting quantum interference device (SQID) formed by fabricating two asymmetric Josephson junctions from conventional materials and superconducting electrodes. The asymmetry of the interferometric supercurrent in the Josephson junction creates a unidirectional conduction characteristic similar to that of a semiconductor diode: when current is applied in one direction, the device is in a superconducting state, while when current is applied in the opposite direction, the device is in a normal state. A major advantage of this superconducting diode is its low power consumption, easily reaching the nanowatt level or even below the picowatt level. When using a Josephson junction composed of a material with edge state properties and a superconducting electrode, the edge supercurrent channel is much smaller than the bulk supercurrent channel for devices of the same thickness, while conventional semiconductor diodes typically consume power in the microwatt or even milliwatt range. When using two asymmetric Josephson junctions fabricated from conventional materials and superconducting electrodes to form a SQID, the narrower the Josephson junction design, the narrower the interferometric supercurrent channel, thus achieving low power consumption. These low-power devices provide new fundamental circuit components for quantum circuits in cryogenic and even ultra-cold environments (below 100mK). They can even be compared to the role of semiconductor diodes in chips and modern electronic circuits. This is because some commercial systems that maintain cryogenic environments (e.g., below 1K) require cooling power levels below the watt level. Localized milliwatt or even microwatt power levels can heat the local temperature, thus affecting the functionality of cryogenic devices. Therefore, new functional devices with extremely low power consumption at low temperatures are urgently needed to construct cryogenic quantum circuits.

[0108] The superconducting diode based on superconducting quantum interference of the present invention solves the problem that traditional semiconductor diodes cannot work at low temperatures or even very low temperatures. When using topological materials (materials with both bulk and edge states), superconducting electrodes spanning two edges are prepared on the material to form an asymmetric Josephson junction, inducing supercurrents caused by superconducting quantum interference on the edge states on both sides; when using ordinary materials, two Josephson junctions with smaller cross-sectional areas and asymmetric structures are prepared on the material through superconducting electrodes to achieve two asymmetric interference supercurrents. All of the above can produce superconducting diodes with extremely low power consumption. When using topological materials, the edge supercurrent channels corresponding to the Josephson junction of the same thickness are far fewer than the bulk supercurrent channels, thereby achieving extremely low power consumption superconducting diodes. When using ordinary materials, the process is stable, the range of materials available for preparing the Josephson junction is extremely wide, and it is easy to implement. In addition, the required external magnetic field can be very easily reduced (to below the earth's magnetic field level of 0.05mT) so that the magnetic field can be driven by local current. The superconducting diode based on superconducting quantum interference of the present invention provides a new low-power electronic component implementation solution for quantum circuits at low temperatures, and in particular provides a new solution for the exploration of new quantum logic circuits at extremely low temperatures.

[0109] The superconducting diode of the present invention can achieve diode functionality with extremely low power consumption at low temperatures. Its core component is an asymmetric Josephson junction or superconducting quantum interference device. At low temperatures and a small magnetic field, the device exhibits properties of a superconducting state and a normal resistive state under a certain range of positive and negative bias currents, respectively, i.e., the superconducting diode effect. This superconducting diode can exhibit high efficiency and extremely low power, less than one millionth of the power of conventional semiconductor diodes. It also has relatively stable performance in microwave environments. This provides new technical support for new quantum circuits and even quantum logic circuits in low-temperature and even ultra-low-temperature environments.

[0110] Compared with the prior art, the superconducting diode based on superconducting quantum interference, its preparation method and quantum device of the present invention can have but are not limited to the following beneficial effects:

[0111] 1. The superconducting diode constructed by the thin layer material of the present invention can achieve a unidirectional conduction function at extremely low temperatures and has extremely low power consumption. The unidirectional conduction function here is that, under a very small external magnetic field, when a DC current within a specific range is applied in one direction, it is in a superconducting state, and when a current within a specific range is applied in the other direction, it is in a normal state. This function can constitute a logic circuit similar to a traditional semiconductor diode, thereby greatly expanding the basic components of low-temperature quantum circuits. It should be noted that the external magnetic field required here is very small. In addition to being provided by an external magnet, it can also be provided by a current circuit prepared on the same chip as the device, thereby facilitating application.

[0112] 2. The present invention exhibits minimal variation with microwave power under low-temperature microwave irradiation, demonstrating its ability to operate stably even in higher-power microwave environments. This is crucial. For example, quantum computing, a promising approach to increasing computing power, typically requires extremely low temperatures and relatively high microwave power, making the stability of cryogenic electronic components under microwave conditions crucial. BRIEF DESCRIPTION OF THE DRAWINGS

[0113] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which:

[0114] Figure 1 A schematic cross-sectional view of a superconducting diode based on edge state material according to embodiment 1 of the present invention is shown.

[0115] Figure 2 A schematic top view of a superconducting diode based on edge state material according to embodiment 1 of the present invention is shown.

[0116] Figure 3 An enlarged view of a superconducting diode based on a material having edge states according to Example 1 of the present invention is shown, and the edge states of the material are marked with dotted arrows.

[0117] Figure 4 A schematic diagram of the working principle of a superconducting diode based on edge state materials prepared in Example 1 of the present invention is shown.

[0118] Figure 5 FIG1 shows the relationship between the resistance and bias current of the superconducting diode prepared in Example 1 of the present invention; wherein, Figure 5 (a) shows the obvious inconsistent behavior of the resistance of the superconducting diode of the present invention with the positive and negative bias current directions at low temperature and weak magnetic field (about 2.7 mT); Figure 5 (b) shows that under low temperature and weak magnetic field, when a positive and negative bias current is applied, the resistor will exhibit stable superconducting zero resistance and high resistance states, that is, the superconducting diode effect; this shows that the present invention has stable working performance.

[0119] Figure 6 Other basic properties of the superconducting diode prepared in Example 1 of the present invention are shown; Figure 6 (a) shows the relationship between the resistance and temperature of an embodiment of the present invention, showing that its superconducting transition temperature is about 0.51K, where half of the normal resistance is taken as the superconducting transition temperature; Figure 6 (b) shows the superconducting critical current (I c+ ), the negative superconducting critical current (I c- ) and the difference between the positive and negative critical currents (ΔI c =I c+ -|I c- |) changes with the magnetic field, demonstrating the interference effect of edge-state superfluidity; Figure 6 (c) shows I c+ ,I c- , ΔI c =I c+ -|I c- |As the temperature changes, it can be seen that the superconducting diode effect weakens when the temperature approaches the superconducting transition temperature; Figure 6 (d) shows I c+ ,I c- and ΔI c With the change of the external microwave power, it can be seen that with the increase of microwave power, the superconducting diode effect ΔI c The decay of the microwave power is relatively slow, indicating that it has relatively stable performance even at higher microwave power.

[0120] Figure 7 A schematic top view of a superconducting diode based on conventional materials according to Example 4 of the present invention is shown.

[0121] Figure 8 An enlarged view of a superconducting diode based on conventional materials and a schematic diagram of the working principle of the superconducting diode according to Example 4 of the present invention are shown.

[0122] Figure 9 The basic properties of the superconducting diode of Example 4 of the present invention are shown; Figure 9 (a) shows the relationship between the resistance and temperature of an embodiment of the present invention, indicating that its superconducting transition temperature is about 1.23K; Figure 9 (b) shows an embodiment of the present invention I c+ ,I c- and ΔI c The relationship between the change of the magnetic field and the asymmetric superfluidity effect of superconducting quantum interference is demonstrated; Figure 9 (c) shows the obvious inconsistent behavior of the resistance of the superconducting diode according to the embodiment of the present invention at low temperature and weak magnetic field (about -0.06 mT) with the positive and negative bias current directions; Figure 9 (d) shows that in Example 4 of the present invention, I c+ ,I c- and ΔI c With the change of the external microwave power, it can be seen that with the increase of microwave power, the superconducting diode effect ΔI c The attenuation of Figure 6 (d) is similar and relatively slow, indicating that it has relatively stable performance even at higher microwave power.

[0123] Description of reference numerals:

[0124] 110. Silicon oxide layer on substrate silicon wafer; 120. Substrate silicon wafer; 130. Superconducting drain electrode; 140. Superconducting source electrode; 150. Thin layer material; 160. Protective layer; 170. Superconducting measuring electrode; 180. Pad; 190. Edge state of thin layer material; 200. Josephson junction. DETAILED DESCRIPTION

[0125] The present invention will be further described below through specific embodiments in conjunction with the accompanying drawings. However, it should be understood that these embodiments are only used for more detailed and specific description and should not be understood as limiting the present invention in any form.

[0126] This section provides a general description of the materials and experimental methods used in the experiments of the present invention. Although many of the materials and procedures used to achieve the purposes of the present invention are well known in the art, the present invention is described herein in as much detail as possible. It will be understood by those skilled in the art that, unless otherwise specified, the materials and procedures used in the present invention are well known in the art.

[0127] The reagents and instruments used in the following examples are as follows:

[0128] Material:

[0129] PDMS was purchased from Shanghai Angwei Technology Co., Ltd.

[0130] Reagents:

[0131] Acetone and isopropanol were purchased from Beijing Tongguang Fine Chemical Company;

[0132] The developer, a mixture of methyl isobutyl ketone (MIBK) and isopropyl alcohol (IPA) in a ratio of 1:3, was purchased from Kayaku Advanced Materials Co., Ltd.

[0133] PMMA was purchased from MicroChem.

[0134] instrument:

[0135] The coating equipment was purchased from Hefei Kaibai Technology Co., Ltd., model JEB-2 electron beam evaporation coating system.

[0136] The cryostat instrument was purchased from Oxford Instruments Co., Ltd., a model 6-2-2T liquid helium-free vector magnet cryostat system.

[0137] Digital lock-in amplifier, purchased from NF Co., Ltd. of Japan, model LI5640 or LI5650.

[0138] Example 1

[0139] This embodiment is an exemplary description of the superconducting diode based on superconducting quantum interference and the preparation method of the present invention.

[0140] like Figure 1 and Figure 2 As shown, the superconducting diode based on superconducting quantum interference of the present invention includes: a silicon oxide layer 110 on an insulating silicon substrate, an insulating silicon substrate 120, a superconducting drain electrode 130, a superconducting source electrode 140, a thin layer of material 150, a protective layer 160, a superconducting measuring electrode 170, and a bonding pad 180. The silicon oxide layer and the silicon wafer constitute the insulating substrate, the thin layer of material is located on the silicon oxide layer, the superconducting electrode is located on the thin layer of material and forms a Josephson junction with the thin layer of material, and the protective layer covers the insulating substrate and the Josephson junction formed by the thin layer of material and the superconducting electrode.

[0141] The superconducting diode based on superconducting quantum interference of the present invention is fabricated on a topological material (a material having both bulk and edge states) with superconducting electrodes across two edges to form an asymmetric Josephson junction, inducing supercurrent due to superconducting quantum interference in the edge states on both sides. This asymmetry mainly comes from the asymmetry of the edge states or the asymmetry caused by the interface differences of the edge state Josephson junction. The edge supercurrent channels of the corresponding Josephson junction of the same thickness are far fewer than the bulk supercurrent channels, thus realizing a superconducting diode with extremely low power consumption.

[0142] The insulating substrate is generally a silicon substrate 120 containing 300-nanometer-thick silicon dioxide 110, but this is not specifically limited here. The thin layer material 150 in this embodiment can be obtained using methods such as tape desorption, chemical vapor transport, and molecular beam epitaxy, which are not specified in this invention. The measuring electrode, source electrode, and drain electrode can be plated with superconducting electrodes such as titanium aluminum electrodes, niobium, lead, molybdenum rhenium, etc., which are not specified in this invention. The protective layer can be made of a photoresist such as polymethyl methacrylate (PMMA), which is also not specified in this invention. The electrode layout adopts a pseudo-four-terminal structure, but can also adopt a true four-terminal or multi-terminal structure, which is not specified here. In this embodiment, the substrate is a silicon substrate 120 containing 300-nanometer-thick silicon dioxide 110, and the thin layer material 150 is Ta2Pd3Te5. The preparation method is tape desorption. The superconducting drain electrode, superconducting source electrode, and superconducting measuring electrode are made of titanium aluminum electrodes, and the protective layer is made of PMMA.

[0143] The preparation of a Josephson junction based on a thin layer material with edge states is relatively complex and requires the use of micro-nano processing technology. The specific steps for preparing a superconducting diode based on a Josephson junction of a thin layer material with edge states in this embodiment are as follows:

[0144] The first step is to transfer the Ta2Pd3Te5 thin layer material 150 dissociated by the tape to the silicon dioxide 110 of the insulating substrate.

[0145] Step 2: Spin-coat PMMA photoresist onto the entire substrate containing the thin layer material and heat-cure the photoresist. The photoresist is exposed, developed, and fixed according to the designed electrode pattern. Specifically, the PMMA photoresist is exposed using electron beam lithography, and the exposed PMMA photoresist is developed using a developer consisting of a mixture of methyl isobutyl ketone (MIBK) and isopropyl alcohol (IPA). Isopropyl alcohol is used for fixing. The spacing between the superconducting source and drain electrodes is 300±50nm.

[0146] Step 3: Use JEB-2 to argon ion etch for about ten seconds to clean the oxide layer on the developed electrode pattern, then evaporate the source and drain electrodes and the measuring superconducting electrode material. In this embodiment, titanium aluminum electrodes are used, and then remove the photoresist with acetone.

[0147] Step 4: Since the material is easily oxidized when it dissociates into thin layers, PMMA photoresist is spin-coated on the entire substrate for protection.

[0148] Step 5: Expose the pad 180 area according to the design, develop and fix it, and finally prepare the Josephson junction with superconducting diode effect.

[0149] Figure 3 FIG1 shows a partial enlarged view of a Josephson junction based on a thin layer material with edge states prepared in this embodiment. Figure 3 and Figure 2 As shown: In order to facilitate the connection of the device with external equipment, each electrode of the device (including the superconducting source electrode 140, the superconducting drain electrode 130 and the superconducting measurement electrode 170) is designed with a pad 180 for bonding wires to connect with external equipment (i.e., Figure 3 The material of the pad 180 can usually be the same as the material of the electrode to which it is connected, and the external lead connected to the pad can be made of aluminum wire or gold wire. It should be noted that: Figure 3 The edge states of thin films in 190 are intrinsic properties of topological materials. For perfect films, there are only two edge states (such as Figure 3 ); Imperfect films may have multiple edge states, for example, there may be multiple imperfect stacks in the middle of the thin layer. This is common when physically separating thin layers, and almost all of them can produce a superconducting diode effect based on this Josephson junction, without specific restrictions here; Figure 3 The number of measuring electrodes 170 shown in FIG is only schematic. Figure 3 As can be seen in the figure, there are two auxiliary measurement electrodes 170, which can be increased (as in the multi-terminal electrode layout described in the previous paragraph), but must not be less than two. To reduce the uncontrollable effects of contact resistance and line resistance on measurement, this embodiment uses two as an example. This layout enables the thermometer device to be adapted to different applications, enhancing its flexibility and adaptability.

[0150] Example 2

[0151] This embodiment is used to illustrate the working principle of the present invention based on a superconducting diode of a thin layer material with edge states.

[0152] This embodiment takes the superconducting diode prepared in Example 1 as an example. Figure 4A schematic diagram of the operating principle of a superconducting diode based on a thin-layer material with edge states according to Example 1 of the present invention is shown. The source terminal of superconducting source electrode 140 is connected to an AC source meter and a DC source meter. The drain terminal of superconducting drain electrode 130 is grounded and measures current. Two superconducting measuring electrodes 170 measure AC voltage. This is a typical pseudo-four-terminal resistance measurement method. However, the two terminals can also be connected to a DC source meter and a DC voltmeter, respectively, without affecting the function of the device, so no further restrictions are imposed.

[0153] After placing the superconducting diode in the temperature environment to be measured, connect the external measurement circuit as described in the previous paragraph. After applying AC current and DC bias current and a small magnetic field, measure the AC voltage at the two superconducting measurement electrodes 170 to obtain the resistance of the superconducting diode, that is, Figure 5 and Figure 6 Since the superconducting critical current of the Josephson junction is inconsistent when the bias current is applied in the positive and negative directions, see Figure 5 (a), therefore, it can be seen that when a bias current within a certain range in the positive direction is applied, the resistance of the Josephson junction is zero, and when a bias current within the range in the negative direction is applied, the resistance of the Josephson junction is normal, see Figure 5 (b) This property is similar to the diode effect of a traditional semiconductor PN junction, that is, it has a unidirectional conduction property, so a superconducting device with this property is called a superconducting diode.

[0154] Example 3

[0155] This embodiment is used to illustrate the performance characteristics of the superconducting diode of the present invention.

[0156] This embodiment takes the superconducting diode prepared in Example 1 as an example. The relationship between the bias current and resistance of the Josephson junction is measured using the pseudo four-terminal method. Figure 5 FIG1 shows the relationship between the bias current and resistance of the superconducting diode according to an embodiment of the present invention; wherein, Figure 5 (a) shows the obvious inconsistent behavior of the resistance of the superconducting diode of the present invention with the positive and negative bias current directions at low temperature and weak magnetic field; Figure 5 (b) shows that at low temperature and weak magnetic field, when a positive and negative bias current is applied, the resistor exhibits stable superconducting zero resistance and high resistance states, i.e., superconducting diode behavior; Figure 5 (b) This shows that the present invention has stable operating performance, and it can be calculated that the operating power of the device when exhibiting superconducting diode performance is only 29 picowatts, which is less than one millionth of the power of a conventional semiconductor diode.

[0157] Figure 6 Other basic properties of the superconducting diode according to the embodiment of the present invention are shown; Figure 6(a) shows the relationship between the resistance and temperature of an embodiment of the present invention, showing that its superconducting transition temperature is about 0.51K, where half of the normal resistance is taken as the superconducting transition temperature; Figure 6 (b) shows the relationship between Ic+, Ic-, and ΔIc as a function of magnetic field, demonstrating the interference effect of edge-state superfluidity. It can be seen that the superconducting diode effect can occur under many different magnetic fields, especially very small magnetic fields (below 1 mT, the Earth's magnetic field is about 0.05 mT); Figure 6 (c) shows the relationship between Ic+, Ic-, and ΔIc as a function of temperature. It can be seen that the superconducting diode effect is still quite obvious at low temperatures, but it weakens significantly when the temperature approaches the superconducting transition temperature. Figure 6 (d) shows the relationship between Ic+, Ic- and ΔIc as a function of applied microwave power. It can be seen that in the embodiment of the present invention, the superconducting diode effect ΔIc decays relatively slowly with increasing microwave power, indicating that it has good performance even at higher microwave powers.

[0158] Example 4

[0159] This embodiment is another exemplary description of the superconducting diode based on superconducting quantum interference and the preparation method of the present invention.

[0160] Unless otherwise specified, the method for preparing the superconducting diode of this embodiment is the same as that of Example 1 and will not be described in detail here. The structure of the superconducting diode of this embodiment differs from that of Example 1 in the following ways: Figure 7 and Figure 1 This embodiment is a superconducting diode based on superconducting quantum interference of conventional materials. The thin layer material is K2Cr3As3 as an example, and its three-dimensional carrier concentration is about 2.7×10 21 cm -3 The wiring and principle diagram of this embodiment are basically the same as those of embodiment 1, see embodiment 2. The principle of generating a superconducting diode in embodiment 1 is to use a superconducting quantum interference device composed of two asymmetric Josephson structures, while this embodiment uses a superconducting quantum interference device composed of two conventional asymmetric Josephson structures.

[0161] The pseudo four-terminal method is also used to measure the relationship between the bias current and resistance of the device. Figure 9 (a) shows the relationship between the resistance and temperature of the embodiment of the present invention, indicating that its superconducting transition temperature is about 1.23K. Figure 9 (b) shows I c+ , I c- and ΔI cThe relationship between the change in magnetic field and the superfluid interference effect produced by the asymmetric Josephson junction is demonstrated. The superconducting diode effect can be seen in a very small magnetic field (-0.06mT, the Earth's magnetic field is about 0.05mT), which is smaller than the magnetic field required in Example 1 and is very easy to control (by adjusting the area enclosed by the two Josephson junctions). Subsequent improvements can use local current to provide an external magnetic field. Figure 9 (c) shows the obvious inconsistent behavior of the resistance of the superconducting diode of the present invention with the positive and negative bias current directions at low temperature and a weak field of -0.06mT; Figure 9 (d) shows that under microwave irradiation, the superconducting diode effect decays relatively slowly with the increase of microwave power, which is similar to the result of Example 1 (refer to Figure 6 (d)).

[0162] Compared with Example 1, the superconducting diode prepared in this example is stable and easy to implement; the range of materials available for preparing the Josephson junction is extremely wide; the required external magnetic field can be adjusted to be very small, reaching the geomagnetic field level of 0.05 mT; the external magnetic field can be driven by local current, freeing itself from the constraints of components such as external large magnets.

[0163] With the development of technology, more and more devices operate in low-temperature or even ultra-low-temperature environments, such as quantum computing and superconducting electronics. This limits the operation of conventional high-power semiconductor devices at low temperatures. Therefore, the present invention will play its unique advantages in low-temperature quantum circuits and even low-temperature logic circuits.

[0164] Although the effects of some embodiments are shown above, those skilled in the art should understand that, according to the concept of the present invention, other embodiments described above, whose effects are not specifically shown, or other technical solutions of the present invention not shown in the embodiments, can also achieve the following technical effects described in the Summary of the Invention, which are equivalent to those of the embodiments:

[0165] 1. The superconducting diode constructed by the thin layer material of the present invention can achieve a unidirectional conduction function at extremely low temperatures and has extremely low power consumption. The unidirectional conduction function here is that, under a very small external magnetic field, when a DC current within a specific range is applied in one direction, it is in a superconducting state, and when a current within a specific range is applied in the other direction, it is in a normal state. This function can constitute a logic circuit similar to a traditional semiconductor diode, thereby greatly expanding the basic components of low-temperature quantum circuits. It should be noted that the external magnetic field required here is very small. In addition to being provided by an external magnet, it can also be provided by a current circuit prepared on the same chip as the device, thereby facilitating application.

[0166] 2. The present invention exhibits minimal variation with microwave power under low-temperature microwave irradiation, demonstrating its ability to operate stably even in higher-power microwave environments. This is crucial. For example, quantum computing, a promising approach to increasing computing power, typically requires extremely low temperatures and relatively high microwave power, making the stability of cryogenic electronic components under microwave conditions crucial.

[0167] Although the present invention has been described to a certain extent, it is obvious that appropriate changes in various aspects can be made without departing from the spirit and scope of the present invention. It is understood that the present invention is not limited to the embodiments described, but belongs to the scope of the claims, which includes equivalent replacements of each factor described.

Claims

1. A superconducting diode based on superconducting quantum interference, characterized in that: The superconducting diode comprises, from bottom to top,: insulating substrate; a thin layer of material having edge states on the insulating substrate; a superconducting electrode located on the thin layer of material, wherein the thin layer of material and the superconducting electrode form a Josephson junction; and A protective layer covering the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode; and wherein: The superconducting electrodes include one or more electrodes selected from the group consisting of: a measuring electrode, a source electrode, and a drain electrode; The thin layer material and the superconducting electrodes across its two sides together form an asymmetric Josephson junction, in which the interference supercurrents generated on the two sides of the thin layer material that are not connected to the superconducting electrodes are asymmetric; Preferably, the thickness of the thin layer material is 0.4 to 100 nm, more preferably 1.0 to 90 nm, and even more preferably 5.0 to 70 nm.

2. The superconducting diode according to claim 1, wherein: The thin layer material with edge states is selected from one or more of the following: second-order topological insulators, quantum spin Hall insulators, quantum anomalous Hall insulators, preferably one or more of the following: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, ZrTe5, HfTe5, WTe2, MoTe2, TaIrTe4, Bi4Br4, Bi4I4, Sb2Te3, Bi2Se3, Bi2Te3, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7, HgTe / CdTe quantum wells, InAs / GaSb quantum wells, more preferably one or more of the following: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, ZrTe5, HfTe5, WTe2, MoTe2, TaIrTe4, Bi4Br4, Bi4I4, Sb2Te3, Bi2Se3, Bi2Te3, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7, further preferably selected from the following one or more: Ta2Pd3Te5, Ta2Ni3Te5, Ta2NiSe5, TaIrTe4, BiSbTeSe2, Sn-Bi 1.1 Sb 0.9 Te2S, MnBi2Te4, MnBi4Te7; Alternatively, the thin layer material having edge states is made of a material having a three-dimensional carrier concentration greater than 1x10 18 cm -3 , preferably greater than 1x10 19 cm -3 , more preferably greater than 1x10 20 cm -3 Thin layer of material instead; Preferably, the three-dimensional carrier concentration is greater than 1x10 18 cm -3 The composition of the thin layer material is selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, WSe2, more preferably selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2, MoSe2, further preferably selected from one or more of the following: graphite, K2Cr3As3, MoS2, WS2.

3. The superconducting diode according to claim 1 or 2, characterized in that: The material of the insulating substrate is selected from one or more of the following: silicon wafer containing a silicon dioxide layer, sapphire, mica sheet, strontium titanium oxide, preferably selected from one or more of the following: silicon wafer containing a silicon dioxide layer, sapphire, mica sheet, most preferably a silicon wafer containing a silicon dioxide layer; The material of the superconducting electrode is selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode, lead electrode, molybdenum-rhenium electrode, preferably selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode, lead electrode, more preferably selected from one or more of the following: titanium-aluminum electrode, niobium electrode, niobium-titanium electrode, niobium-titanium-nitrogen electrode; and / or The material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, electron beam photoresist, boron nitride, preferably selected from one or more of the following: PMMA, electron beam photoresist, boron nitride, more preferably PMMA or boron nitride.

4. The superconducting diode according to any one of claims 1 to 3, characterized in that: The superconducting electrodes include: a measuring electrode, a source electrode and a drain electrode; and / or The layout of the superconducting electrodes is a pseudo four-terminal layout or a true four-terminal layout, and the true four-terminal layout is most preferred; Preferably, the number of the measuring electrodes is 2 or more, more preferably 2 to 6, and even more preferably 2 to 4; and / or Preferably, the distance between the source electrode and the drain electrode is 300 nm or less, more preferably 50 to 300 nm, and even more preferably 100 to 200 nm.

5. The superconducting diode according to any one of claims 1 to 4, characterized in that In the superconducting diode, each of the superconducting electrodes is connected to a pad and an external lead.

6. A method for preparing a superconducting diode according to any one of claims 1 to 5, characterized in that: The method comprises the following steps: 1) preparing the thin layer material and transferring it onto the insulating substrate; 2) The superconducting diode is prepared by a micro-nano processing method on the insulating substrate containing the thin layer material prepared in step 1).

7. The method according to claim 6, characterized in that In step 1), the method for preparing the thin layer material is selected from one or more of the following: tape dissociation, PDMS dissociation, chemical vapor transport, molecular beam epitaxy, and pulsed laser deposition, preferably selected from one or more of the following: tape dissociation, PDMS dissociation, and chemical vapor transport, more preferably tape dissociation and / or PDMS dissociation.

8. The method according to claim 6 or 7, characterized in that The step 2) includes the following steps: a) spin-coating a photoresist on the insulating substrate containing the thin layer material prepared in step 1), baking the photoresist, exposing, developing, and fixing the photoresist according to the electrode pattern, then etching the developed portion of the thin layer material to deposit a superconducting electrode, and then removing the photoresist; b) preparing a protective layer on the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode.

9. The method according to claim 8, characterized in that The method further comprises the following steps: 3) When the material of the protective layer is selected from one or more of the following: PMMA, ultraviolet photoresist, deep ultraviolet photoresist, extreme ultraviolet photoresist, and electron beam photoresist, spin-coating photoresist on the protective layer prepared in step b), exposing, developing, and fixing according to the pad pattern to obtain a pad, installing the external lead on each of the superconducting electrodes, and connecting the pad and the external lead to an external source surface; or When the material of the protective layer is boron nitride, the boron nitride is directly covered on the insulating substrate and the Josephson junction formed by the thin layer material and the superconducting electrode without photolithography pads.

10. A superconducting quantum device capable of operating in a low temperature and / or small magnetic field environment, characterized in that: The superconducting quantum device comprises a superconducting diode according to any one of claims 1 to 5; Preferably, the low temperature environment is a temperature below the superconducting transition temperature of the material of the superconducting quantum device, preferably 0.01K to 300K, more preferably 0.3K to 100K, and further preferably 1.6K to 77K; Preferably, the small magnetic field environment has a magnetic induction intensity below the superconducting critical magnetic field of the material of the superconducting quantum device, preferably 0.001mT to 1T, more preferably 0.001mT to 0.1T, and further preferably below 10mT; and / or Preferably, the superconducting quantum device is selected from one or more of the following: a superconducting diode, a superconducting quantum interference device, and a superconducting logic gate.

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