Method for obtaining a superlattice based on transition metal or chalcogen doping and applications

Abstract

The application discloses a method for obtaining a stacking superlattice based on transition metal element or chalcogen element doping and application, and belongs to the technical field of functional devices. The method takes a transition metal dichalcogenide as a parent body, dopes a transition metal element or a chalcogen element, adjusts the stoichiometric ratio of the doping element, balances the formation energy / thermal stability of 1T structure and 1H structure, and realizes self-assembly synthesis of 1T and 1H stacking superlattices. The application constructs a set of regulation and control engineering in the field of functional device application by changing the doping element and the concentration of the doping element, realizes wide application in the fields of adjustable superconducting dimension devices, adjustable Ising superconducting devices, heavy fermion superconducting devices and the like, and the applications show the potential of 1T and 1H stacking superlattices in realizing new quantum phenomena and functional devices, thereby providing a new direction for future scientific and technological development.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional devices, in particular to a method for obtaining stacking superlattice based on transition metal element or chalcogen element doping and application. BACKGROUND

[0002] The vertical heterostructure and superlattice of transition metal dichalcogenides (TMDs) are constructed by stacking two-dimensional TMD layers along the c-axis, and the unique structure combination enables them to possess new physical functions and properties while retaining the inherent electronic and optical properties of each component. They play a crucial role in the field of nanotechnology and materials science.

[0003] In the field of functional devices, the application prospect of TMDs vertical heterostructure and superlattice is particularly broad, for example, they exhibit unique advantages in field effect transistors, photodetectors, photovoltaic devices, and quantum computing elements. Currently, the construction method of such superlattice mainly adopts traditional preparation methods such as epitaxial growth, chemical vapor deposition (CVD), and mechanical exfoliation stacking. However, these methods have some advantages and disadvantages. The current preparation technology of TMDs vertical heterostructure and superlattice has encountered many difficulties in realizing high quality, large size, and multi-layer structure; by improving and optimizing the existing process, as well as exploring more advanced and controllable new preparation technology and materials, the structure and performance of TMDs can be more accurately controlled. This has immeasurable value for promoting the continuous progress of TMDs in the field of nanotechnology and materials science, and for playing its potential in future high-tech applications.

[0004] In recent years, the emergence of a naturally self-assembled alternating layer material provides a new possibility for future alternatives to traditional TMDs vertical heterostructure and superlattice structure. This material can spontaneously organize into an ordered structure using its inherent tendency, thereby avoiding the limitations of traditional layer-by-layer construction. Early studies have proposed some preparation methods for this type of material, particularly for 1T / 1H superlattice materials of tantalum disulfide. However, these methods largely rely on selenium powder, and the specific role of selenium powder in the growth process is not clear, which greatly reduces the operability of successfully preparing 1T / 1H superlattice and limits the doping control ability of the material. In addition, there are problems such as difficulty in preparing 1T and 1H stacking superlattice, poor single crystal quality, uneven properties, and lack of available functional devices.

[0005] Therefore, it is necessary to develop a new method to realize precise control of material composition, structure, and physical properties, and the present application proposes a method for obtaining stacking superlattice based on transition metal element or chalcogen element doping and application to solve the above problems. SUMMARY

[0006] The application aims to provide a method for obtaining 1T and 1H stacking superlattices based on transition metal element or chalcogen element doping, and application, by changing the doping elements and the concentration of the doping elements, a set of regulation engineering in the field of functional device application is constructed, and wide application in the fields of adjustable superconducting dimension device, adjustable Ising superconducting device, heavy fermion superconducting device, etc. is realized, and the potential of 1T and 1H stacking superlattices in realizing new quantum phenomena and functional devices is shown, and a new direction for future scientific and technological development is provided.

[0007] To achieve the above-mentioned purpose, the application provides a method for obtaining 1T and 1H stacking superlattices based on transition metal element or chalcogen element doping, a transition metal dichalcogenide compound is taken as a matrix, transition metal elements or chalcogen elements are doped, the stoichiometric ratio of the doping elements is adjusted, the formation energy / thermal stability of 1T structure and 1H structure is balanced, and the self-assembly synthesis of 1T and 1H stacking superlattices is realized.

[0008] The transition metal element is one or more of vanadium, niobium, tantalum, titanium, molybdenum and tungsten, and the chalcogen element is one or more of sulfur, selenium and tellurium.

[0009] The application provides a 1T and 1H stacking superlattice prepared by the above-mentioned preparation method.

[0010] Preferably, the 1T and 1H stacking superlattice comprises 1T / 1H stacking superlattice (containing 4H b and 6R two kinds of stacking superlattices), 1T / 1T / 1H stacking superlattice and 1T / 1H / 1H stacking superlattice, etc.

[0011] Preferably, the specific preparation steps of the 1T and 1H stacking superlattice are as follows:

[0012] S1, the doping element raw material and the transition metal dichalcogenide compound matrix raw material are weighed, the doping element is a transition metal element or a chalcogen element, and the total stoichiometric ratio of the transition metal element and the chalcogen element is 1:2;

[0013] S2, after the raw materials weighed in S1 are mixed and uniformly ground, the raw materials are placed in a muffle furnace with a temperature of 700-900 DEG C for 3-6 days to obtain a mixed and uniform polycrystalline powder;

[0014] S3, the obtained polycrystalline powder is placed in a double-temperature-zone tube furnace, and is grown by using a chemical vapor transport method for 7-10 days;

[0015] S4, quenching in an ice-water mixture to obtain 1T and 1H stacking superlattices.

[0016] Preferably, the combined characterization method of the 1T and 1H stacked superlattice is: combined scanning transmission electron microscopy, energy dispersive X-ray spectroscopy, Raman spectroscopy, scanning tunneling microscopy, angle-resolved photoelectron spectroscopy and dilution refrigerator characterization, specifically:

[0017] 1) Adopt scanning transmission electron microscopy, energy dispersive X-ray spectroscopy, scanning tunneling microscopy for combined characterization to determine the basic physical properties of the material, and the basic physical properties include element composition, stoichiometric ratio, crystal structure and surface electronic structure;

[0018] 2) Adopt Raman spectroscopy, angle-resolved photoelectron spectroscopy, dilution refrigerator for combined characterization: reflect the interlayer coupling strength of the 1T and 1H stacked superlattice through the frequency shift of the phonon vibration mode; reflect the electronic dimension of the material through the kz dispersion relationship of the energy band structure; reflect the superconducting dimension and the strength of the Ising through the in-plane and out-of-plane superconducting properties.

[0019] The above-mentioned 1T and 1H stacked superlattice is applied to functional devices, and different functional applications are realized by adjusting the doping elements and the concentration of the doping elements, and the functional devices include adjustable superconducting dimension devices, adjustable Ising superconducting devices and heavy fermion superconducting devices.

[0020] Preferably, the adjustable superconducting dimension device is realized by changing the doping elements and the concentration of the doping elements to adjust the interlayer coupling strength, so as to realize the regulation of the superconducting dimension of the superlattice device; specifically, taking niobium diselenide as the parent body, and doping 0.3% to 3% titanium elements, the 1T / 1H superlattice device can realize two-dimensional conversion of the superconducting dimension, or doping 17% to 30% tellurium elements, the 1T / 1H superlattice device can realize three-dimensional conversion of the superconducting dimension.

[0021] Preferably, the adjustable Ising superconducting device is realized by changing the doping elements and the concentration of the doping elements to adjust the interlayer coupling strength and the insulation of the 1T layer, so as to realize the regulation of the Ising superconducting; specifically, taking niobium diselenide as the parent body, and doping 0.3% to 5% vanadium elements, the Ising superconducting device can realize the ratio of the horizontal critical field to the Pauli paramagnetic limit of 1-20.

[0022] Preferably, the heavy fermion superconducting device is realized by changing the doping elements and the concentration of the doping elements to construct the 1T layer containing local magnetic moment and the 1H layer superlattice containing wandering electrons, so as to obtain the artificial heavy fermion device in the 1T / 1H superlattice; specifically, taking niobium diselenide as the parent body, and doping 0.3% to 7% vanadium elements, the heavy fermion superconducting device can be realized.

[0023] Therefore, the method and application of obtaining stacked superlattice based on transition metal elements or chalcogen elements have the following beneficial effects:

[0024] (1) The present application precisely controls the stoichiometric ratio of each transition metal element and chalcogen element in the preparation method, sintering the polycrystalline powder at high temperature to mix the raw materials uniformly; then growing 1T and 1H stacked superlattices at a specific temperature by chemical vapor transport method, and stabilizing the structure and properties by ice water quenching process, greatly simplifying the preparation process of 1T and 1H stacked superlattices, significantly improving the preparation efficiency and yield. Compared with the traditional multi-step epitaxial growth or mechanical stacking method, the present application provides a new possibility for large-scale preparation of high-quality superlattices, which is expected to accelerate the research and application in related fields.

[0025] (2) The present application realizes the self-assembly synthesis of 1T and 1H stacked superlattices by adjusting the stoichiometric ratio of doping elements (transition metal elements or chalcogen elements), and sintering polycrystalline powder to mix the raw materials uniformly, and ice water quenching to stabilize the superlattice structure and properties during the preparation process. Therefore, under the condition that the growth parameters and environmental variables remain unchanged, the prepared superlattices will exhibit uniform physical properties and excellent crystalline quality, which is crucial for accurate analysis of the samples in various characterization instruments. The high-quality superlattices reduce the crystal defects such as dislocations and impurities in the traditional preparation method, and the uniform physical properties ensure that the performance of the superlattices remains consistent between different regions and different production batches, which is extremely important for scientific research and industrial application.

[0026] (3) The 1T and 1H stacked superlattices prepared by the present application method have great application potential in the field of functional devices, especially in the fields of quantum computing, spintronics and optoelectronics. These high-quality superlattices provide an ideal material platform for realizing new quantum phenomena and developing high-performance devices. For example, in the field of quantum computing, superlattices can be used to build a controllable multi-qubit system to support fast and scalable quantum computing. This can be achieved by building adjustable superconducting dimension devices, adjustable Ising superconducting devices and heavy fermion superconducting devices, etc. These applications demonstrate the potential of 1T and 1H stacked superlattices in realizing new quantum phenomena and functional devices, providing a new direction for future technological development.

[0027] The technical solutions of the present application will be further described in detail below through the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The preparation flow chart of 1T and 1H stacked superlattices in TMDs of the present application;

[0029] Figure 2 Nb 0.9 V 0.1EDS spectrum of Se2 superlattice, wherein (a) and (b) represent EDS spectrum of different regions, respectively;

[0030] Figure 3 Nb 2Se 3 superlattice device of Example 1 of the present application; 0.9 V 0.1 Morphology of Se2 superlattice across 1T layer and 1H layer;

[0031] Figure 4 Nb 2Se 3 superlattice device of Example 1 of the present application; 0.9 V 0.1 Raman spectrum of Se2 superlattice;

[0032] Figure 5 Nb 2Se 3 superlattice device of Example 1 of the present application; 0.9 V 0.1 ARPES band diagram of Se2 superlattice along Γ-M high symmetry direction under different photon energy, wherein (a) is hν = 30 eV; (b) is hν = 35 eV; (c) is hν = 40 eV; (d) is hν = 45 eV;

[0033] Figure 6 Z-contrast atomic image along

[110] direction of Se2 superlattice device of Example 1-3 of the present application, wherein (a) is Nb 2Se 3 superlattice device of Example 1 of the present application; 0.9 V 0.1 Se2, (b) is Nb 2Se 3 superlattice device of Example 2 of the present application; 0.95 Ti 0.05 Se2, (c) is Nb 2Se 3 superlattice device of Example 3 of the present application; 1.11 Te 0.89 ;

[0034] Figure 7 Nb 2Se 3 superlattice device of Example 2 of the present application; 0.95 Ti 0.05 Superconductivity measurement of Se2 superlattice device, wherein (a) is the change of resistance with temperature; (b) is the change of resistance with horizontal magnetic field;

[0035] Figure 8 Nb 2Se 3 superlattice device of Example 2, 3 of the present application; 0.95 Ti 0.05 Se2 and Nb 2Se 3 superlattice device of Example 2, 3 of the present application; 1.11 Te 0.89 The ratio of horizontal critical field to Pauli paramagnetic limit (H c2 / H c2 / H P ) of Se2 superlattice device with doping concentration. DETAILED DESCRIPTION

[0036] The technical solutions of the present application are further illustrated by the accompanying drawings and examples.

[0037] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application.

[0038] A method for obtaining a stacking superlattice based on doping of transition metal elements or chalcogen elements is given in the present application, as shown in Figure 1 By doping regulation, the 1T / 1H superlattice device capable of realizing different functional applications can be realized.

[0039] Embodiment 1

[0040] Preparation of 1T / 1H Nb 0.9 V 0.1 Se2 superlattice: taking niobium diselenide (NbSe2) as a parent body, and doping vanadium (V) element with a doping concentration of 3.33%.

[0041] 1) According to the stoichiometric ratio of Nb:V:Se=0.9:0.1:2, 0.51g of niobium (Nb) powder, 0.31g of vanadium (V) powder and 0.96g of selenium (Se) powder are mixed;

[0042] 2) The mixed raw materials are placed in a muffle furnace, and kept at 850℃ for 4 days to form a uniformly mixed polycrystalline powder;

[0043] 3) The polycrystalline powder is transferred to a double-temperature-zone tube furnace, and iodine (I2) is used as a transport agent, the reaction zone temperature is set to 900℃, the growth zone temperature is set to 800℃, and the growth period is 10 days;

[0044] 4) The grown sample is quickly placed in a pre-prepared ice-water mixture for quenching treatment to stabilize the superlattice structure and improve the crystalline quality, and a 1T / 1H Nb 0.9 V 0.1 Se2 superlattice material is obtained.

[0045] The 1T / 1H Nb 0.9 V 0.1 Se2 superlattice material obtained in Embodiment 1 is jointly tested and characterized:

[0046] ① The elemental composition and stoichiometric ratio of the material obtained in Embodiment 1 are analyzed by energy dispersive X-ray spectroscopy (EDS), as shown in Figure 2 To ensure the uniformity of the distribution of the doping element in the obtained material and the accuracy of the stoichiometric ratio, the EDS spectra of 10 different regions are collected for comparison, and it is confirmed that the stoichiometric ratio of the obtained material is Nb:V:Se=0.9:0.1:2.

[0047] The analysis of energy dispersive X-ray spectroscopy can determine the doping elements and the concentration of the doping elements in the 1T / 1H superlattice material, which will affect the electron or superconducting dimension, and can be used for the performance regulation of future adjustable superconducting dimension devices and adjustable Ising superconducting devices.

[0048] ②The surface charge density wave of the material obtained in Example 1 was observed at liquid nitrogen temperature by low-temperature scanning tunneling microscope (STM), as shown in FIG. 2, the 1T layer exhibits a periodic charge density wave, a Star of David pattern, the Star of David cluster is composed of 13 Nb atoms, the 12 Nb 4d orbits on the periphery form 6 full bands, and the Nb 4d orbit in the center can provide a local magnetic moment. The 1H layer has no obvious charge density wave. Figure 3

[0049] The scanning tunneling microscopy technique can be used for the performance characterization of future heavy fermion superconducting devices. The Star of David pattern observed in the 1T layer indicates that there is a local magnetic moment in the material, the metallic and superconducting properties of the 1H layer can be characterized by scanning tunneling spectroscopy (STS), and it can be proved that there are roving electrons in the material. In theory, coupling the 1T layer containing a local magnetic moment and the 1H layer containing roving electrons will be expected to build a heavy fermion superconducting device, the performance of which mainly depends on the strength of the Kondo interaction, and the Kondo resonance peak can be detected by the STS technique.

[0050] ③The phonon vibration mode of the material obtained in Example 1 was analyzed by a Raman spectrometer, as shown in FIG. 3. Figure 4 The laser wavelength was selected as 532 nm, and the material had phonon vibration modes E -1 and A 2g in the wave number range of 100-400 cm 1g , wherein the E 2g mode is related to the vibration of in-plane phonons, and the A 1g mode is related to the vibration of out-of-plane phonons. Compared with the undoped NbSe2 parent material, the V-doped superlattice shows obvious changes in phonon vibration modes, mainly the blue shift of the E 2g mode and the red shift of the A 1g mode, and the frequency shift reflects that the 1T / 1H superlattice Nb 0.9 V 0.1 Se2 prepared based on V doping has a certain degree of interlayer decoupling, indicating that the electronic dimension of the material is reduced.

[0051] The analysis of the phonon vibration mode in the Raman spectrum can be used to reflect the strength of the interlayer coupling of the 1T and 1H stacking superlattice, and further reflect the trend of the change of the electronic dimension of the material, which can be used as a characterization method of the electronic dimension of future adjustable superconducting dimension devices and adjustable Ising superconducting devices.

[0052] ④The electronic structure of the material obtained in Example 1 was characterized by angle-resolved photoelectron spectroscopy (ARPES),​Figure 5 The band structure along the Γ-M high-symmetry direction at different photon energies is shown in FIG. 2. The band structure is basically consistent at different photon energies, indicating that the material has quasi-two-dimensional properties. Figure 5

[0053] The angle-resolved photoelectron spectrometer can be used for characterization of the electronic dimension of future adjustable superconducting dimension devices and adjustable Ising superconducting devices.

[0054] Example 2

[0055] Preparation of 1T / 1H NbSe 0.95 Ti 0.05 Se2 superlattice: using niobium diselenide (NbSe2) as the parent body, and doping 1.67% titanium (Ti) elements.

[0056] 1) Mix 0.53 g of niobium (Nb) powder, 0.014 g of titanium (Ti) powder, and 0.95 g of selenium (Se) powder according to the stoichiometric ratio of Nb:Ti:Se=0.95:0.05:2;

[0057] 2) Put the mixed raw materials in a muffle furnace and keep at 850°C for 4 days to form a uniformly mixed polycrystalline powder;

[0058] 3) Transfer the polycrystalline powder to a double-temperature zone tube furnace, use iodine (I2) as the transport agent, set the reaction zone temperature to 900°C and the growth zone temperature to 800°C, and the growth period to 10 days;

[0059] 4) Quickly put the grown sample into a pre-prepared ice-water mixture for quenching treatment to stabilize the superlattice structure and improve the crystalline quality, and obtain the 1T / 1H Nb 0.95 Ti 0.05 Se2 superlattice material.

[0060] Example 3

[0061] Preparation of 1T / 1H NbSe 1.11 Te 0.89 superlattice: using niobium diselenide (NbSe2) as the parent body, and doping 29.67% tellurium (Te) elements.

[0062] 1) Mix 0.47 g of niobium (Nb) powder, 0.45 g of selenium (Se) powder, and 0.58 g of tellurium (Te) powder according to the stoichiometric ratio of Nb:Se:Te=1:1.11:0.89;

[0063] 2) Put the mixed raw materials in a muffle furnace and keep at 750°C for 4 days to form a uniformly mixed polycrystalline powder;

[0064] ​3) The polycrystalline powder is transferred to a double-temperature zone tube furnace, iodine (I2) is used as a transport agent, the reaction zone temperature is set to 850°C, the growth zone temperature is set to 800°C, and the growth cycle is 7 days;

[0065] 4) The grown sample is quickly placed in a pre-prepared ice-water mixture for quenching treatment to stabilize the superlattice structure and improve the crystalline quality, obtaining 1T / 1H NbSe 1.11 Te 0.89 superlattice material.

[0066] The crystal lattice structure of the materials obtained in the above Examples 1-3 is characterized using high-angle annular dark field scanning transmission (HAADF-STEM) atomic imaging technology, as shown in FIGS. 1-3. Figure 6 As shown in FIGS. 1-3, the three obtained materials are all structures of alternating stacking of 1T layers and 1H layers, which are 1T / 1H stacking superlattices, the 1T layers are octahedral coordination structures, and the 1H layers are three-prism coordination structures. Among them, the Nb 0.9 V 0.1 Se2 superlattice and the Nb 0.95 Ti 0.05 Se2 superlattice are obtained by C2 rotation symmetry operation, and are stacked in accordance with the ABAB sequence, which is consistent with the 4H b superlattice model in the 1T / 1H stacking superlattice. 1.11 Te 0.89 The adjacent 1T layers (or 1H layers) in the superlattice are obtained by slip operation, and are stacked in accordance with the ABCABC sequence, which is consistent with the 6R superlattice model in the 1T / 1H stacking superlattice.

[0067] The structure characterization of the obtained 1T / 1H superlattice material using HAADF-STEM can be used for the construction and performance explanation of future adjustable superconducting dimension devices, adjustable Ising superconducting devices, and heavy fermion superconducting devices. The 1T layers in the 1T / 1H superlattice can be used as a Mott insulating shielding layer, and the strength of the insulation affects the degree of decoupling between the superlattice layers, and then affects the electron or superconducting dimension, which can be used for the preparation of adjustable superconducting dimension devices and adjustable Ising superconducting devices. In some cases, the 1T layers in the 1T / 1H superlattice can provide local magnetic moments, and the 1H layers provide itinerant electrons, and the coupling of the local magnetic moments and the itinerant electrons will be expected to construct a heavy fermion superconducting device. The following will be discussed in combination with specific examples.

[0068] Device Example 1

[0069] The 1T / 1H stacking superlattice Nb 0.95 Ti 0.05The prepared superconducting device is prepared into a superconducting device, and low-temperature physical property measurement is performed on the superconducting device by using a Triton dilution refrigerator of Oxford Instruments. The system can provide a maximum magnetic field of 14T, and the lowest temperature of the sample can reach 30mK. As shown in Figure 7 (a), the prepared superconducting device enters a superconducting transition interval at 3.3K, and the resistance decreases to zero at 2.9K. The superconducting transition temperature is 3.09K (the temperature corresponding to half of the normal state resistance value). As shown in Figure 7 (b), the horizontal critical magnetic field of the prepared superconducting device is 6.71T (the magnetic field corresponding to half of the normal state resistance value) when the stable temperature is 0.2K.

[0070] Device embodiment 2

[0071] The 1T / 1H superlattice Nb 0.95 Ti 0.05 Se2 and NbSe 1.11 Te 0.89 are prepared into a superconducting device. As shown in Figure 8 , the superconducting dimension of the superlattice device can be controlled by changing the doping element and the concentration of the doping element. The superconducting dimension is described by the ratio of the horizontal critical field to the Pauli paramagnetic limit (H c2 / H P ): H c2 / H P >1, indicating two-dimensional superconductivity, and H c2 / H P <1, indicating three-dimensional superconductivity. When the doping element is Ti, H c2 / H P ≈1.2, obtaining a two-dimensional superconducting device; changing the doping element to Te, H c2 / H P <1, obtaining a three-dimensional superconducting device. When the doping element is fixed as Te, the doping concentration is changed to 29.67% and 21.33% respectively, and the H c2 / H P values are significantly different, indicating that the dimension of the superconducting device can be controlled.

[0072] Therefore, the method and application of obtaining a superlattice based on transition metal elements or chalcogen elements, growing into 1T and 1H superlattices, and constructing a set of control engineering in the field of functional device application by changing the doping element and the concentration of the doping element, realize the wide application in the fields of adjustable superconducting dimension device, adjustable Ising superconducting device, and heavy fermion superconducting device. These applications show the potential of 1T and 1H superlattices in realizing new quantum phenomena and functional devices, and provide a new direction for future technological development.

[0073] It should be pointed out finally that the above examples are only used to illustrate the technical solutions of the present application but not to limit it, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can still be modified or replaced equivalently, and these modifications or equivalent replacements should not make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1.A method for obtaining a stacking superlattice based on transition metal element or chalcogen element doping, characterized in that: a transition metal dichalcogenide is used as a parent material, transition metal elements or chalcogen elements are doped, and by adjusting the stoichiometric ratio of the doping elements, the formation energy or thermal stability of 1T structure and 1H structure is balanced to realize the self-assembly synthesis of 1T and 1H stacking superlattice; the transition metal elements are one or more of vanadium, niobium, tantalum, titanium, molybdenum and tungsten; the chalcogen elements are one or more of sulfur, selenium and tellurium; the specific preparation steps of the 1T and 1H stacking superlattice are: S1, weighing the raw materials of the doping elements and the parent material of the transition metal dichalcogenide, the doping elements being transition metal elements or chalcogen elements, and the total stoichiometric ratio of the transition metal elements and the chalcogen elements being 1:2; S2, mixing and grinding the weighed raw materials in S1 uniformly, and then placing them in a muffle furnace with a temperature of 700-900℃ for 3-6 days to obtain a mixed and uniform polycrystalline powder; S3, placing the obtained polycrystalline powder in a double-temperature-zone tube furnace and growing it by chemical vapor transport method for 7-10 days; S4, quenching in an ice-water mixture to obtain the 1T and 1H stacking superlattice; the combined characterization method of the 1T and 1H stacking superlattice is: combined scanning transmission electron microscopy, energy dispersive X-ray spectroscopy, Raman spectroscopy, scanning tunneling microscopy, angle-resolved photoelectron spectroscopy and dilution refrigerator characterization, specifically: 1) combined scanning transmission electron microscopy, energy dispersive X-ray spectroscopy and scanning tunneling microscopy are used for combined characterization to determine the basic physical properties of the material, including element composition, stoichiometric ratio, crystal structure and surface electronic structure; 2) combined Raman spectroscopy, angle-resolved photoelectron spectroscopy and dilution refrigerator are used for combined characterization: the strength of the interlayer coupling of the 1T and 1H stacking superlattice is reflected by the frequency shift of the phonon vibration mode; the electronic dimension of the material is reflected by the kz dispersion relationship of the energy band structure; the superconducting dimension and the strength of the Ising are reflected by the in-plane and out-of-plane superconducting properties; the 1T and 1H stacking superlattice is applied to functional devices, and different functions are realized by adjusting the doping elements and the concentration of the doping elements, the functional devices including adjustable superconducting dimension devices, adjustable Ising superconducting devices and heavy fermion superconducting devices; the analysis of the energy dispersive X-ray spectrum determines the doping elements and the concentration of the doping elements in the superlattice material, which will affect the electronic or superconducting dimension, and is used for performance control of the adjustable superconducting dimension devices and the adjustable Ising superconducting devices; scanning tunneling microscopy is used for performance characterization of the heavy fermion superconducting devices; the analysis of the phonon vibration mode in the Raman spectrum is used to reflect the strength of the interlayer coupling of the 1T and 1H stacking superlattice, and further reflect the trend of the change of the electronic dimension of the material, which is used as a characterization method of the electronic dimension of the adjustable superconducting dimension devices and the adjustable Ising superconducting devices; the angle-resolved photoelectron spectroscopy is used for characterization of the electronic dimension of the adjustable superconducting dimension devices and the adjustable Ising superconducting devices; the adjustable superconducting dimension devices are obtained by changing the doping elements and the concentration of the doping elements to adjust the interlayer coupling strength, thereby realizing the control of the superconducting dimension of the superlattice device. ​ 1T and 1H stacked superlattices include 1T / 1H stacked superlattices, 1T / 1T / 1H stacked superlattices, and 1T / 1H / 1H stacked superlattices; 1T / 1H stacked superlattices contain both 4H b and 6R stacked superlattices, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The adjustable Ising superconducting device is used for adjusting Ising superconductivity by changing a doping element and a concentration of the doping element, and adjusting interlayer coupling strength and insulation of the 1T layer. The heavy fermion superconducting device is used for obtaining an artificial heavy fermion device in a 1T / 1H superlattice by changing a doping element and a concentration of the doping element, constructing a 1T layer containing a local magnetic moment and a 1H layer superlattice containing a wandering electron.

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