A lanthanum-aluminum single crystal, its preparation method and application
By weighing lanthanum and aluminum under a protective atmosphere and performing crystal growth and post-treatment steps in a vacuum environment, high-quality lanthanum aluminum single crystals are prepared, which solves the problem of difficult to produce high-quality topological material single crystals in the prior art, and the combination of giant magnetoresistive effect and high crystallization quality is achieved.
Patent Information
- Application Number
- CN202510315113.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2045-03-18
AI Technical Summary
The prior art is difficult to produce high-quality topological material single crystals, especially while maintaining the giant magnetoresistive effect, there are challenges in ensuring high crystallization quality and large-size lanthanum aluminum single crystals.
By weighing lanthanum and aluminum under a protective atmosphere, controlling its molar ratio within the range of 3: (11-11.8), and performing crystal growth in a vacuum environment, controlling the temperature, time and cooling rate, and combining post-treatment steps such as centrifugation, quenching and flux removal, high-quality lanthanum aluminum single crystals are prepared.
It has achieved high crystallization quality and large size of lanthanum aluminum single crystal, with huge magnetoresistive effect, residual resistivity ratio ≥100 and magnetoresistive ≥3000%, meeting the needs of high-quality and large-size topological materials.
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Figure CN119843367B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of topological materials, and more specifically, to a lanthanum-aluminum single crystal, a preparation method thereof, and an application thereof. Background Art
[0002] Topological materials refer to materials whose electronic states have topological properties. The electronic structures of these materials remain unchanged under specific transformations, and this invariance stems from a special combination of the geometric structure of the materials and electronic interactions. Topological materials have a variety of macroscopic quantum effects. For example, they have a significant giant magnetoresistance effect. When the magnetic field changes, the resistance of topological materials will change greatly, and this characteristic brings new breakthrough opportunities for aspects such as ultra-high density storage and sensor technology; the anomalous Hall and anomalous Nernst effects break the conventional laws of the traditional Hall and Nernst effects, providing unique ideas for the design of new electronic devices; there is also the negative magnetoresistance effect caused by chiral anomaly. This peculiar phenomenon of resistance reduction in a magnetic field has inestimable potential application value in frontier scientific and technological fields such as quantum computing and quantum communication.
[0003] To deeply study and reveal the topological properties and potential application values of topological materials, the first problem to be solved is how to prepare high-quality single crystals of topological materials. High-quality single crystals of topological materials are not only the basis and prerequisite for studying topological properties but also the most critical and important link in the entire research process. Summary of the Invention
[0004] Aiming at the deficiencies in the prior art, the present invention provides a lanthanum-aluminum single crystal, a preparation method thereof, and an application thereof. The lanthanum-aluminum single crystal has high crystal quality, large size, and exhibits a giant magnetoresistance effect.
[0005] The specific technical solution of the present invention is as follows:
[0006] In a first aspect, the present invention provides a lanthanum-aluminum single crystal, in which the molar ratio of lanthanum to aluminum is 3:(11 - 11.8), the residual resistivity ratio of the lanthanum-aluminum single crystal ≥ 100, and the magnetoresistance of the lanthanum-aluminum single crystal at 2K ≥ 3000%.
[0007] The molar ratio of lanthanum to aluminum in the lanthanum-aluminum single crystal provided by the present invention is 3:(11 - 11.8), which is very close to the ideal value of 3:11 for the La3Al 11 single crystal. The lanthanum-aluminum single crystal not only has a high residual resistivity ratio and a huge magnetoresistance but also has very high crystal quality and large size. The length of the lanthanum-aluminum single crystal can reach 5 mm, which can meet the requirements for high-crystal-quality and large-size topological materials.
[0008] In a possible implementation manner, the length of the lanthanum-aluminum single crystal ≥ 0.1 mm.
[0009] Further, the residual resistivity ratio of the lanthanum-aluminum single crystal ≥ 235.
[0010] Further, the magnetoresistance of the lanthanum-aluminum single crystal at 2K ≥ 8000%.
[0011] In a possible implementation, the magnetic susceptibility of the lanthanum-aluminum single crystal at 2K exhibits a quantum oscillation effect.
[0012] In a second aspect, the present invention provides a method for preparing the above-mentioned lanthanum-aluminum single crystal, comprising the following steps:
[0013] S1. Weigh the raw materials: Weigh lanthanum and aluminum in a protective atmosphere, and after mixing, obtain a mixed raw material, wherein the molar ratio of lanthanum to aluminum ≤ 1:10;
[0014] S2. Crystal growth: The mixed raw material in step S1 is subjected to crystal growth in a vacuum environment. The heat preservation temperature for the crystal growth is 900 - 1200 °C, the heat preservation time is more than 1200 min, and after the heat preservation ends, a cooling treatment is carried out at a cooling rate ≤ 3.5 °C / h to obtain a lanthanum-aluminum solution;
[0015] S3. Post-treatment: The lanthanum-aluminum solution in step S2 is subjected to post-treatment to obtain a lanthanum-aluminum single crystal.
[0016] The method for preparing the lanthanum-aluminum single crystal provided by the present invention uses excessive Al as a flux. Since Al is one of the components of the lanthanum-aluminum single crystal, it avoids introducing impurities into the single crystal due to the addition of other fluxes, which is beneficial to obtaining high-quality lanthanum-aluminum single crystals; and by controlling the temperature, time, and cooling rate of crystal growth, it avoids generating more defects during crystal growth, which is beneficial to obtaining lanthanum-aluminum single crystals with fewer defects and high quality; through post-treatment, the lanthanum-aluminum single crystal is separated from the aluminum solution, and the Al flux attached to the surface of the lanthanum-aluminum single crystal is removed to obtain high-quality lanthanum-aluminum single crystals.
[0017] In a possible implementation, the process of weighing the raw materials in step S1 is carried out in a glove box. In the glove box, on the one hand, it is convenient to form a space with a protective atmosphere, and on the other hand, it is also convenient to carry out weighing operations in the protective atmosphere.
[0018] In a possible implementation, the protective atmosphere in step S1 uses at least one of nitrogen and argon.
[0019] In a possible implementation, the molar ratio of lanthanum to aluminum in step S1 is 1:(11 - 15). Controlling the molar ratio of lanthanum to aluminum within the range of 1:(11 - 15) can reduce the growth temperature of the lanthanum-aluminum single crystal while ensuring the acquisition of high-quality lanthanum-aluminum single crystals, which is beneficial to growing high-quality lanthanum-aluminum single crystals at a relatively low temperature.
[0020] In a possible implementation, the specific process of step S1 is as follows: In a glove box with a protective atmosphere, weigh the lanthanum and the aluminum according to the molar ratio and place them in a container. After the lanthanum and the aluminum are evenly mixed, plug the outlet of the container with quartz wool and take it out of the glove box.
[0021] In a possible implementation, the time for the mixed raw materials in step S2 to rise from room temperature to the holding temperature is 800 - 1200 min. By controlling the heating time, the mixed raw materials are slowly heated to the temperature required for crystal growth, avoiding uneven heating of the mixed raw materials due to too fast heating.
[0022] In a possible implementation, the cooling treatment in step S2 adopts one-step cooling or stepwise cooling.
[0023] Further, the process of one-step cooling is to cool down to 700 - 800 °C at a cooling rate of ≤3.5 °C / h. Adopting the one-step cooling method, the process is simpler, and by controlling the cooling rate and the cooling temperature, it is more conducive to the crystal growth of lanthanum-aluminum single crystal.
[0024] Further, the process of stepwise cooling is to cool down to 900 - 950 °C at a cooling rate of ≤3 °C / h, then heat up to 1100 - 1150 °C at a heating rate of 3 - 5 °C / min, and then cool down to 700 - 800 °C at a cooling rate of ≤3 °C / h. By adopting the above stepwise cooling method, it is more conducive to the growth of lanthanum-aluminum single crystal and is beneficial to further improving the magnetoresistance and the ratio of residual resistivity of lanthanum-aluminum single crystal.
[0025] In a possible implementation, the process of forming the vacuum environment in step S2 is as follows: Place the mixed raw materials in step S1 in a sealed container with a protective atmosphere, extract the protective gas in the sealed container, and then vacuum-seal the mixed raw materials in the sealed container by using a high-temperature flame in cooperation with a vacuum pump.
[0026] In a possible implementation, the post-treatment in step S3 includes centrifugal treatment, quenching, and removing the flux.
[0027] Further, the temperature of the centrifugal treatment is 700 - 800 °C.
[0028] Further, the rotation speed of the centrifugal treatment is ≥2500 r / min.
[0029] Further, sodium hydroxide solution is used to remove the flux.
[0030] In a third aspect, the present invention also provides the application of the above lanthanum-aluminum single crystal in the fields of storage, sensors, quantum computing, or quantum communication.
[0031] On the basis of conforming to the common knowledge in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain various preferred examples of the present invention.
[0032] The reagents and raw materials used in the present invention are all commercially available.
[0033] The positive and progressive effects of the present invention are as follows:
[0034] The lanthanum-aluminum single crystal provided by the present invention not only has a high residual resistivity ratio and a huge magnetoresistance, but also has very high crystal quality and large size. The length of the lanthanum-aluminum single crystal can reach 5 mm, which can meet the requirements for high-quality and large-size topological materials, and also enriches the research system of topological materials. The preparation method of the lanthanum-aluminum single crystal provided by the present invention is not only simple and convenient to operate, but also very easy to form high-quality lanthanum-aluminum single crystals. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] Figure 1 It is the powder X-ray diffraction (XRD) pattern of the lanthanum-aluminum single crystal prepared in Example 1.
[0036] Figure 2 It is the micrograph of the lanthanum-aluminum single crystal prepared in Example 1.
[0037] Figure 3 It is the energy dispersive spectroscopy (EDS) of the elements of the lanthanum-aluminum single crystal prepared in Example 1 and the micrograph of the scanning area.
[0038] Figure 4 It is the graph of the resistivity change with temperature of the lanthanum-aluminum single crystals prepared in Example 1 and Example 2.
[0039] Figure 5 It is the graph of the magnetoresistance change with magnetic field of the lanthanum-aluminum single crystals prepared in Example 1 and Example 2 at 2 K.
[0040] Figure 6 It is the graph of the magnetic susceptibility change with magnetic field of the lanthanum-aluminum single crystals prepared in Example 1 and Example 2 at 2 K. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0041] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation methods and typical parameters of the present invention, and are not used to limit the parameter range described in the present invention. Reasonable changes derived therefrom are still within the protection scope of the claims of the present invention.
[0042] It should be noted that the endpoints and any values within the ranges disclosed in this document are not limited to the exact ranges or values. These ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed in this document.
[0043] Unless otherwise defined, all terms, symbols, and other scientific terms used in this document are intended to have the same meaning as commonly understood by those skilled in the art to which this invention pertains. In some cases, for the purpose of clarification or convenient reference, terms with conventional understood meanings are defined in this document, and such definitions in this document should not be construed as indicating a significant difference from the conventional understanding in the art. The technical methods described or cited in this document are generally well understood by those skilled in the art and are adopted by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents, and instruments is carried out according to the protocols and parameters provided by the manufacturers.
[0044] Example 1
[0045] This example provides a lanthanum-aluminum single crystal, which is prepared by the following method:
[0046] S1. Weigh the raw materials: In a glove box filled with nitrogen, weigh lanthanum and aluminum in a molar ratio of 1:13 and place them in a crucible. After the lanthanum and aluminum are mixed evenly, place the crucible in a quartz tube. After stuffing quartz wool at the outlet of the quartz tube, take the quartz tube out of the glove box;
[0047] S2. Crystal growth: Install the quartz tube taken out in step S1 on a vacuum packaging device, extract the nitrogen inside the quartz tube, and use a hydrogen-oxygen machine to vacuum package the quartz tube; Place the vacuum-packaged quartz tube in a muffle furnace. Through 1200 minutes of heating, raise the temperature in the muffle furnace from room temperature to 1200 °C, then keep it at 1200 °C for 1480 minutes, and then cool it at a rate of 2 °C / h to 950 °C, then heat it up to 1150 °C at a rate of 5 °C / min, and then cool it at a rate of 1 °C / h to 800 °C, and keep it at 800 °C. A lanthanum-aluminum solution is obtained inside the quartz tube;
[0048] S3. Post-treatment: After taking out the quartz tube cooled to 800 °C in step S2 from the muffle furnace, invert it in a centrifuge and perform centrifugation for 10 s at a centrifuge speed of 2500 r / min, and then quickly put the quartz tube into cold water for quenching; Open the quartz tube and take out the lanthanum-aluminum single crystal with a metallic luster, and soak the lanthanum-aluminum single crystal in a diluted sodium hydroxide solution to remove the impurities on its surface, obtaining a high-quality lanthanum-aluminum single crystal, denoted as sample 1.
[0049] Example 2
[0050] This example provides a lanthanum-aluminum single crystal, which is prepared by the following method:
[0051] S1. Weigh the raw materials: In a glove box filled with nitrogen, weigh lanthanum and aluminum according to a molar ratio of 1:13 and place them in a crucible. After the lanthanum and aluminum are mixed evenly, place the crucible in a quartz tube. After stuffing quartz wool at the outlet of the quartz tube, take the quartz tube out of the glove box;
[0052] S2. Crystal growth: Install the quartz tube taken out in step S1 on a vacuum packaging device, extract the nitrogen inside the quartz tube, and use a hydrogen-oxygen machine to vacuum-seal the quartz tube; Place the vacuum-sealed quartz tube in a muffle furnace. Through 1000 minutes of heating, raise the temperature in the muffle furnace from room temperature to 1100 °C, then keep it at 1100 °C for 1440 minutes, and then cool it down to 700 °C at a cooling rate of 3 °C / h. A lanthanum-aluminum solution is obtained inside the quartz tube;
[0053] S3. Post-treatment: After taking out the quartz tube cooled to 700 °C in step S2 from the muffle furnace, invert it in a centrifuge and perform centrifugation for 2 minutes, and then take it out of the centrifuge after the quartz tube has cooled to room temperature; Open the quartz tube and take out the lanthanum-aluminum single crystal with a metallic luster. Soak the lanthanum-aluminum single crystal in a diluted sodium hydroxide solution to remove the impurities on its surface, and obtain a high-quality lanthanum-aluminum single crystal, denoted as sample 2.
[0054] Example 3
[0055] This example provides a lanthanum-aluminum single crystal, which is prepared by the following method:
[0056] S1. Weigh the raw materials: In a glove box filled with nitrogen, weigh lanthanum and aluminum according to a molar ratio of 1:15 and place them in a crucible. After the lanthanum and aluminum are mixed evenly, place the crucible in a quartz tube. After stuffing quartz wool at the outlet of the quartz tube, take the quartz tube out of the glove box;
[0057] S2. Crystal growth: Install the quartz tube taken out in step S1 on a vacuum packaging device, extract the nitrogen inside the quartz tube, and use a hydrogen-oxygen machine to vacuum-seal the quartz tube; Place the vacuum-sealed quartz tube in a muffle furnace. Through 1200 minutes of heating, raise the temperature in the muffle furnace from room temperature to 1200 °C, then keep it at 1200 °C for 1480 minutes, and then cool it down to 750 °C at a cooling rate of 2 °C / h. A lanthanum-aluminum solution is obtained inside the quartz tube;
[0058] S3. Post-treatment: After taking out the quartz tube cooled to 750 °C in step S2 from the muffle furnace, place it upside down in a centrifuge and centrifuge for 3 minutes. Then, take out the quartz tube from the centrifuge after it has cooled to room temperature. Open the quartz tube to take out the lanthanum-aluminum single crystal with metallic luster, and soak the lanthanum-aluminum single crystal in a diluted sodium hydroxide solution to remove the impurities on its surface, obtaining a high-quality lanthanum-aluminum single crystal, denoted as Sample 3.
[0059] Example 4
[0060] This example provides a lanthanum-aluminum single crystal, which is prepared by the following method:
[0061] S1. Weigh the raw materials: In a glove box filled with nitrogen, weigh lanthanum and aluminum in a molar ratio of 1:10 and place them in a crucible. After mixing lanthanum and aluminum evenly, place the crucible in a quartz tube. After stuffing quartz wool at the outlet of the quartz tube, take out the quartz tube from the glove box.
[0062] S2. Crystal growth: Install the quartz tube taken out in step S1 on a vacuum packaging device, extract the nitrogen inside the quartz tube, and vacuum package the quartz tube using a hydrogen-oxygen machine. Place the vacuum-packaged quartz tube in a muffle furnace. By heating for 800 minutes, raise the temperature in the muffle furnace from room temperature to 900 °C, then keep it at 900 °C for 1580 minutes, and then cool it at a rate of 3 °C / h to 800 °C to obtain a lanthanum-aluminum solution inside the quartz tube.
[0063] S3. Post-treatment: After taking out the quartz tube cooled to 800 °C in step S2 from the muffle furnace, place it upside down in a centrifuge and centrifuge for 4 minutes. Then, take out the quartz tube from the centrifuge after it has cooled to room temperature. Open the quartz tube to take out the lanthanum-aluminum single crystal with metallic luster, and soak the lanthanum-aluminum single crystal in a diluted sodium hydroxide solution to remove the impurities on its surface, obtaining a high-quality lanthanum-aluminum single crystal, denoted as Sample 4.
[0064] Example 5
[0065] This example provides a lanthanum-aluminum single crystal, which is prepared by the following method:
[0066] S1. Weigh the raw materials: In a glove box filled with nitrogen, weigh lanthanum and aluminum in a molar ratio of 1:12 and place them in a crucible. After mixing lanthanum and aluminum evenly, place the crucible in a quartz tube. After stuffing quartz wool at the outlet of the quartz tube, take out the quartz tube from the glove box.
[0067] S2. Crystal growth: Install the quartz tube taken out in step S1 on the vacuum packaging device, extract the nitrogen inside the quartz tube, and vacuum-seal the quartz tube using a hydrogen-oxygen machine; place the vacuum-sealed quartz tube in a muffle furnace, heat it for 1100 min to raise the temperature in the muffle furnace from room temperature to 1000 °C, then keep it at 1000 °C for 1350 min, and then cool it to 700 °C at a cooling rate of 1.5 °C / h to obtain a lanthanum-aluminum solution inside the quartz tube.
[0068] S3. Post-treatment: After taking out the quartz tube cooled to 700 °C in step S2 from the muffle furnace, invert it in a centrifuge and centrifuge for 2 min, and then take it out of the centrifuge after the quartz tube has cooled to room temperature; open the quartz tube and take out the lanthanum-aluminum single crystal with metallic luster, soak the lanthanum-aluminum single crystal in a diluted sodium hydroxide solution to remove the impurities on its surface, and obtain a high-quality lanthanum-aluminum single crystal, denoted as sample 5.
[0069] Characterize and test the samples in the examples, and the results are as follows:
[0070] Grind the sample 1 prepared in Example 1 into powder and perform powder X-ray diffraction analysis. The results are as Figure 1 shown. The diffraction curve marked as the experimental result in the figure represents the XRD test result of sample 1 in Example 1, and the diffraction curve marked as the theoretical result in the figure represents the XRD diffraction curve of La3Al in the standard card; from 11 it can be observed that the positions of the XRD characteristic peaks of sample 1 are consistent with the peak positions of La3Al in the standard card Figure 1 , indicating that the sample 1 prepared in Example 1 is completely the La3Al 11 phase and there are no other impurity phases. 11
[0071] The micrograph of sample 1 prepared in Example 1 is as Figure 2 shown. Sample 1 is prismatic, about 5 mm in length, and has a complete crystal structure.
[0072] Perform energy spectrum tests on samples 1-5 prepared in the examples, and the results are shown in Table 1:
[0073] Table 1 Energy spectrum test results of samples 1-5
[0074]
[0075] The elemental energy spectrum diagram (EDS) of sample 1 is as Figure 3 shown, Figure 3 and the inset in Figure 3It can be seen that in each embodiment, the molar ratio of La and Al in the prepared lanthanum-aluminum single crystal is between 3:(11 - 11.3), and the average molar ratio of La and Al is 3:11.18, which is very close to the ideal value of La3Al 11 of 3:11, and there are no other impurities, having high quality.
[0076] The resistivity analysis tests were carried out on the lanthanum-aluminum single crystals prepared in Example 1 and Example 2, and the variation of the resistivity of the lanthanum-aluminum single crystal with temperature was characterized. The results are as Figure 4 shown. It can be seen that the lanthanum-aluminum single crystals prepared in Example 1 and Example 2 both exhibit metallic behavior. The resistivity of sample 1 prepared in Example 1 at 300 K is 25.8 μΩ·cm, and the resistivity at absolute zero is 0.11 μΩ·cm. It can be known that the residual resistivity ratio of sample 1 prepared in Example 1 is 235; while the resistivity of sample 2 prepared in Example 2 at 300 K is 30.7 μΩ·cm, and the resistivity at absolute zero is 0.3 μΩ·cm. It can be known that the residual resistivity ratio of sample 2 prepared in Example 2 is 103; the lanthanum-aluminum single crystals prepared in Example 1 and Example 2 both have relatively high residual resistivity ratios, and sample 1 has a higher residual resistivity ratio than sample 2.
[0077] The magnetoresistance performance tests were carried out on the lanthanum-aluminum single crystals prepared in Example 1 and Example 2, and the variation of the magnetoresistance of the lanthanum-aluminum single crystal with magnetic field at a temperature of 2 K was characterized. As Figure 5 shown. It can be seen that both sample 1 and sample 2 have relatively large magnetoresistance. The magnetoresistance of sample 1 reaches 8000%, while the magnetoresistance of sample 2 also reaches 3000%. Sample 1 has a higher magnetoresistance than sample 2.
[0078] The magnetic susceptibility tests were carried out on the lanthanum-aluminum single crystals prepared in Example 1 and Example 2, and the variation of the magnetic susceptibility of the lanthanum-aluminum single crystal with magnetic field at a temperature of 2 K was characterized. As Figure 6 shown. It can be seen that the magnetic susceptibility of sample 1 at 2 K shows obvious quantum oscillation behavior, while quantum oscillation cannot be observed in sample 2.
[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A lanthanum aluminum single crystal, characterized in that: The molar ratio of lanthanum to aluminum in the lanthanum aluminum single crystal is 3:(11-11.8), the residual resistivity ratio of the lanthanum aluminum single crystal is ≥235, and the magnetic resistance of the lanthanum aluminum single crystal at 2K is ≥8000%; The preparation method of the lanthanum aluminum single crystal comprises the following steps: S1. Weighing raw materials: weighing lanthanum and aluminum under a protective atmosphere, mixing them to obtain a mixed raw material, wherein the molar ratio of the lanthanum to the aluminum is ≤1:10; S2, crystal growth: the mixed raw material of step S1 is subjected to crystal growth under a vacuum environment, the holding temperature of the crystal growth is 900-1200 ° C, the holding time is more than 1200 min, and after the holding is completed, the temperature is lowered step by step, and the step-by-step cooling process is to lower the temperature to 900-950 ° C at a cooling rate of ≤3 ° C / h, then increase the temperature to 1100-1150 ° C at a heating rate of 3-5 ° C / min, and then lower the temperature to 700-800 ° C at a cooling rate of ≤3 ° C / h to obtain a lanthanum aluminum solution; S3, post-processing: the lanthanum aluminum solution in step S2 is post-processed to obtain lanthanum aluminum single crystals.
2. The lanthanum aluminum single crystal according to claim 1, characterized in that The length of the lanthanum aluminum single crystal is ≥0.1 mm.
3. The lanthanum aluminum single crystal according to claim 1, characterized in that The magnetic susceptibility of the lanthanum aluminum single crystal at 2K shows a quantum oscillation effect.
4. The lanthanum aluminum single crystal according to claim 1, characterized in that The process of weighing the raw materials in step S1 is carried out in a glove box; And / or, the protective atmosphere in step S1 is at least one of nitrogen and argon; And / or, the molar ratio of the lanthanum to the aluminum in step S1 is 1:(11-15).
5. The lanthanum aluminum single crystal according to claim 1, characterized in that: The specific process of step S1 is: in a glove box with a protective atmosphere, the lanthanum and the aluminum are weighed according to the molar ratio and placed in a container. After the lanthanum and the aluminum are evenly mixed, the outlet of the container is plugged with quartz wool and taken out from the glove box.
6. The lanthanum aluminum single crystal according to claim 1, characterized in that: The time for the mixed raw material to rise from room temperature to the insulation temperature in step S2 is 800-1200 min; And / or, the post-treatment in step S3 includes centrifugal treatment, quenching and flux removal.
7. The lanthanum aluminum single crystal according to claim 1, characterized in that: The process of forming the vacuum environment in step S2 is as follows: placing the mixed raw material in step S1 in a sealed container with a protective atmosphere, extracting the protective gas in the sealed container, and vacuum-sealing the mixed raw material in the sealed container using a high-temperature flame in conjunction with a vacuum pump.
8. The lanthanum aluminum single crystal according to claim 6, characterized in that: The temperature of the centrifugal treatment is 700-800°C; And / or, the rotation speed of the centrifugal treatment is ≥2500 r / min; And / or, the flux removal uses a sodium hydroxide solution.
9. Application of the lanthanum aluminum single crystal as described in any one of claims 1 to 3 in the fields of storage, sensor, quantum computing or quantum communication.