阅读说明：本技术 一种具有反常霍尔效应的材料及其制备方法和应用 (Material with abnormal Hall effect and preparation method and application thereof ) 是由 刘恩克 申建雷 王文洪 郗学奎 吴光恒 于 2021-05-27 设计创作，主要内容包括：本发明提供一种具有反常霍尔效应的材料及其制备方法和应用,其化学式为：Co-(3-a)X-(a)Sn-(2-)-(b)Y-(b)S-(2-c)Z-(c),其中,X选自Cu、Ni、Fe、Mn、Cr、V和Ti中的一种或多种,Y选自Al、Ga、In、Si、Ge、Pb和Sb中的一种或多种,Z选自Se、Te和P中的一种或多种,0≤a≤2,0≤b≤2,0≤c≤2,并且0<a+b+c<6,其中,当X为Ni时,b和c不同时为0；当Y为In时,a和c不同时为0；当Z为Se时,a和b不同时为0。本发明提供的材料是一系列不同元素取代的磁性外尔半金属,通过各种机制可实现该类材料的反常霍尔参数的优化和连续可调。其中,横向电流转换效率即反常霍尔角比常规的磁性材料高1-2个数量级。因此该材料在磁性传感器、磁随机储存器、自旋转移力矩等自旋电子学器件方面有广泛的应用前景。(The invention provides a material with abnormal Hall effect, a preparation method and application thereof, wherein the chemical formula is as follows: co 3‑a X a Sn 2‑ b Y b S 2‑c Z c Wherein X is selected from one or more of Cu, Ni, Fe, Mn, Cr, V and Ti, Y is selected from one or more of Al, Ga, In, Si, Ge, Pb and Sb, Z is selected from one or more of Se, Te and P, a is more than or equal to 0 and less than or equal to 2, b is more than or equal to 0 and less than or equal to 2, c is more than or equal to 0 and less than or equal to 2, and 0 is more than or equal to 0 and less than or equal to 2<a+b+c<6, wherein when X is Ni, b and c are not 0 at the same time; when Y is In, a and c are not 0 at the same time; when Z is Se, a and b are not 0 at the same time. The material provided by the invention is a series of magnetic pheromone semimetals substituted by different elements, and the abnormal Hall parameters of the material can be optimized and continuously adjusted through various mechanisms. Wherein the transverse current conversion efficiency, i.e. the abnormal hall angle, is 1-2 orders of magnitude higher than that of conventional magnetic materials. Therefore, the material has wide application prospect in the aspects of spintronics devices such as magnetic sensors, magnetic random access memories, spin transfer torque and the like.)

1. A material having an abnormal hall effect, having the formula: co_3-aX_aSn_2-bY_bS_2-cZ_cWherein X is selected from one or more of Cu, Ni, Fe, Mn, Cr, V and Ti, Y is selected from one or more of Al, Ga, In, Si, Ge, Pb and Sb, Z is selected from one or more of Se, Te and P, a is more than or equal to 0 and less than or equal to 2, b is more than or equal to 0 and less than or equal to 2, c is more than or equal to 0 and less than or equal to 2, and 0 is more than or equal to 0 and less than or equal to 2<a+b+c<6, wherein when X is Ni, b and c are not 0 at the same time; when Y is In, a and c are not 0 at the same time; when Z is Se, a and b are not 0 at the same time.

2. The material of claim 1, wherein 0 ≦ a ≦ 1, 0 ≦ b ≦ 1, 0 ≦ c ≦ 1, and 0< a + b + c ≦ 2.

3. The material of claim 1 or 2, wherein the material is a monocrystalline bulk material; preferably, the material has an anomalous hall angle at zero field of 21% to 35%.

4. A method of making a material having an abnormal hall effect, the method comprising:

(1) according to the chemical formula Co_3-aX_aSn_2-bY_bS_2-cZ_cWeighing raw materials, wherein X is selected from one or more of Cu, Ni, Fe, Mn, Cr, V and Ti, Y is selected from one or more of Al, Ga, In, Si, Ge, Pb and Sb, Z is selected from one or more of Se, Te and P, a is more than or equal to 0 and less than or equal to 2, b is more than or equal to 0 and less than or equal to 2, c is more than or equal to 0 and less than or equal to 2, and 0 and less than or equal to 2<a+b+c<6, wherein when X is Ni, b and c are not 0 at the same time; when Y is In, a and c are not 0 at the same time; when Z is Se, a and b are not 0 simultaneously;

(2) preparing the raw materials into single crystal materials by adopting a fluxing agent method, a slow cooling method or a chemical vapor transport method.

5. The method of claim 4, wherein step (1) comprises weighing raw materials in a molar ratio of (Co + X) Sn (S + Z) Pb 12:35:8:45, or in a stoichiometric ratio of (Co + X) Sn + Y (S + Z) 3:2: 2.

6. The production method according to claim 4, wherein the flux used In the flux method is selected from one or more of Pb, Sn, PbSn, Al, and In.

7. The method of claim 4, wherein the slow cooling method comprises the steps of:

heating the raw materials to 350-450 ℃ for 3-5 hours after 8-12 hours, heating to 1000-1100 ℃ for 5-8 hours after 8-12 hours, and then cooling to room temperature after 20-30 hours;

grinding the product into powder and then carrying out secondary firing, wherein the secondary firing comprises the following temperature period of 2-5 times: heating for 8-12 hours to 350-450 ℃, keeping for 3-5 hours, heating for 8-12 hours to 1000-1100 ℃, keeping for 5-8 hours, cooling for 5-8 hours to 600-800 ℃, and heating for 1-4 hours to 1000-1100 ℃;

and cooling the product to 600-800 ℃ for 6-10 days, preserving the heat for 2-5 days, and naturally cooling to room temperature.

8. The production method according to claim 4, wherein the chemical vapor transport method comprises the steps of:

heating the raw materials to 350-450 ℃ for 3-5 hours after 8-12 hours, heating to 1000-1100 ℃ for 5-8 hours after 8-12 hours, and then cooling to room temperature after 20-30 hours;

grinding the product into powder, sealing the raw materials in a quartz tube, placing the quartz tube in a double-temperature-zone tube furnace, and firing: setting a reverse temperature field: the raw material end is 780-820 ℃, the growth end is 880-920 ℃, and the temperature is set to be a forward temperature field degree after firing for 36-72 hours: the raw material end is 840-860 ℃, the growing end is 780-820 ℃, and the temperature is naturally reduced to the room temperature after the raw material end and the growing end are fired for 20-40 days.

9. Use of a material with abnormal hall effect according to any of claims 1 to 3 or a material with abnormal hall effect produced according to the method of any of claims 4 to 8 in spintronics.

10. Use according to claim 9, wherein the spintronics device comprises a magnetic sensor, a magnetic random access memory and a spin transfer torque.

Technical Field

The invention relates to a magnetic topological semi-metal material, in particular to a material with an abnormal Hall effect under a zero field, and a preparation method and application thereof.

Background

The phenomenon that carriers of metal conductors and semiconductors electrified in a magnetic field are subjected to lorentz force to generate a transverse potential difference is called hall effect. A phenomenon in which a potential difference in the transverse direction can be generated even in the absence of a magnetic field in a ferromagnetic material is called an abnormal hall effect. The abnormal hall effect generally comprises two microscopic mechanisms, one is related to the bery curvature distribution of the band structure of the material, which is called an intrinsic mechanism; the other is the intrinsic mechanism associated with the asymmetric scattering of carriers by impurities. The application of abnormal hall effects often requires a larger abnormal hall angle, i.e. a larger lateral current conversion efficiency.

It has been found through a number of experiments and theoretical calculations that large anomalous hall effects tend to result from the intrinsic mechanism, i.e., the material with topologically enhanced bery curvature. The band structures of these materials often have an outlier or an open pitch loop, and these special band structures induce a strong bery curvature to bring a huge intrinsic hall conductance. This has led to the search for large anomalous hall effect materials looking to be diverted to such topological magnetic materials. Such as magnetic epi-semimetal Co₃Sn₂S₂Due to the presence of 3 opposite-handedness weiler points and open nodal loops near the fermi surface, a strong bery curvature distribution is shown near the fermi level, so that the material shows a huge abnormal hall effect (an abnormal hall conductance of 1130S/cm and an abnormal hall angle of 20%), which is much larger than that of the traditional material and even all current topological materials. It is worth mentioning that the Co is used₃Sn₂S₂The saturation field of the material is very low and has coercive force, so that the material can show the large abnormal Hall effect under the condition of zero field, and the practical application of the material is also greatly facilitated. In addition to this, other magnetic topological materials such as Co₂MnGa/Al、Fe₃GeTe₂Etc. also exhibit a large anomalous hall effect due to their topologically enhanced bery curvature.

Practical applications and device designs based on abnormal hall effects often need to meet different requirements, which requires that abnormal hall effect materials have continuously adjustable physical properties and a wide variety of candidate materials.

Disclosure of Invention

Therefore, the invention aims to provide a series of magnetic exol semimetals substituted by different elements, and realize the optimization and continuous adjustment of abnormal Hall parameters of the materials through various mechanisms.

The invention provides a material with an abnormal Hall effect, which has a chemical formula as follows: co_3-aX_aSn_2-bY_bS_2-cZ_cWherein X is selected from one or more of Cu, Ni, Fe, Mn, Cr, V and Ti, and Y is selected from Al, Ga, In, Si,Ge. One or more of Pb and Sb, Z is selected from one or more of Se, Te and P, a is 0-2, b is 0-2, c is 0-2, and 0<a+b+c<6, wherein when X is Ni, b and c are not 0 at the same time; when Y is In, a and c are not 0 at the same time; when Z is Se, a and b are not 0 at the same time.

According to the material having an abnormal Hall effect of the present invention, preferably, 0. ltoreq. a.ltoreq.1, 0. ltoreq. b.ltoreq.1, 0. ltoreq. c.ltoreq.1, and 0< a + b + c.ltoreq.2.

The material having an abnormal hall effect according to the present invention is preferably a single crystal bulk material.

The material having an abnormal hall effect according to the present invention preferably has an abnormal hall angle of 21 to 35% at zero field.

The invention also provides a preparation method of the material with the abnormal Hall effect, which comprises the following steps:

(1) according to the chemical formula Co_3-aX_aSn_2-bY_bS_2-cZ_cWeighing raw materials, wherein X is selected from one or more of Cu, Ni, Fe, Mn, Cr, V and Ti, Y is selected from one or more of Al, Ga, In, Si, Ge, Pb and Sb, Z is selected from one or more of Se, Te and P, a is more than or equal to 0 and less than or equal to 2, b is more than or equal to 0 and less than or equal to 2, c is more than or equal to 0 and less than or equal to 2, and 0 and less than or equal to 2<a+b+c<6, wherein when X is Ni, b and c are not 0 at the same time; when Y is In, a and c are not 0 at the same time; when Z is Se, a and b are not 0 at the same time.

(2) Preparing the raw materials into single crystal materials by adopting a fluxing agent method, a slow cooling method or a chemical vapor transport method.

The preparation method provided by the invention is characterized in that the step (1) comprises the steps of weighing raw materials according to a molar ratio of (Co + X) to Sn (S + Z) to Pb (12: 35:8: 45), or according to a stoichiometric ratio of (Co + X) to (Sn + Y) to (S + Z) to 3:2: 2.

According to the preparation method provided by the invention, the fluxing agent used In the fluxing agent method is selected from one or more of Pb, Sn, PbSn, Al and In.

According to the preparation method provided by the invention, the slow cooling method can comprise the following steps:

heating the raw materials to 350-450 ℃ for 3-5 hours after 8-12 hours, heating to 1000-1100 ℃ for 5-8 hours after 8-12 hours, and then cooling to room temperature after 20-30 hours;

grinding the product into powder and then carrying out secondary firing, wherein the secondary firing comprises the following temperature period of 2-5 times: heating for 8-12 hours to 350-450 ℃, keeping for 3-5 hours, heating for 8-12 hours to 1000-1100 ℃, keeping for 5-8 hours, cooling for 5-8 hours to 600-800 ℃, and heating for 1-4 hours to 1000-1100 ℃;

and cooling the product to 600-800 ℃ for 6-10 days, preserving the heat for 2-5 days, and naturally cooling to room temperature.

According to the preparation method provided by the invention, the chemical vapor transport method comprises the following steps:

heating the raw materials to 350-450 ℃ for 3-5 hours after 8-12 hours, heating to 1000-1100 ℃ for 5-8 hours after 8-12 hours, and then cooling to room temperature after 20-30 hours;

grinding the product into powder, sealing the raw materials in a quartz tube, placing the quartz tube in a double-temperature-zone tube furnace, and firing: setting a reverse temperature field: the raw material end is 780-820 ℃, the growth end is 880-920 ℃, and the temperature is set to be a forward temperature field degree after firing for 36-72 hours: the raw material end is 840-860 ℃, the growing end is 780-820 ℃, and the temperature is naturally reduced to the room temperature after the raw material end and the growing end are fired for 20-40 days.

The invention also provides the application of the material with the abnormal Hall effect in a spintronics device. The spintronics device includes a magnetic sensor, a magnetic random access memory, and a spin transfer torque.

The material and the preparation method thereof provided by the invention have the following beneficial effects:

1. the invention provides a material (Co) with abnormal Hall effect_3-aX_aSn_2-bY_bS_2-cZ_cMagnetic topological material) having a Weyl point and pitch ring protected by momentum space topology, the strong bery curvature imparted by these topological band structures causes the material to exhibit a number of physical characteristics associated therewithIn particular, the material shows huge intrinsic abnormal Hall effect, wherein the abnormal Hall conductance, the abnormal Hall angle and the abnormal Hall factor are 1 to 2 orders of magnitude higher than those of the traditional magnetic material. Due to the energy band structure of the topological protection, the large intrinsic anomalous Hall effect can be kept in a wide temperature range. On the other hand, the micro doping of the hetero atoms can enhance the extrinsic hall effect, thereby further enhancing the abnormal hall effect. The application prospect of the material is greatly improved.

2. The material with the abnormal Hall effect provided by the invention has the advantages that the magnetism and the electric property can be continuously adjusted and the excellent abnormal Hall characteristic can be continuously shown along with the difference of doping elements and doping amount. According to the design requirements of different application devices, a rich candidate material can be provided. The required raw materials are transition group and main group elements which are low in price, rich in reserves and easy to store, and the commercial application of the materials is facilitated.

3. The preparation method of the material adopts conventional muffle furnace, tube furnace and other equipment, does not need other additional equipment, and has the advantages of simple and reliable preparation process, good process stability and easy industrial production. The chemical property of the material is stable, and the material can be highly stable in air, alcohol, acetone, strong alkali, boiled water and other environments.

4. The material provided by the invention has strong Belley curvature caused by a topological energy band structure, so that the material has a plurality of excellent physical properties related to the material, including abnormal Hall effect, Nernst effect, magneto-optical Kerr effect, exchange bias effect and the like, and quantum abnormal Hall effect under a two-dimensional limit, particularly huge abnormal Hall effect, so that the material has wide application, such as Hall sensors, sensors based on rotation transmission torque and the like.

Drawings

Embodiments of the invention are described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 shows Co obtained in example 10 of the present invention_2.9Ni_0.1Sn_1.8In_0.2S_1.7Se_0.3Single crystal X of materialAn RD map;

FIG. 2 shows Co obtained in example 9 of the present invention_2.9Ni_0.1Sn_1.8In_0.2S₂Longitudinal resistivity-temperature curve of the material;

FIG. 3 shows Co obtained in example 5 of the present invention_2.95Ni_0.05Sn₂S_1.9Te_0.1Isothermal magnetization curve of the material;

FIG. 4 shows Co obtained in example 8 of the present invention_2.9Fe_0.1Sn_1.8Sb_0.2S₂The hall angle versus magnetic field curve of the material;

FIG. 5 shows Co obtained in example 1 of the present invention_2.9Cr_0.1Sn₂S₂The thermomagnetic curve of the material;

FIG. 6 shows Co obtained in example 5 of the present invention_2.95Ni_0.05Sn₂S_1.9Te_0.1A hall conductivity-magnetic field curve of the material;

FIG. 7 shows Co obtained in example 6 of the present invention₃Sn_1.4Sb_0.6S₂Hall angle versus temperature curve of the material.

Detailed Description

The present invention is described in further detail below with reference to specific embodiments, which are given for the purpose of illustration only and are not intended to limit the scope of the invention.

In each of the following examples, the inventors measured isothermal magnetization curve, hall curve, magnetoresistance curve, magnetocaloric effect curve, magnetic strain curve, and single crystal and powder X-ray diffraction patterns of the obtained samples, respectively, to show the relevant characteristics of the materials to which the present invention relates. But for simplicity only the results are shown for several of the samples, with similar results for the corresponding properties of the other samples.

Example 1

This example preparation has a composition of Co_2.9Cr_0.1Sn₂S₂The preparation method of the magnetic exol semimetal material with the abnormal Hall effect comprises the following steps:

(1) raw materials with the purity of 99.99 percent are weighed according to the molar ratio of Co to Cr to Sn to S to Pb of 11.6 to 0.4 to 35 to 8 to 45, and the total weight is 20 g.

(2) The weighed raw materials are put into an alumina crucible with a filter sieve at 10^-4Below Pa it was sealed in a quartz tube, which was then placed vertically in a muffle furnace.

Growth of Co by flux method_2.9Cr_0.1Sn₂S₂Single crystal: firstly, heating a quartz tube in a muffle furnace to 400 ℃ for 4 hours after 10 hours; heating to 1050 deg.C for another 10 hr for 6 hr; then the temperature is reduced to 700 ℃ after 6 hours, and then the temperature is heated to 1050 ℃ after 2 hours, and the temperature is reduced to 700 ℃ after 3 times of oscillation process and is kept for 3 days. Keeping the temperature at 700 ℃ for 3 days, quickly taking out the quartz tube, inverting the quartz tube, putting the quartz tube into a centrifuge, starting the centrifuge to throw out the redundant fluxing agent through a filter sieve, and finally obtaining Co_2.9Cr_0.1Sn₂S₂The single crystal sample of (1).

Measuring the resulting Co_2.9Cr_0.1Sn₂S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Wherein, under a 100Oe magnetic field, a PPMS type comprehensive physical property measurement system of United states QD company is adopted to obtain Co_2.9Cr_0.1Sn₂S₂The thermal magnetization curve of the material shows that the ferromagnetic characteristic of the material has the Curie temperature of 168K. At 10K, using a comprehensive physical property measurement system of the PPMS type of the QD company, usa, a hall curve of the material was obtained, which exhibited a huge abnormal hall conductivity of 1510S/cm and a huge abnormal hall angle of 22.5% at zero field.

Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

Example 2

This example preparation has a composition of Co_2.8Mn_0.2Sn₂S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

(1) 5g of raw materials with the purity of 99.99 percent are weighed according to the stoichiometric ratio of Co to Mn to Sn to S of 2.8 to 0.2 to 2.

(2) The weighed raw materials are put into a graphite crucible with a clean function at 10 DEG^-4Below Pa it was sealed in a quartz tube, which was then placed vertically in a muffle furnace.

Growing Co by solid solution reaction method_2.8Mn_0.2Sn₂S₂Polycrystalline body: firstly, heating the quartz tube in the muffle furnace to 400 ℃ for 4 hours after 10 hours, and then heating to 1050 ℃ for 6 hours after 10 hours; after that, the temperature was decreased to room temperature over 1 day.

Taking out the above polycrystalline sample, grinding into powder, taking 0.5g sample, and filtering at 10 deg.C^-4Pa or less, it was sealed in a quartz tube having a length of 15 cm. The second sealed quartz tube is placed horizontally in a dual temperature zone tube furnace with the feedstock section placed at one of the heating sources. Set up reverse temperature field 800 ℃ (raw materials end) -900 ℃ (growth end earlier, through the reverse temperature field of 2 days, set up the forward temperature field degree 850 ℃ (raw materials end) -800 ℃ (growth end) that the temperature set up to normal rising after that, through 30 days. And then closing the furnace body with the double temperature zones, and naturally cooling to room temperature to obtain a single crystal sample.

Measuring the resulting Co_2.8Mn_0.2Sn₂S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

Example 3

This example preparation has a composition of Co_2.85Fe_0.15Sn₂S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

(1) the raw materials having a purity of 99.99% were weighed in a molar ratio of Co, Fe, Sn, S, Pb of 11.4:0.6:35:8:45 to give 20g, and the rest was the same as in example 1.

Measuring the resulting Co_2.85Fe_0.15Sn₂S₂Various physical properties of the single crystal, and collectingVarious characteristic parameters thereof. Wherein, at 10K, a PPMS type comprehensive physical property measurement system of the United states QD company is adopted to obtain a Hall curve of the material, and the material shows huge abnormal Hall conductivity 1183S/cm and huge Hall angle 33% under zero field.

Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

Example 4

This example preparation has a composition of Co_2.9Cu_0.1Sn₂S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

the procedure of example 1 was repeated except that 20g of the raw materials having a purity of 99.99% were weighed in a molar ratio of Co, Cu, Sn, S, and Pb of 11.6:0.4:35:8: 45.

Measuring the resulting Co_2.9Cu_0.1Sn₂S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Wherein table 1 shows curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for the material.

Example 5

This example preparation has a composition of Co_2.95Ni_0.05Sn₂S_1.9Te_0.1The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

the same procedures as in example 1 were repeated except that 20g of the raw materials having a purity of 99.99% were weighed in such a molar ratio that Co, Ni, Sn, S, Te and Pb were added to 20.8, 0.2, 35, 7.6, 0.4 and 45, respectively.

Measuring the resulting Co_2.95Ni_0.05Sn₂S_1.9Te_0.1Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Wherein table 1 shows curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for the material.

Example 6

This example preparation has a composition of Co₃Sn_1.4Sb_0.6S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

(1) the raw materials with the purity of 99.99 percent are weighed according to the stoichiometric proportion of Co, Sn, Sb, S and Pb of 3, 1.4, 0.6 and 2, and the total weight is 5 g.

(2) The weighed raw materials are put into a graphite crucible with a clean function at 10 DEG^-4Below Pa it was sealed in a quartz tube, which was then placed vertically in a muffle furnace.

Co growth by slow cooling method₃Sn_1.4Sb_0.6S₂Single crystal: the quartz tube in the muffle furnace was first heated to 400 ℃ for 4 hours over 10 hours, then heated to 1050 ℃ for 6 hours over another 10 hours, and thereafter cooled to room temperature over 1 day. Taking out the sample, grinding into powder, and adding the powder at 10^-4Pa or less is sealed in the quartz tube. The second sealed quartz tube was heated to 400 c for 4 hours over a 10 hour period and then to 1050 c for 6 hours over a 10 hour period. Then, after 6 hours, the temperature is reduced to 700 ℃, then the temperature is heated to 1050 ℃ after 2 hours, the temperature oscillation process is carried out for 3 times, then the temperature is reduced to 700 ℃ after a week, the temperature is preserved for 3 days, and then the muffle furnace is closed to naturally cool the muffle furnace to the room temperature. Finally obtaining Co₃Sn_1.4Sb_0.6S₂The single crystal sample of (1).

Measuring the resulting Co₃Sn_1.4Sb_0.6S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

Example 7

This example preparation has a composition of Co₃Sn_1.9Ge_0.1S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

the procedure is as in example 6 except that 20g of the raw materials having a purity of 99.99% are weighed in a molar ratio of Co to Sn to Ge to S to Pb of 3 to 1.9 to 0.1 to 2.

Measuring the resulting Co₃Sn_1.9Ge_0.1S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Wherein table 1 shows curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for the material.

Example 8

This example preparation has a composition of Co_2.9Fe_0.1Sn_1.8Sb_0.2S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

the same procedures as in example 6 were repeated except that 10g of the starting materials having a purity of 99.99% were weighed in a molar ratio of Co, Fe, Sn, Sb and S of 2.9:0.1:1.8:0.2: 2.

Measuring the resulting Co_2.9Fe_0.1Sn_1.8Sb_0.2S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Wherein table 1 shows curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for the material.

Example 9

This example preparation has a composition of Co_2.9Ni_0.1Sn_1.8In_0.2S₂The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

the raw materials with a purity of 99.99% were weighed to total 10g In stoichiometric ratio of Co, Ni, Sn, In, and S of 2.9:0.1:1.8:0.2:2, and the rest was the same as In example 6.

Measuring the resulting Co_2.9Ni_0.1Sn_1.8In_0.2S₂Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

Example 10

This example preparation has a composition of Co_2.9Ni_0.1Sn_1.8In_0.2S_1.7Se_0.3The preparation method of the magnetic exol semimetal material with huge abnormal Hall effect comprises the following steps:

raw materials with a purity of 99.99% were weighed In a stoichiometric ratio of Co, Ni, Sn, In, S, and S of 2.9:0.1:1.8:0.2:1.7:0.3 to give 10g In total, and the rest was the same as In example 6.

Measuring the resulting Co_2.9Ni_0.1Sn_1.8In_0.2S_1.7Se_0.3Various physical characteristics of the single crystal and various characteristic parameters thereof are collected. Table 1 shows the curie temperature, saturation magnetic moment, residual resistivity, abnormal hall conductivity, and abnormal hall angle for this material.

TABLE 1