阅读说明：本技术 一种用于磁光克尔测量仪器的磁场发生装置 (Magnetic field generating device for magneto-optical Kerr measuring instrument ) 是由 张学莹 王麟 赵巍胜 欧阳玉东 于 2019-10-12 设计创作，主要内容包括：本发明提出一种用于磁光克尔测量仪器的磁场发生装置,包括：至少一个磁极、导磁板、至少一个导磁柱、导磁底座、励磁线圈及励磁线圈供电单元,所述磁极一端固定在导磁底座上,磁极另一端上方设置导磁板,导磁柱一端与导磁底座固定,另一端与导磁板固定,励磁线圈缠绕在磁极表面,励磁线圈供电单元与励磁线圈相连接,为励磁线圈提供电流。本发明通过导磁板、导磁柱、磁极等的导磁作用,减少了磁势的损失,从而允许向样品施加较大的磁场,通过试验,能够达到1T以上,且导磁板留有通孔,可以允许光线通过,因此,在导磁板的上方可以布设光路,并达到了磁光克尔测量系统测试的要求,即磁场与光线入射方向平行。(The invention provides a magnetic field generating device for a magneto-optical Kerr measuring instrument, which comprises: the magnetic pole power supply unit is connected with the excitation coil and supplies current to the excitation coil. The invention reduces the loss of magnetic potential through the magnetic conduction effect of the magnetic conduction plate, the magnetic conduction column, the magnetic pole and the like, thereby allowing a larger magnetic field to be applied to a sample, and the magnetic field can reach more than 1T through the test, and the magnetic conduction plate is provided with the through hole for allowing light to pass through, therefore, a light path can be arranged above the magnetic conduction plate, and the test requirement of a magneto-optical Kerr measurement system is met, namely, the magnetic field is parallel to the incident direction of the light.)

1. A magnetic field generating device for a magneto-optical kerr measuring instrument, comprising: at least one magnetic pole, magnetic conduction board, at least one magnetic conduction post, magnetic conduction base, excitation coil and excitation coil power supply unit, its characterized in that:

one end of the magnetic pole is fixed on the magnetic conduction base, a magnetic conduction plate is arranged above the other end of the magnetic pole, one end of the magnetic conduction column is fixed with the magnetic conduction base, the other end of the magnetic conduction column is fixed with the magnetic conduction plate, the excitation coil is wound on the surface of the magnetic pole, and the excitation coil power supply unit is connected with the excitation coil and supplies current to the excitation coil;

the magnetic conduction plate is provided with a light through hole.

2. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein: the magnetic poles and the magnetic conduction plates form magnetic conduction paths through the magnetic conduction bases and the magnetic conduction columns.

3. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein: the magnetic conducting columns can be replaced by magnetic conducting walls, which are cylindrical magnetic walls surrounding the magnetic poles.

4. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

the magnetic pole, the magnetic conduction plate, the magnetic conduction column and the magnetic conduction base are integrally processed, or the magnetic pole, the magnetic conduction plate, the magnetic conduction column and the magnetic conduction base are spliced and processed.

5. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

and a dismounting structure is arranged at the joint of the magnetic conduction column or the magnetic conduction column and the magnetic conduction plate, so that the magnetic conduction plate can be dismounted from the magnetic conduction column.

6. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

the magnetic poles, the magnetic conduction plates, the magnetic conduction bases and the magnetic conduction columns are all made of ferromagnetic or ferrimagnetic substances.

7. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

the thickness of the magnetic conduction plate is between 1mm and 10 cm.

8. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1 or claim 3, wherein:

the outer surface of the magnetic conduction column or the magnetic conduction wall is wound by the excitation coil, and the excitation coil power supply unit supplies current to the excitation coil.

9. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

if the magnetic field generating device is used in combination with an imaging system with an objective lens, the thickness of the magnetic conducting plate at the position corresponding to the magnetic pole cannot exceed the focal length of the objective lens, wherein the objective lens is placed above the light through hole of the magnetic field generating device.

10. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument as claimed in claim 1, wherein:

the magnetic poles are columnar.

The technical field is as follows:

the invention belongs to the technical field of test and measurement, and particularly relates to a magnetic field generating device for a magneto-optical Kerr measuring instrument.

Background art:

the magneto-optical kerr measurement system is a system for optically characterizing the magnetization state of a magnetic sample by using the magneto-optical kerr effect. The application of a strong, relatively uniform magnetic field around a test sample is a common test condition used during the testing of magnetic samples. An electromagnet with an iron core structure is a common device for generating a uniform strong magnetic field. The core is a structure for magnetic conduction, which contains magnetic elements such as cobalt, nickel, and iron in the magnet structure. Conventional electromagnets are typically provided with one, two or three pairs of symmetrical poles, with symmetrical field coils positioned adjacent the poles. In this configuration, the magnetic field generated by a pair of magnetized magnetic poles is perpendicular to the pole faces of the magnetic poles, and the magnetic field strength is inversely proportional to the distance of the opposing magnetic poles, and the magnetic field uniformity decreases with increasing distance of the magnetic poles. Therefore, in order to obtain a large and uniform magnetic field, the distance facing the magnetic poles should be as small as possible. Although the electromagnet of the above type can generate a large magnetic field, it has problems in the magneto-optical measurement process, for example, when the change of the magnetization state of the sample with the vertical magnetic field is measured by using the polo-magneto kerr effect, it is necessary to inject light from the direction perpendicular to the measured surface of the sample, and at the same time, it is necessary to apply a magnetic field perpendicular to the sample surface, that is, the magnetic field is parallel to the incident direction of the light. At this time, the measured surface of the sample needs to be parallel to the magnetic pole surface. Due to the blocking effect of the magnetic pole on light, in this case, it is difficult to obtain normal incidence light to achieve measurement of the poloidal magneto-optical kerr effect. Although, some solutions have been proposed to partially solve this problem. For example, fig. 5 refers to a solution (US Patent No.: US9348000B 1): the magnet has a pair of magnetic poles, and 2 excitation coils surround 2 magnetic poles outsides, and a hole is punched on one magnetic pole, so that incident and reflected light rays pass through the magnetic poles from the hole, and magneto-optical measurement is realized. However, in this structure, a space for the magnetic pole and the excitation coil is required to be provided between the optical path element and the sample to be measured, and therefore, the structure is only suitable for an application apparatus in which the optical path element is far from the sample to be measured. For devices requiring the optical path element to be close to the sample, the above solution is no longer applicable, for example, when using a magneto-optical kerr microscope to perform magneto-optical imaging on the sample, the microscope system needs to be equipped with an objective lens or a convex lens (group), and the sample is at a small distance from the objective lens or the lens, which is not enough to accommodate the magnetic pole and the excitation coil as shown in the figure, so that the above magnet system cannot be close to the magneto-optical kerr microscope or other measuring devices requiring the optical element to be close to the sample.

The invention content is as follows:

the invention provides a magnetic field generating device for a magneto-optical Kerr measuring instrument, aiming at solving the problem that an electromagnet is not compatible with a magneto-optical Kerr measuring optical path in space. The electromagnet structural configuration provided by the invention can obtain a larger uniform magnetic field, and allows the optical element in the test light path to have a closer distance with the tested sample, so that the magneto-optical test requirement is met under the larger magnetic field.

A magnetic field generating device for a magneto-optical kerr measurement system, comprising: the magnetic pole comprises at least one magnetic pole, a magnetic conduction plate, at least one magnetic conduction column, a magnetic conduction base, an excitation coil and an excitation coil power supply unit;

one end of the magnetic pole is fixed on the magnetic conduction base, a magnetic conduction plate is arranged above the other end of the magnetic pole, one end of the magnetic conduction column is fixed with the magnetic conduction base, the other end of the magnetic conduction column is fixed with the magnetic conduction plate, the excitation coil is wound on the surface of the magnetic pole, and the excitation coil power supply unit is connected with the excitation coil and supplies current to the excitation coil;

the magnetic conduction plate is provided with a light through hole.

The magnetic poles and the magnetic conduction plates form magnetic conduction paths through the magnetic conduction bases and the magnetic conduction columns.

The magnetic conducting columns can be replaced by magnetic conducting walls, which are cylindrical magnetic walls surrounding the magnetic poles.

The magnetic pole, the magnetic conduction plate, the magnetic conduction column and the magnetic conduction base are processed integrally, or the magnetic pole, the magnetic conduction plate, the magnetic conduction column and the magnetic conduction base are spliced and processed;

and a dismounting structure is arranged at the joint of the magnetic conduction column or the magnetic conduction column and the magnetic conduction plate, so that the magnetic conduction plate can be dismounted from the magnetic conduction column.

The magnetic poles, the magnetic conduction plates, the magnetic conduction bases and the magnetic conduction columns are made of ferromagnetic or ferrimagnetic substances.

The thickness of the magnetic conduction plate is between 1mm and 10 cm.

The outer surface of the magnetic conduction column or the magnetic conduction wall is wound by the excitation coil, and the excitation coil power supply unit supplies current to the excitation coil.

If the magnetic field generating device is used in combination with an imaging system with an objective lens, the thickness of the magnetic conducting plate at the position corresponding to the magnetic pole cannot exceed the focal length of the objective lens, wherein the objective lens is placed above the light through hole of the magnetic field generating device.

The magnetic poles are columnar.

The beneficial technical effects are as follows:

the invention provides a magnetic field generating device for a magneto-optical Kerr measuring instrument. Through the magnetic conduction effect of the magnetic conduction plate, the magnetic conduction column, the magnetic poles and the like, the loss of magnetic potential is reduced, so that a larger magnetic field is allowed to be applied to a sample, and the magnetic field can reach more than 1T through tests. In addition, the magnetic conduction plate is provided with a through hole for allowing light to pass through, so that a light path can be arranged above the magnetic conduction plate, and the requirement of testing of a magneto-optical Kerr measurement system is met, namely the magnetic field is basically parallel to the incident direction of the light. The thickness of the magnetic conductive plate can be determined according to the requirement. The thickness of the magnetic conductive plate is reduced to be within the focal length of the objective lens, and the magnet system can be used for optical microscope imaging.

Description of the drawings:

FIG. 1 is a front view of a magnetic field generating device for a magneto-optical Kerr measuring instrument according to an embodiment of the present invention;

FIG. 2 is a front view of a magnetic field generating device for a magneto-optical Kerr measuring instrument in a removable configuration, in accordance with an embodiment of the present invention;

FIG. 3 is a top view of a magnetic field generating device for a magneto-optical Kerr measuring instrument according to an embodiment of the present invention;

FIG. 4 is a front view of a magnetic field generating device for a magneto-optical Kerr measuring instrument with an optical module according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a reference scheme in the background art;

in the figure: 1-magnetic pole, 2-magnetic conduction base, 3-magnetic conduction plate, 4-excitation coil, 5-magnetic conduction column, 6-light through hole, 7-excitation coil power supply unit, 8-objective lens, 9-light beam, 10-other optical module, 11-disassembly connection port, 12-sample, 13-sample stage.

The specific implementation mode is as follows:

the invention will be described in detail with reference to the accompanying drawings and specific embodiments. A magnetic field generating apparatus for a magneto-optical kerr measuring instrument, as shown in fig. 1, comprising: the magnetic pole comprises at least one magnetic pole 1, a magnetic conduction plate 3, at least one magnetic conduction column 5, a magnetic conduction base 2, an excitation coil 4 and an excitation coil power supply unit 7;

one end of the magnetic pole 1 is fixed on the magnetic conduction base 2, the magnetic conduction plate 3 is arranged above the other end of the magnetic pole 1, one end of the magnetic conduction column 5 is fixed with the magnetic conduction base 2, the other end of the magnetic conduction column is fixed with the magnetic conduction plate 3, the excitation coil 4 is wound on the surface of the magnetic pole 1, and the excitation coil power supply unit 7 is connected with the excitation coil 4 and supplies current to the excitation coil 4;

the magnetic conduction plate 3 is provided with a light through hole 6. The sample 12 is aligned below the light through hole 6, the sample table 13 is arranged below the sample, the sample table 13 is fixed on the magnetic conductive base, and the material of the sample table is insulating material, as shown in fig. 4, which is only one possibility, if the magnetic conductive base is designed differently, the sample table 13 can also be fixed on the test bed below the magnetic conductive base, and the magnetic conductive base is also placed on the test bed;

the magnetic pole 1 and the magnetic conduction plate 3 form a magnetic conduction path through the magnetic conduction base 2 and the magnetic conduction column 5.

The magnetic conducting columns 5 can be replaced by magnetic conducting walls, which are cylindrical magnetic walls surrounding the poles.

The magnetic pole 1, the magnetic conduction plate 3, the magnetic conduction column 5 and the magnetic conduction base 2 are integrally processed, or the magnetic pole 1, the magnetic conduction plate 3, the magnetic conduction column 5 and the magnetic conduction base 2 are spliced and processed;

a dismounting structure is arranged at the joint of the magnetic conduction column 5 or the magnetic conduction column 5 and the magnetic conduction plate 3, so that the magnetic conduction plate can be dismounted from the magnetic conduction column, as shown in fig. 2, a dismounting joint 11 is dismounted.

The magnetic poles, the magnetic conduction plates, the magnetic conduction bases and the magnetic conduction columns are made of ferromagnetic or ferrimagnetic substances.

The thickness of the magnetic conduction plate 3 is between 1mm and 10 cm.

The outer surface of the magnetic conduction column 5 or the magnetic conduction wall is wound by the excitation coil, and the excitation coil power supply unit supplies current to the excitation coil.

If the magnetic field generating device is used with an imaging system with an objective lens 8, the thickness of the magnetic conductive plate 3 at the position corresponding to the magnetic pole 1 cannot exceed the focal length of the objective lens 8, wherein the objective lens 8 is placed above the light-passing hole 6 of the magnetic field generating device.

The magnetic pole 1 is columnar.

The magnetic pole 1 is columnar, and the material of the magnetic pole is ferromagnetic or ferrimagnetic substance, including but not limited to metal, alloy or compound containing iron, cobalt and nickel; the thickness of the magnetic conduction plate 3 is between 1mm and 10cm, the shape is arbitrary, as shown in fig. 3, the shape is one possible case, a light through hole 6 is left on the area of the magnetic conduction plate 3 opposite to the pole face of the magnetic pole 1, and the material of the magnetic conduction plate 3 is magnetic metal, alloy or compound; the magnetic pole 1 and the magnetic conduction plate 3 are connected through the magnetic conduction base 2, the magnetic conduction column 5 and other structures to form a magnetic conduction path, so that the loss of magnetic potential is reduced, wherein the magnetic conduction base 2 and the magnetic conduction column 5 are made of ferromagnetic or ferrimagnetic substances, including but not limited to metals, alloys or compounds containing iron, cobalt and nickel; wherein the number of the magnetic conduction columns 5 is more than or equal to 1.

FIG. 3 is a top view of a magnetic field generating device for a magneto-optical Kerr measuring instrument according to an embodiment of the present invention; fig. 3 is a possible structure, in which only 4 magnetic conductive columns are shown, in practice, N magnetic conductive columns may be designed, N is greater than or equal to 1, and the shape of the magnetic conductive base is different according to the design of the magnetic conductive columns, as long as the magnetic pole 1, the magnetic conductive base 2, the magnetic conductive columns 5, and the magnetic conductive plate 3 are communicated to form a magnetic path.

An excitation coil 4 is wound around the magnetic pole 1. The magnetic pole 5 can be wound with the magnet exciting coil 4 or not.

It should be noted that the magnetic pole 1, the magnetic base 2, the magnetic column 5 and the magnetic plate 3 may be made of the same or different materials, and may be formed by splicing or integrally processing, and all of them are within the protection scope of the present invention.

The magnet exciting coil 4 is formed by winding a metal conductor, wherein at least 1 magnet exciting coil 4 is arranged outside the magnetic pole 1; the magnetic pole 5 may be surrounded by the excitation coil 4, or not with the excitation coil 4. The shape of the magnetic conducting pole 5 is not limited. Fig. 2 shows a possible example of the connection between the magnetic conductive plate 3 and the magnetic conductive pole 5. The main component of the field coil power supply unit is a dc or ac power supply in order to supply current to the field coil 4.

In addition, a detachable structure 11 may be disposed at the magnetic conduction column 5 or at the joint of the magnetic conduction column 5 and the magnetic conduction plate 3, as shown in fig. 2, so that the magnetic conduction plate 3 can be conveniently removed. Under the configuration, the sample 12 is arranged near the magnetic pole 1, and the device can still apply a magnetic field to the sample 12, so that the device has the advantages that the blocking of the magnetic conduction plate 3 is avoided, and the test light path module can be infinitely close to the sample; the disadvantage is that the magnetic field amplitude is reduced compared to the configuration with the magnetically permeable plate 3.

The magnetic pole 1, the magnetic conduction base 2, the magnetic conduction column 5, the magnetic conduction plate 3 and other components are communicated to form a magnetic path. When the magnetic field generating device works, the exciting coil power supply unit 7 applies current to the exciting coil 4, after the exciting coil 4 generates a magnetic field, magnetic flux is formed in a magnetic path formed by the magnetic pole 1, the magnetic conducting plate 3, the magnetic conducting column 5 and the magnetic conducting plate 3 which are communicated, and a strong magnetic field is generated near the position of a space where the magnetic pole 1 and the magnetic conducting plate 3 are opposite, namely a sample 12 shown in fig. 4. An optical module is arranged near the magnet, the detection light beam 9 can enter the sample 12 through the light through hole 6, and the reflected light returns to the optical detection module through the light through hole 6, so that the invention can support the optical test on the sample under high magnetic field. It should be noted that the thickness of the magnetic conductive plate 3 can be designed as required, for example, if the present magnet is used with an imaging system (i.e. other optical module 10 than the objective lens) with an objective lens 8, the thickness of the magnetic conductive plate 3 at the position corresponding to the magnetic pole 1 should not exceed the focal length of the objective lens 8, so that the sample 12 can be placed at the focal point of the objective lens imaging. The light emitted by the objective lens can penetrate through the through hole 6, and the light reflected by the sample returns to the objective lens through the through hole 6, so that imaging and optical testing are completed.

While the best mode for carrying out the invention has been described in detail and illustrated in the accompanying drawings, it is to be understood that the foregoing description is only illustrative of the presently preferred embodiments of the invention and that no limitation on the scope of the invention is thereby intended, such an improvement or modification being obvious to one skilled in the art.