A multi-dimensional vector field magnet structure

Abstract

The present invention relates to a multi-dimensional vector magnet structure, which comprises a first coil, a second coil and / or a third coil; the first coil adopts one or more layers of CCT dipole coils, and the single-layer CCT coil generates a vector magnetic field having both X-direction and Z-direction components in the magnet aperture region; the second coil adopts one or more layers of CCT dipole coils, and the single-layer CCT coil generates a vector magnetic field having both Y-direction and Z-direction components in the magnet aperture region; the third coil adopts one or more conventional coils, and a single conventional coil generates a vector magnetic field distributed along the Z axis in the magnet aperture region; wherein the Z axis is assumed to be the central axis direction of the CCT dipole coil, and the X axis and the Y axis are the pole head directions corresponding to the CCT of the first coil and the second coil, respectively.

Description

Technical Field

[0001] The present invention relates to a novel superconducting magnet structure, in particular to a multi-dimensional vector field magnet structure based on canted-cosin-theta (CCT for short). Background Art

[0002] Vector magnets have important applications in scientific research. The use of magnetic field technology can effectively promote the development of physics, biology, materials and other disciplines, and vector magnets can provide good experimental conditions for them. The use of two-dimensional or three-dimensional vector magnets can be used for positioning research, which provides the possibility for more complex experiments, such as studying the anisotropy of materials, the Hall effect, the single electron tunneling effect, etc. For experimental research that requires a magnetic field in any direction in space, there are two ways to implement it: fixed magnetic field direction + sample rotation, fixed sample + magnetic field direction rotation. Vector field magnets are a type of magnet that can generate a rotating magnetic field. There is no need for a mechanical structure to rotate the sample, but to adjust the magnetic field size and the angle relative to the sample, which greatly simplifies the complexity of the vector field application platform and facilitates commercial promotion.

[0003] Vector field magnets achieve the rotation of magnetic field direction by controlling current rather than mechanical operation, which provides many possibilities for experiments. Vector field magnets generate magnetic field components in any direction at any position and plane in space. The coil structure used by vector field magnets on the market is as follows: Figure 1 , Figure 2 As shown, common ones include solenoid coils, racetrack coils or saddle coils, etc. The advantages are simple structure and mature technology, but the disadvantages are large magnet volume, small good field range and poor accuracy. Due to the limitations of the above coil characteristics, the magnet size is too large for large-sized samples. Summary of the invention

[0004] In view of the above problems, the object of the present invention is to provide a multi-dimensional vector field magnet structure with compact structure, large good field range and high uniformity.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is: a multi-dimensional vector field magnet structure, the structure comprising a first coil, a second coil and / or a third coil;

[0006] The first coil uses one or more layers of CCT two-pole coils, and the single-layer CCT coil generates a vector magnetic field having both X-direction and Z-direction components in the magnet aperture area;

[0007] The second coil uses one or more layers of CCT two-pole coils, and the single-layer CCT coil generates a vector magnetic field with both Y-direction and Z-direction components in the magnet aperture area;

[0008] The third coil adopts one or more conventional coils, and a single conventional coil generates a vector magnetic field distributed along the Z axis in the magnet aperture area;

[0009] The Z axis is the central axis direction of the CCT dipole coil, and the X axis and the Y axis are the pole head directions corresponding to the CCT dipole coils of the first coil and the second coil respectively.

[0010] Furthermore, the assembly order of the first coil, the second coil and / or the third coil is arbitrary, that is, the combination of the three coils generates the required spatial vector magnetic field in the magnet aperture area; in addition, any two combinations of the first coil, the second coil and the third coil generate a two-dimensional vector magnetic field in the magnet aperture area.

[0011] Furthermore, when the multi-layer CCT coils are connected in series and the multi-layer CCT coils have an even number of layers:

[0012] The inclination angle is alternating, and only an enhanced dipole vector magnetic field distributed along the X-axis or Y-axis direction is generated in the magnet aperture area;

[0013] The inclination angle is in the same direction, and an enhanced CCT vector magnetic field is generated in the magnet aperture area with a preset angle direction to the central axis;

[0014] Furthermore, the multi-layer CCT coils are connected in series, and the multi-layer CCT coils have an odd number of layers:

[0015] The tilt angles are alternated, and a vector magnetic field having both an X-axis or Y-axis component and a Z-axis component and having a direction different from that of Bcct is generated in the magnet aperture region, where Bcct is the vector magnetic field generated by a single-layer CCT;

[0016] The inclination angles are in the same direction, and an enhanced CCT vector magnetic field is generated in the magnet aperture area with a preset angle to the central axis.

[0017] Furthermore, the third coil is a solenoid coil, a racetrack coil or a saddle coil.

[0018] Furthermore, the single-layer CCT coil structure includes a series of periodically continuously distributed single-turn inclined spiral coils, the inclined spiral coils are solidified on the cylindrical frame to form an inclined solenoid magnet structure, and the multiple layers of inclined solenoid coils are connected in series with each other.

[0019] Furthermore, the parameter equation of the CCT single-layer coil is:

[0020]

[0021] Among them, R refers to the radius of the coil, θ refers to the azimuth angle in the circumferential direction, w refers to the turn spacing, and α refers to the inclination angle of the coil to the midplane.

[0022] Furthermore, the first coil, the second coil and / or the third coil are all made of superconducting cables.

[0023] The present invention adopts the above technical solution, which has the following advantages:

[0024] 1. The present invention can use CCT coils and / or conventional coil structures to form a vector field magnet. The Z component of the cross-sectional current density in the overlapped section of the CCT coil approximately satisfies the Cosine Theta distribution, and can generate a high-quality dipole field in the aperture area. It has the characteristics of compact structure, large good field area, high resolution, etc., and the cylindrical structure is easy to integrate;

[0025] 2. The CCT magnet coil structure of the present invention is novel and lightweight. The vector magnet structure adopts superconducting technology to achieve high magnetic field and three-dimensional full-space equal-mode magnetic field rotation, which is particularly suitable for scientific research fields requiring high-precision large-sample vector fields;

[0026] In summary, the CCT magnet structure of the present invention has excellent mechanical properties and is suitable for all low-field and high-field working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components. In the accompanying drawings:

[0028] Figure 1 A schematic diagram of an existing three-dimensional vector magnet based on a Helmholtz coil structure;

[0029] Figure 2 It is a dipole field magnet of an existing conventional coil structure, wherein (1) is a solenoid coil, (2) is a racetrack coil, and (3) is a saddle coil;

[0030] Figure 3 Schematic diagram of the CCT dipole coil structure of the first coil of this embodiment, wherein (1) a single-layer CCT coil (odd number) generates a vector magnetic field distributed along the X-axis and the Z-axis in the magnet aperture; (2) a double-layer CCT coil (even number with alternating inclination angles) generates a vector magnetic field distributed along the X-axis in the magnet aperture, and the vector magnetic field distributed along the Z-axis is offset;

[0031] Figure 4 Schematic diagram of the CCT dipole coil structure of the second coil of this embodiment, wherein (1) a single-layer CCT coil (odd number) generates a vector magnetic field distributed along the Y axis and the Z axis in the magnet aperture; (2) a double-layer CCT coil (even number with alternating inclination angles) generates a vector magnetic field distributed along the Y axis in the magnet aperture, and the vector magnetic field distributed along the Z axis is offset;

[0032] Figure 5 Schematic diagram of the synthesis of the vector magnetic field of the vector magnet composed of the first coil (single-layer CCT) and the third coil in the inner hole area of ​​this embodiment;

[0033] Figure 6 Schematic diagram of a three-dimensional vector field magnet structure based on a CCT coil structure of this embodiment, wherein (1) is a first coil, (2) is a second coil, and (3) is a third coil. The schematic diagram only takes a single-layer coil as an example. The order of the three groups of coils is arbitrary, and the number of layers of each group of coils is single or multi-layer. DETAILED DESCRIPTION

[0034] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0035] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise" and "have" are inclusive and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0036] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0037] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside", "outside", "below", "above", etc. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0038] In this embodiment, the XYZ coordinate system can adopt the Cartesian right-hand coordinate system or the Cartesian left-hand coordinate system. In this embodiment, the Cartesian right-hand coordinate system is used as an example. The Z axis is assumed to be the central axis direction of the CCT diode coil skeleton tube, which is usually also the direction in which the sample is placed along the length position. The direction of the CCT diode coil pole head is the Y axis, and the direction perpendicular to the Z axis on the plane of the CCT diode coil is the X axis. Of course, for the convenience of description, the X axis, Y axis and Z axis of this embodiment are only used as the distinguishing description of the three coordinate axes, and should not be limited by the above names in actual use. The names of each coordinate axis can be defined according to actual needs.

[0039] like Figures 3 to 5 As shown, the multi-dimensional vector magnet structure provided in this embodiment includes a first coil 1, a second coil 2 and / or a third coil 3;

[0040] like Figure 3 As shown, the first coil 1 adopts one or more layers of CCT dipole coils. The single-layer CCT dipole coil generates a vector magnetic field having both X-direction and Z-direction components in the magnet aperture region, and the multi-layer CCT dipole coil is used to increase the size of the required magnetic field component. When in use, the first coil 1 can be located at the innermost side of the multi-dimensional vector magnet structure to generate a Bcct vector magnetic field having an X-axis component. This is taken as an example and is not limited to this.

[0041] like Figure 4 As shown, the second coil 2 adopts one or more layers of CCT dipole coils. The single-layer CCT dipole coil generates a vector magnetic field having both Y-direction and Z-direction components in the magnet aperture region, and the multi-layer CCT dipole coil is used to increase the size of the required magnetic field component. When in use, the second coil 2 can be placed outside the first coil 1 to generate a Bcct vector magnetic field having a Y-axis component.

[0042] like Figure 6 As shown, the third coil 3 adopts one or more conventional coil structures. A single conventional coil generates a vector magnetic field distributed along the Z axis in the magnet aperture area. Multiple conventional coils are used to improve the magnitude and uniformity of the magnetic field. In this example, the Z axis is the central axis direction of the CCT coil skeleton. The first coil is Figure 3For example, the Y axis is the starting axis of the azimuth angle θ, the X axis is the direction perpendicular to the Y axis and the Z axis, and is also the direction where the pole head of the CCT two-pole magnet is located. Similarly, the second coil 2 is different in that the X axis is specified as the starting axis of the azimuth angle θ, that is, the Y axis is the direction where its pole head is located, which can also be regarded as being obtained by rotating the first coil along the Z axis by 90°.

[0043] The third coil 3 is used to generate a Bz vector magnetic field distributed along the Z-axis direction in the inner hole area of ​​the magnet.

[0044] In some embodiments of the present invention, the first coil 1, the second coil 2 and / or the third coil 3 are assembled in any order, that is, the three coils generate vector magnetic fields with components in the X-axis, Y-axis and Z-axis directions respectively, and the resultant components Bx, By and Bz in the three directions finally synthesize the required spatial vector magnetic field. For example, the third coil 3 can be set outside the first coil 1 and the second coil 2 in the spatial structure, such as Figure 5 As shown, the vector magnet composed of the first coil 1, the second coil 2 and the third coil 3 is a three-dimensional vector magnet, and the three coils are combined to generate the required spatial vector magnetic field in the magnet aperture area. Among them, the first coil 1, the second coil 2 and the third coil 3 can also be combined arbitrarily in pairs to generate a two-dimensional vector magnetic field in the magnet aperture area.

[0045] In some embodiments of the present invention, the first coil 1 is taken as an example for detailed description, and the second coil 2 is similar to the first coil 1 and will not be described in detail.

[0046] like Figure 3-4 As shown, the multi-layer CCT coil of the first coil 1 is an odd-numbered layer, and the vector magnetic field generated by the odd-numbered layer CCT coil with alternating inclination angles or the same inclination angles in the magnet aperture area is shown in Table 1;

[0047] When the multi-layer CCT coil of the first coil 1 is an even number of layers, the vector magnetic field generated by the even number of layers of CCT coils with alternating inclination angles or the same inclination angles in the magnet aperture area is as shown in Table 1:

[0048] Table 1

[0049] CCT Coil Inclination angle Alternating inclination angle Even-numbered layers <![CDATA[Enhanced Bx + Enhanced Bz (i.e., Enhanced B cct )]]> Enhanced Bx (Bz almost completely cancels out) Odd-numbered layers <![CDATA[Enhanced Bx + Enhanced Bz (i.e., Enhanced B cct )]]> Enhanced version of Bx+Bz (n-1 layers of Bz are all offset)

[0050] Note: Bx(Bz) is the X(Z) direction component of the vector magnetic field Bcct generated by a single-layer CCT. The enhanced version means that n layers of CCT each generate corresponding Bcct, and the components of Bcct corresponding to each layer: the resultant components with the same direction are approximately equal to n times Bx(Bz) in value, which can be regarded as the functional enhancement of the corresponding field components of the single-layer CCT coil; the resultant components with opposite directions will cancel each other out in value, with the effect that only the uncancelled partial field components remain in the inner hole area.

[0051] like Figure 5As shown, the enhanced Bcct is oriented at a preset angle to the central axis, so when combined with other coil types it can produce a shaped vector magnet suitable for special physical requirements.

[0052] In some embodiments of the present invention, the third coil 3 is a solenoid coil, a racetrack coil or a saddle coil.

[0053] In some embodiments of the present invention, the CCT dipole single-layer coil structure includes a series of periodically distributed single-turn inclined spiral coils, the inclined spiral coils are solidified on a cylindrical frame to form an inclined solenoid magnet structure, and the multiple layers of inclined solenoid coils are connected in series with each other. The space trajectory of the inclined solenoid winding is determined by a set of parameter equations. The parameter equation of the CCT single-layer coil is:

[0054]

[0055] Among them, R is the radius of the coil, θ is the azimuth angle in the circumferential direction, w is the turn spacing, and α is the distance between the coil and the midplane (such as Figure 3 The tilt angle of the XZ plane in the image is different, and the CCT coils in different layers have different R.

[0056] In some embodiments of the present invention, the first coil 1, the second coil 2 and / or the third coil 3 are all made of superconducting cables. The superconducting cables may be NbTi or Nb3Sn, etc. This is taken as an example and is not limited thereto.

[0057] In some embodiments of the present invention, the first coil 1, the second coil 2 and the third coil 3 can be powered separately, and the user controls the power supply according to the manual data of the test calibration to obtain the vector magnetic field of the required size and direction, or obtains the required magnetic field through closed-loop control of the sensor.

[0058] In some embodiments of the present invention, the first coil 1, the second coil 2 and the third coil 3 can share the same supporting frame, or can be separated separately and finally assembled into a vector magnet. The specific structure of the supporting frame is not limited, and the corresponding structure can be adopted according to actual conditions.

[0059] The above embodiments are only used to illustrate the present invention, wherein the structure, connection mode and manufacturing process of each component may be changed. Any equivalent transformations and improvements based on the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A multi-dimensional vector field magnet structure, characterized in that: The structure includes a first coil, a second coil and a third coil; The first coil uses one or more layers of CCT two-pole coils, and the single-layer CCT coil generates a vector magnetic field having both X-direction and Z-direction components in the magnet aperture area; The second coil uses one or more layers of CCT two-pole coils, and the single-layer CCT coil generates a vector magnetic field with both Y-direction and Z-direction components in the magnet aperture area; The third coil adopts one or more conventional coils, and a single conventional coil generates a vector magnetic field distributed along the Z axis in the magnet aperture area; the third coil is a solenoid coil, a racetrack coil or a saddle coil; The Z axis is the central axis direction of the CCT dipole coil, and the X axis and the Y axis are the pole head directions corresponding to the CCT dipole coils of the first coil and the second coil, respectively.

2. The multi-dimensional vector field magnet structure according to claim 1, characterized in that: The first coil, the second coil and the third coil are assembled in any order, that is, the combination of the three coils generates the required spatial vector magnetic field in the magnet aperture area; in addition, any two combinations of the first coil, the second coil and the third coil generate a two-dimensional vector magnetic field in the magnet aperture area.

3. The multi-dimensional vector field magnet structure according to claim 1, characterized in that: When the multi-layer CCT coils are connected in series and the multi-layer CCT coils have an even number of layers: The inclination angle is alternating, and only an enhanced dipole vector magnetic field distributed along the X-axis or Y-axis is generated in the magnet aperture area; The inclination angles are in the same direction, and an enhanced CCT vector magnetic field is generated in the magnet aperture area with a preset angle to the central axis.

4. The multi-dimensional vector field magnet structure according to claim 1, characterized in that: The multi-layer CCT coils are connected in series, and the multi-layer CCT coils have an odd number of layers: The tilt angles are alternated, and a vector magnetic field having both an X-axis or Y-axis component and a Z-axis component and having a different direction from Bcct is generated in the magnet aperture region, where Bcct is the vector magnetic field generated by a single-layer CCT; The inclination angles are in the same direction, and an enhanced CCT vector magnetic field is generated in the magnet aperture area with a preset angle to the central axis.

5. The multi-dimensional vector field magnet structure according to any one of claims 1 to 4, characterized in that: The single-layer CCT coil structure includes a series of periodically continuously distributed single-turn inclined spiral coils, which are solidified on a cylindrical frame to form an inclined solenoid magnet structure, and the multiple layers of inclined solenoid coils are connected in series with each other.

6. The multi-dimensional vector field magnet structure according to claim 5, characterized in that: The parameter equation of the single-layer CCT coil is: in, R is the coil radius, θ is the azimuth in the circumferential direction, w is the turn spacing, α It refers to the inclination angle of the coil to the midplane.

7. The multi-dimensional vector field magnet structure according to any one of claims 1 to 4, characterized in that: The first coil, the second coil and the third coil are all made of superconducting cables.

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