JP3039376B2 - SQUID magnetometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a SQUID magnetometer, and more particularly, to a SQUID (Superconducting Quantum Interference Device).
The present invention relates to a SQUID magnetometer that cools a pickup coil to a cryogenic state by a cryogenic refrigerator and guides an external magnetic flux detected by the pickup coil to the SQUID.

[0002]

2. Description of the Related Art Conventionally, a SQUI has been developed using a cryogenic refrigerator.
There has been proposed a SQUID magnetometer in which an ID and a pickup coil are cooled to a very low temperature state, and in this state, an external magnetic flux is detected by the pickup coil and led to a superconducting loop of the SQUID. Where SKU
It is preferable to use a dc-SQUID as the ID. In this case, the FLC circuit and the modulation coil are used to compensate for the fluctuation of the magnetic flux caused by guiding the magnetic flux detected by the pickup coil to the superconducting loop of the SQUID. That is common.

In such a SQUID magnetometer, the position of the pickup coil is preferably set as close as possible to a casing surrounding the cryogenic part. Therefore, of the plurality of cooling stages of the cryogenic refrigerator, for the final cooling stage, a fiber-reinforced plastic or the like reinforced by a cloth formed by knitting a wire made of a heat conductor into a cloth. Heat transfer support member 80
Are arranged in a thermally bonded state, and a pickup coil 83 is wound around a predetermined position of the electrothermal support member 80 (see FIGS. 9 and 10). FIG. 5 schematically shows a configuration of a conventional SQUID magnetometer.
A radiation shield 85 for shielding radiant heat is disposed inside a casing 84 that is evacuated to make the heat conduction in the internal space almost zero, and a final cooling stage (for example, approximately 4K) is surrounded by the radiation shield 85. (A stage for generating cold heat) is disposed. A SQUID 87 is arranged on the cooling stage 86 so as to be able to directly transfer heat, and is also provided with a SQUID 87 by a superconducting shield 87a.
The ID 87 is surrounded, and a heat transfer support member 89 is disposed via a heat transfer bracket 88. In FIG. 5, a heat transfer support member 89 extends upward through an upper portion of the radiation shield 85, and correspondingly, a casing 84
Has an upper portion locally extending upward.

By adopting the above configuration, even if the wire made of a heat conductor is made of metal, for example, Cu, if a wire coated with a resin is used, no current flows through this portion. Simply functioning as a heat conducting member, the pickup coil 83 can be cooled to an extremely low temperature, and the pickup coil 83 can be shifted to a superconductive state. Of course, SQUID 87 is also transited to the superconducting state,
It is possible to function as a QUID magnetometer. In addition, since the pickup coil 83 is located at the extension of the casing 84, the pickup coil 83 can be easily approached to a measurement target portion such as a human body, and the magnetic flux measurement of the measurement target portion can be performed with high sensitivity. High accuracy can be achieved.

[0005] Further, since a method of cooling these to a cryogenic state by heat transfer using a cryogenic refrigerator is employed instead of a method of immersing the SQUID and the pickup coil in liquid helium, the consumption of liquid helium is reduced. As a result, it is possible to prevent an increase in the operating cost, and a qualified person for the operation is not required.

[0006]

However, when performing biomagnetic measurement using the SQUID magnetometer having the above configuration, the number of SQUIDs and pickup coils (hereinafter, referred to as the number of channels) is generally used. It is necessary to increase the number of the coils and to bring each pickup coil as close as possible to the surface of the living body.

Since the surface of the living body is generally a curved surface, if the pickup coil 83 supported by the heat transfer supporting member 80 is to be arranged on the surface of the living body as described above, as shown in FIG. In addition, the base of the heat transfer support 80 must be arranged on a curved surface. As a result, the size of the final cooling stage must be increased, and at the same time, the size of the cryostat must be increased. As a result, the radiation penetration heat increases, and the cooling efficiency of the cryogenic refrigerator decreases. Therefore, a large-capacity cryogenic refrigerator must be employed, and the time required for cooling down from room temperature to cryogenic temperature becomes longer.

Further, the heat transfer support member is thermally contracted by being cooled to an extremely low temperature, and the pickup coil is separated from the casing, so that the magnetic flux detection sensitivity of the measurement target portion is reduced.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has an SQUID magnetometer capable of suppressing a decrease in cooling efficiency and a prolonged cooling down time. It is intended to provide.

[0010]

According to a first aspect of the present invention, there is provided a SQUID magnetometer having a SQUID magnetometer at a predetermined position of a cryogenic portion of a cryogenic refrigerator.
D is arranged so as to be able to conduct heat, and a pickup coil is supported so as to be able to conduct heat through a heat transfer support member to a predetermined position of the cryogenic part, and a part of the heat transfer support member retains its shape. The heat transfer support member is constituted by a member and a cloth-like body formed by knitting a wire made of a heat conductor, and the rest of the heat transfer support member is constituted by a cloth-like body formed by knitting a wire made of a heat conductor.

A SQUID magnetometer according to a second aspect of the present invention employs a SQUID magnetometer in which wires made of a heat conductor are arranged in parallel with each other in place of a cloth body formed by knitting wires made of a heat conductor. It is. 4. The SQUID magnetometer according to claim 3, wherein a part of the heat transfer supporting member is a tubular cloth body formed by knitting a wire made of a heat conductor, and an internal shape located on the inner surface side of the cloth body. A member composed of a holding member and an external shape holding member located on the outer surface side of the cloth body is employed, and the external shape holding member is made of a material having higher thermal conductivity than the internal shape holding member. The thing is adopted.

The SQUID magnetometer according to claim 4 employs a glass fiber reinforced plastic as the internal shape holding member, and employs an alumina ceramic as the external shape holding member. The SQUI of claim 5
D magnetometer, as a part of the heat transfer support member, a tubular cloth-like body formed by knitting a wire made of a heat conductor, an internal shape holding member located on the inner surface side of the cloth-like body, An external shape holding member which is located on the outer surface side of the cloth-like body and is extended so as to protrude from an end of the cloth-like body. A member made of a material having a higher thermal conductivity than the internal shape holding member is employed.

In the SQUID magnetometer according to the present invention, a member made of glass fiber reinforced plastic is used as the internal shape holding member, and a member made of alumina nitride ceramic is used as the external shape holding member.

[0014]

According to the SQUID magnetometer of the first aspect, the SQUID is disposed at a predetermined position of the cryogenic portion of the cryogenic refrigerator so as to be able to conduct heat, and the heat transfer support is provided at a predetermined position of the cryogenic portion. Since the pickup coil is supported so as to be able to conduct heat through the member, the SQ is similar to the conventional SQUID magnetometer.
The UID and the pickup coil can be cooled to a very low temperature state. A part of the heat transfer support member is constituted by a shape maintaining member and a cloth body formed by knitting a wire made of a heat conductor, and the rest of the heat transfer support member is formed by knitting a wire made of a heat conductor. Since the heat transfer support member is made of a cloth-like body, the remaining portion of the heat transfer support member has flexibility, and the pickup coils are arranged so as to be substantially equidistant from each other with respect to the curved surface to be measured. Even in this case, the base of the heat transfer supporting member can be arranged on a plane. Therefore, it is possible to prevent the cryogenic part from becoming larger than the cryogenic part due to the increase in the number of channels, and to prevent the required cool-down time from becoming unnecessarily long. be able to. In addition, it is possible to prevent the cryostat from becoming unnecessarily large, and to prevent the cooling efficiency from being unnecessarily reduced.

According to the SQUID magnetometer of the second aspect, instead of a cloth-like body formed by knitting wires made of a heat conductor, a wire made of a heat conductor is arranged in parallel with each other. As a result, the flexibility of the remaining portion of the heat transfer supporting member can be further increased, and the same operation as that of claim 1 can be achieved. According to the SQUID magnetometer of claim 3, as a part of the heat transfer support member, a tubular cloth body formed by knitting a wire made of a heat conductor and an inner surface side of the cloth body are located. A material comprising an internal shape holding member and an external shape holding member located on the outer surface side of the cloth-like body, and having a higher thermal conductivity than the internal shape holding member as the external shape holding member The distance between the pick-up coil provided on the outer surface of the external shape holding member and the tubular cloth is increased, and the thermal noise generated by the tubular cloth increases the pick-up coil. The influence on the SQUID magnetometer via the SQUID magnetometer can be suppressed.

In the case of the SQUID magnetometer according to the present invention, since the inner shape holding member is made of glass fiber reinforced plastic and the outer shape holding member is made of alumina ceramic, the pickup coil is used. The manufacturing accuracy of the groove for mounting can be increased. According to the SQUID magnetometer of claim 5, as a part of the heat transfer supporting member, a tubular cloth body formed by knitting a wire made of a heat conductor and an inner surface side of the cloth body are located. An internal shape holding member and an external shape holding member that is located on the outer surface side of the cloth body and is extended so as to protrude from an end of the cloth body are adopted, In addition, since the outer shape holding member is made of a material having a higher thermal conductivity than the inner shape holding member, the outer shape holding member is formed by a pickup coil provided on the outer surface of the outer shape holding member and the tubular cloth. Make the distance even bigger,
The influence of thermal noise generated by the tubular cloth on the SQUID magnetometer via the pickup coil can be further suppressed.

In the case of the SQUID magnetometer of claim 6, since the inner shape holding member is made of glass fiber reinforced plastic and the outer shape holding member is made of alumina nitride ceramics, the pickup is used. The manufacturing accuracy of the groove for mounting the coil can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the accompanying drawings showing embodiments. FIG. 1 is a schematic diagram showing one embodiment of the SQUID magnetometer of the present invention. This SQUID magnetometer has a radiation shield 2 for eliminating the influence of radiant heat inside a casing 1 in which the inside is evacuated to make the heat conduction almost zero. Has the last cooling stage 3 of the cryogenic refrigerator. A plurality of SQUIDs 4 are provided at predetermined positions of the cooling stage 3 so as to be able to transfer heat, and a heat transfer supporting member 5 is provided corresponding to each SQUID 4. Further, a pickup coil 6 is provided at the tip of each heat transfer support member 5. However,
In FIG. 1, for simplicity, one SQUID4
And only one heat transfer support member 5 is shown.

The heat transfer supporting member 5 penetrates a predetermined position of the radiation shield 2 and moves away from the cooling stage 3 (FIG. 1).
And a predetermined position of the casing 1 also corresponds to the heat transfer support member 5 so that the cooling stage 3
Extending away from the However, the length and direction of the local extension of the casing 3 are set so as to follow the curved surface of the measurement target portion.

FIG. 2 is a front view showing one embodiment of the heat transfer supporting member 5, and FIG. 3 is a side view. 2 and 3, a base member 3a integrally connected to a predetermined position of the last cooling stage 3 by screwing or the like is shown.
This functions as a part of the cooling stage 3 and constitutes a part of the cryogenic part described in the claims.
As shown in FIGS. 4 and 5, a superconducting shield 3b having an internal space 3c is provided at a predetermined position of the base member 3a, and the SQUID 4 accommodated in this space 3c is provided.
To prevent external noise magnetic flux from acting on. SQUID
Wirings for 4 and the like are drawn through holes 3d formed in the base member 3a and the superconducting shield 3b. Although two superconducting shields 3b are provided in FIG. 5, in order to correspond to FIGS. 2 and 3, one superconducting shield 3b may be removed. This heat transfer support member 5
There is a cloth body 5a integrally connected to the front end of the base member 3a by screwing or caulking, and a tubular body 5b integrally connected to the front end of the cloth 5a. The pickup coil 6 is provided at a predetermined position of the cylindrical body 5b. Also, as shown in FIG.
The two SQUIDs 4 and the two pickup coils 6 are brought to a very low temperature state by integrally connecting the two cloth-like bodies 5a to the one base member 3a and connecting the base member 3a to the final cooling stage 3. Can be cooled down.

The cloth-like body 5a is made of, for example, a non-magnetic metal such as copper or a carbon fiber, and is formed into a cloth by knitting a wire coated with a non-conductive material such as a resin vertically and horizontally. . Here, as each wire, one extending in the longitudinal direction of the cloth body 5a and one extending in a direction perpendicular to the longitudinal direction are used. Therefore, the oblique lines shown in FIGS. 2 and 3 do not indicate the direction of the wire. In addition, the cylindrical body 5
b is, for example, a non-magnetic metal such as copper or a carbon fiber, and is obtained by knitting a wire coated with a non-conductive material such as a resin vertically and horizontally into a cloth shape as a reinforcing fiber. It is a cylindrical body made of fiber reinforced plastic. In manufacturing the cloth body 5a and the cylindrical body 5b, a cloth body having a length corresponding to the sum of the entire lengths of the cloth body 5a and the cylindrical body 5b is created in advance. In addition, a method of integrating the synthetic resin into the cylindrical shape only at the portion to be formed as the cylindrical body 5b can be adopted. However, after integrating the synthetic resin into the entire length of the cloth-like body having the above-described length in a cylindrical shape, the synthetic resin may be removed only from the portion that should become the cloth-like body 5a. Of course, a cloth body may be provided so as to cover the outer peripheral surface of a cylindrical body made of a fiber reinforced resin reinforced with glass fiber or the like. The extent to which the distance between the measurement object and the pickup coil 6 increases can be suppressed. FIG. 7 shows a state in which a multi-channel SQUID magnetometer is manufactured using the SQUID magnetometer having the above configuration.

FIG. 7 shows a case where the surface to be measured is hemispherical. When the surface to be measured is hemispherical as described above, it is necessary that the distances from the respective surfaces to be measured of the plurality of pickup coils 6 are substantially equal to each other and that the pickup coils 6 are as close as possible to the surface to be measured. Therefore, each cylindrical body 5b is radially arranged with reference to the surface to be measured. In this case, the conventional S
If the heat transfer supporting member does not have flexibility over the entire range, as in the case of a QUID magnetometer, the distance between the bases of the heat transfer supporting members becomes extremely large, and inevitably the final cooling stage becomes large. In addition, the cryostat also becomes larger. However, in this embodiment, the tubular member 5b of the heat transfer support member 5 is not only flexible, and the cloth member 5a is flexible. The body 5a can be freely deformed, and as a result, the distance between the bases of the heat transfer support members 5 (the base of the cloth-like body 5a) can be reduced. Accordingly, the size of the final cooling stage 3 can be largely suppressed and the length of time required for cooling down can be significantly reduced, and the size of the cryostat can also be significantly reduced to reduce the cooling efficiency. It can be greatly suppressed.

SQUID 4 and pickup coil 6
Is cooled to a very low temperature (for example, 4K),
The magnetic flux can be measured with high sensitivity and high accuracy as with the conventional SQUID magnetometer. In order to keep the relative position of the distal end of the tubular body 5b with respect to the distal end of the extension of the casing 1 constant, for example, as shown in FIG. If a coil support base for directly fixing is provided, even if the heat transfer support member 5 contracts due to cooling to an extremely low temperature, the distal end of the tubular body 5b with respect to the distal end of the extension of the casing 1 can be used. The relative position can be kept constant, and higher sensitivity and higher precision magnetic flux measurement can be performed.

In the above description, the cloth-like body 5a made of a non-magnetic metal such as copper or a carbon fiber and knitted in a vertical and horizontal direction with a wire material coated with a non-conductor such as a resin has been described. Omit the wire extending in the direction perpendicular to the longitudinal direction of the, may be provided in parallel only the wire extending in the longitudinal direction,
In this case, the flexibility of the cloth body 5a can be increased.

FIG. 12 is an enlarged front view showing a main part of still another configuration example of the SQUID magnetometer of the present invention, FIG. 13 is a longitudinal sectional view at the center, and FIG. 14 is a plan view. In this SQUID magnetometer, the tip of the cloth body 5a is formed in a cylindrical shape, and an inner shape holding member 5b1 made of glass fiber reinforced plastic is provided on the inner surface side of the tubular portion, and alumina ceramics or the like is provided on the outer surface side. Shape holding member 5b2 made of a material having higher thermal conductivity than glass fiber reinforced plastic
Are provided, and the tubular portion of the cloth body 5a is sandwiched and integrated by the internal shape holding member 5b1 and the external shape holding member 5b2. A groove 5b3 for mounting the pickup coil 6 at a predetermined position on the outer surface of the external shape holding member 5b2.
Are formed. Here, the internal shape holding member 5b1 and the external shape holding member 5b2 correspond to the cylindrical body 5b.

When this configuration is adopted, since the thermal conductivity of the external shape holding member 5b2 is higher than the thermal conductivity of the internal shape holding member 5b1, both shape holding members 5b1
External shape holding members 5b for achieving the same pickup coil cooling effect as compared with the case where glass fiber reinforced plastic is used as 1, 5b2.
2 can be increased in thickness. As a result, the distance between the pickup coil and the cloth body 5a can be increased, and the influence of thermal noise generated by the cloth body 5a on the SQUID magnetometer via the pickup coil can be suppressed.

More specifically, when the outer shape holding member 5b2 is made of alumina ceramics, the thermal conductivity when copper is used as the wire contained in the cloth body 5a is about 450 W / (m · K), an internal shape maintaining member 5 made of glass fiber reinforced plastic
While the thermal conductivity of b1 is 0.7 to 0.9 W / (m · K), the thermal conductivity of the external shape holding member 5b2 is 2
0.9 W / (m · K). However, their thermal conductivity is at room temperature.

Here, the heat flow Q of a solid having a uniform cross section is expressed by Equation 1. Where A is the cross-sectional area of the solid (m ² ), T
1, T2 is the temperature (K) at both ends of a solid having a length L (m),
λ is the thermal conductivity {W / (m · K)}.

[0029]

(Equation 1) Since the thermal conductivity depends on the temperature, it cannot be calculated simply. However, assuming that the thermal conductivity of the above materials (glass fiber reinforced plastic and alumina ceramics) changes similarly with respect to temperature, the same temperature difference is allowed. Assuming the same amount of heat flows into each component, the tolerance for each thickness is the ratio of each thermal conductivity. In other words, in the case of a 0.1 mm thick part made of glass fiber reinforced plastic, if this is made of alumina ceramics, a 2.3 mm thick is allowed. Therefore, as described above, the pickup coil and the cloth body 5a
Can be increased, and the influence of thermal noise generated by the cloth-like body 5a on the SQUID magnetometer via the pickup coil can be suppressed.

When the external shape holding member 5b2 is made of alumina ceramics, it is possible to improve the manufacturing accuracy of the groove for mounting the pickup coil. FIG. 15 is an enlarged front view showing a main part of still another configuration example of the SQUID magnetometer of the present invention.
6 is a central longitudinal sectional view, and FIG. 17 is a plan view.

In this SQUID magnetometer, the tip of the cloth body 5a is formed in a cylindrical shape, and an inner shape holding member 5b1 'made of glass fiber reinforced plastic is provided on the inner surface side of the tip of the tubular portion. An external shape holding member 5b2 'made of a material having a significantly higher thermal conductivity than glass fiber reinforced plastic, such as alumina nitride ceramics (aluminum nitride / boronitride composite ceramics), on the outer surface side.
Are provided, and the tubular portion of the cloth body 5a is sandwiched and integrated by the internal shape holding member 5b1 'and the external shape holding member 5b2'. Then, only the external shape holding member 5b2 'is extended from the distal end of the tubular portion (external shape holding member 5b2').
2 'extends in a direction parallel to the central axis of the cylindrical portion), and a groove 5b3 for mounting the pickup coil 6 is formed at a predetermined position on the outer surface of the external shape holding member 5b2'. Here, the internal shape holding member 5b1 'and the external shape holding member 5b2' correspond to the cylindrical body 5b.

When this configuration is adopted, the thermal conductivity of the external shape holding member 5b2 'is reduced to the internal shape holding member 5b17.
Significantly higher than the thermal conductivity of the outer shape holding member 5b2 'compared to the case where both shape holding members 5b1' and 5b2 'are made of glass fiber reinforced plastic. The same degree of cooling effect of the pickup coil can be achieved only by providing the cloth-like body 5a partially without providing the body 5a. As a result, the distance between the pickup coil and the cloth body 5a can be significantly increased, and the influence of thermal noise generated by the cloth body 5a on the SQUID magnetometer via the pickup coil can be significantly suppressed.

When aluminum nitride / boroboronitride composite ceramics is employed, the thermal conductivity of the composite is 9%.
2.1 W / (m · K). Therefore, as in the case described above, in the case of a part allowed to have a thickness of 0.1 mm made of glass fiber reinforced plastic, when it is made of aluminum nitride / boro nitride composite ceramics, it is 10.2 mm.
Would be acceptable. In this configuration example, the external shape holding member 5b2 'can be extended by a length corresponding to the thickness of 10.2 mm. Therefore, the distance between the pickup coil and the cloth body 5a can be significantly increased, and the influence of the thermal noise generated by the cloth body 5a on the SQUID magnetometer via the pickup coil can be significantly suppressed.

When the outer shape holding member 5b2 'is made of alumina nitride ceramics, it is possible to improve the manufacturing accuracy of the groove for mounting the pickup coil.

[0035]

According to the first aspect of the present invention, since the remaining portion of the heat transfer supporting member has flexibility, the pickup coils are arranged so as to be substantially equidistant from the curved surface to be measured. Even so, the base of the heat transfer support member can be arranged on a flat surface, thereby preventing the cryogenic part from becoming larger than the cryogenic part due to the multi-channel structure. The cooling down time can be prevented from becoming unnecessarily long, and the cryostat can be prevented from becoming unnecessarily large, preventing the cooling efficiency from unnecessarily lowering. It has a specific effect that it can be performed.

According to the second aspect of the invention, the flexibility of the remaining portion of the heat transfer supporting member can be further enhanced, and the same effect as that of the first aspect can be obtained. According to a third aspect of the present invention, in addition to the effect of the first aspect, the distance between the pickup coil provided on the outer surface of the external shape holding member and the cylindrical cloth is increased, and the heat generated by the cylindrical cloth is increased. The noise is S through the pickup coil
This has a specific effect that the influence on the QUID magnetometer can be suppressed.

[0037] The invention of claim 4 has a unique effect that the manufacturing accuracy of the groove for mounting the pickup coil can be enhanced in addition to the effect of claim 3. According to the fifth aspect of the present invention, in addition to the effect of the first aspect, the distance between the pickup coil provided on the outer surface of the external shape holding member and the cylindrical cloth is further increased, and the cylindrical cloth is generated. There is a unique effect that the influence of thermal noise on the SQUID magnetometer via the pickup coil can be further suppressed.

The invention according to claim 6 has a unique effect that the manufacturing accuracy of the groove for mounting the pickup coil can be enhanced in addition to the effect of claim 5.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a SQUID magnetometer of the present invention.

FIG. 2 is a front view showing one embodiment of a heat transfer supporting member.

FIG. 3 is a side view of the same.

FIG. 4 is a front view showing a configuration of a base member.

FIG. 5 is a sectional view of the right half of the side surface of the base member, and an external view of the left half.

FIG. 6 is a side view showing a state in which two heat transfer support members are connected to one base member.

7 is a schematic diagram showing a state in which a multi-channel SQUID magnetometer is manufactured using the SQUID magnetometer having the configuration of FIG. 1;

FIG. 8 is a schematic diagram showing another configuration example of the SQUID magnetometer of the present invention.

FIG. 9 is a schematic diagram showing a configuration of a conventional SQUID magnetometer.

FIG. 10 is a perspective view schematically showing a configuration of a conventional heat transfer supporting member.

FIG. 11 is a schematic diagram showing a conventional SQUID magnetometer in a multi-channel configuration.

FIG. 12 is an enlarged front view showing a main part of still another configuration example of the SQUID magnetometer of the present invention.

FIG. 13 is a longitudinal sectional view at the center of the above.

FIG. 14 is a plan view of the same.

FIG. 15 is an enlarged front view showing a main part of still another configuration example of the SQUID magnetometer of the present invention.

FIG. 16 is a central vertical sectional view of the same.

FIG. 17 is a plan view of the same.

[Explanation of symbols]

 3 Final cooling stage 3a Base member 4 SQUID 5 Heat transfer support member 5a Cloth body 5b Cylindrical body 5b1, 5b1 'Internal shape holding member 5b2, 5b2' External shape holding member 6 Pickup coil

Claims (6)

(57) [Claims] The SQUID (4) and a pickup coil (6) are cooled to a cryogenic state by a cryogenic refrigerator, and an external magnetic flux detected by the pickup coil (6) is guided to the SQUID (4). In the magnetometer, the cryogenic portion of the cryogenic refrigerator (3) (3a)
The SQUID (4) is arranged at a predetermined position so as to be able to conduct heat, and the pickup coil is arranged so as to be able to conduct heat through a heat transfer support member (5) to a predetermined position of the cryogenic part (3) (3a). (6) is supported, and a part of the heat transfer support member (5) is constituted by a shape maintaining member (5b) and a cloth-like body (5a) formed by knitting a wire made of a heat conductor. The remaining part of the heat supporting member (5) is constituted by a cloth-like body (5a) formed by knitting a wire made of a heat conductor.
ID magnetometer. 2. The method according to claim 1, wherein wires made of a heat conductor are arranged in parallel with each other in place of the cloth body (5a) formed by knitting a wire made of a heat conductor. SQUID magnetometer. 3. A part of the heat transfer supporting member is located on the inner side of the tubular cloth body (5a) formed by knitting a wire made of a heat conductor. An internal shape holding member (5b1) and an external shape holding member (5b2) located on the outer surface side of the cloth body (5a), and the external shape holding member (5b2) is an internal shape holding member (5b1). 5b
The SQUID magnetometer according to claim 1, wherein the SQUID magnetometer is made of a material having a higher thermal conductivity than 1). 4. The SQUID magnetometer according to claim 3, wherein the inner shape holding member (5b1) is made of glass fiber reinforced plastic, and the outer shape holding member (5b2) is made of alumina ceramics. 5. A part of the heat transfer supporting member is located on the inner side of the tubular cloth body (5a) formed by knitting a wire made of a heat conductor. An internal shape holding member (5b1 '), and an external shape holding member located on the outer surface side of the cloth-like body (5a) and extending so as to protrude from an end of the cloth-like body (5a). (5b2 '), and the external shape holding member (5b2')
The SQUID according to claim 1, wherein the SQUID is made of a material having a higher thermal conductivity than the internal shape holding member (5b1 ').
Magnetometer. 6. The SQUID magnetometer according to claim 5, wherein the inner shape holding member (5b1) is made of glass fiber reinforced plastic, and the outer shape holding member (5b2) is made of alumina nitride ceramics.