Development of helium-free torque magnetometer

无氦扭矩磁力计的研制

• 批准号: 12554012
• 负责人: ISHIDA Takekazu
• 金额: $ 8.51万
• 依托单位: Osaka Prefecture University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12554012/
• 关键词: Variable field magnet; Torque magnetometer; 4K refregerator; Maget stage; 1.5 K sample space; Piezo torque sensor; 10000 Gauss; LabVIEW; ピエゾ抵抗トルクセンサー

We have developed a new torque magnetometer on the basis of a 4-K refrigerator. The system temperature can be lowered down to 1.5 K by pumping liquefied helium from a top loading sample space. A piezoresisitor bridge on a cantilever is used to detect torque acting on a sample. A transverse magnetic field is supplied by a variable field permanent magnet up to 10 KG. We find that a sensitivity of our torque magnetometer is 10^<-10> Nm. Our cryostat consists of a 4-K refrigerator (Sumitomo Heavy Industries, Ltd.) and an exchange gas cooling system (Janis). The top-loading sample space is inserted into a bore of a permanent magnet (magnetic Solutions MM-1000-48), which produces a transverse magnetic field. The magnet consists of the two concentric dipole-ring magnets. The inner magnet as well as the outer magnet can be rotated independently by stepper motors and positioning systems. Thus, the magnetic field as a vector sum can be altered from 0 to 10 kG at any orientation angle. A torque sensor attached to a copper sample holder is a microfabricated Si substrate cantilever based on a bridge circuit. This consists of the four-constantan piezoresistors (Quantum Design). The off balance signal of the bridge is quickly measured by a direct trigger link between an anovoltmeter (Keithley 2182) and a current source (Keithley 2400). A torque chip is 25 μm in thickness, a sample stage is 2 X 2mm, and an arm is A mm in length. Torsion of the cantilever yields a change in piezoresistors. The torque sensor can be rotated by using a stepper motor (Oriental Motor) equipped at the top of the insert cryost at. Angular resolution of the motor is 0.0036 degrees. A sample temperature can be controlled by a temperature controller (Lakeshore 340). The system is totally controlled by a LabVIEW program.

我们在4K制冷机的基础上研制了一种新的扭矩磁强计。通过从顶部加载的样品空间泵入液氦，系统温度可以降低到1.5K。悬臂上的压阻电桥用来检测作用在样品上的扭矩。横向磁场由高达10千克的可变场永磁体提供。我们发现，我们的扭矩磁强计的灵敏度为10^&lt；-10；Nm。我们的低温恒温器由一台4-K冰箱(住友重工业株式会社)组成。和交换气体冷却系统(JANIS)。将顶部加载的样品空间插入永磁体(Magic Solutions MM-1000-48)的孔中，从而产生横向磁场。该磁体由两个同心偶极环磁体组成。内磁体和外磁体均可通过步进电机和定位系统独立旋转。因此，磁场作为矢量和可以在任何方位角上从0到10千克变化。安装在铜样架上的扭矩传感器是一种基于电桥电路的微制造硅衬底悬臂梁。这包括四常数压敏电阻(量子设计)。电桥的不平衡信号通过阳极表(Keithley 2182)和电流源(Keithley 2400)之间的直接触发链路快速测量。扭矩芯片厚度为25μm，样品台为2×2 mm，臂长为A mm。悬臂梁的扭转导致压敏电阻的变化。扭矩传感器可以通过安装在镶件顶部的步进电机(东方电机)来旋转。该马达的角分辨率为0.0036度。样品温度可由温度控制器(湖岸340)控制。该系统完全由LabVIEW程序控制。

项目成果

T. Ishida, K. Kitamura, K. Okuda, and H. Asaoka: "Intgrinsic Pinning does not Influence the Vortex Melting Transition of YBa2Cu3O6.94 in H perpendicular c Configuration"J. Phys. Soc. Jpn.. 70. 2110-2113 (2001)

T. Ishida、K. Kitamura、K. Okuda 和 H. Asaoka：“内在钉扎不会影响 H 垂直 c 构型中 YBa2Cu3O6.94 的涡旋熔化转变”J。

N.Yamamoto et al.: "Superconducting Anisotropy in Nd_{1.85} Ce_{0.15}CuO_{4} Single Crystals"Physica C. 357・360. 298-301 (2001)

N. Yamamoto 等：“Nd_{1.85} Ce_{0.15}CuO_{4} 单晶中的超导各向异性”Physica C. 357・360 (2001)。

S. Nakata, M. Yoshida and T. Ishida: "Vortex Behavior of 1.8-μm Triangular Microhole Lattice on Pb Film : Matching Effect"Physica C. 378-381. 560-563 (2002)

S. Nakata、M. Yoshida 和 T. Ishida：“Pb 薄膜上 1.8 μm 三角形微孔晶格的涡流行为：匹配效应”Physica C. 378-381 (2002)。

石田武和 他: "JAERL Review"日本原子力研究所. 7 (2002)

Takekazu Ishida 等：“JAERL Review”日本原子能研究所 7 (2002)。

T.Ishida et al.: "Direct Observation of Vortex Images on Lead Micro-Hole Lattice by SQUID Microscope"Physica C. (2001)

T.Ishida 等人：“通过 SQUID 显微镜直接观察铅微孔晶格上的涡旋图像”Physica C. (2001)