低温环境下霍尔探头标定  

Calibration of Hall probes at cryogenic temperature

作　　者：张伟[1] 王淑华[1] 张继东[1] 钟逸[1] 刘以勇[1] 何永周[1] 王莉[1] 周巧根[1] 

机构地区：[1]中国科学院上海应用物理研究所张江园区,上海201204

出　　处：《核技术》2014年第1期1-5,共5页Nuclear Techniques

基　　金：国家自然科学基金资助项目(11175238)资助

摘　　要：利用高精度低温霍尔探头可以测量永磁体在低温环境下的磁性能,如何对高精度霍尔探头在低温环境下进行精确标定对于永磁体低温磁性能研究有着重要意义。上海光源磁测实验室在霍尔探头常温标定的基础上,利用小型制冷机把霍尔探头置于液氮温区,通过在制冷机冷头上安装精确控制的电加热器可调节测试温度(6.5-300 K),并实现恒温。初步标定实验结果表明,低温霍尔探头灵敏度随着温度的下降逐渐上升,在50 K以下趋于平缓,相比常温灵敏度增大约4%。标定后的该探头可以测量低温环境下永磁体的磁性能,并可满足永磁体在低温环境下的性能研究需求。Background： The performance of permanent magnets at cryogenic temperature can be measured by using high-precision halt sensors. Purpose： Accurate calibration of high-precision hall sensor at cryogenic temperature is of great significance for the research on magnetic properties of cryogenic magnet. Methods： In Shanghai Synchrotron Radiation Facility （SSRF）, we had the hall sensor placed at the helium temperature by using a cryo cooler based on the success of hall sensor calibration at room temperature. Several electric heaters mounted at the cold head are used to precisely adjust the test temperature （from 6.5 K to 300 K） and keep the temperature constant. The sensitivity of the Hall probes was measured at temperature range from 6.5 K to 300 K over a magnetic field range of＋l.8 T. Results： It was found that the sensitivity increased as the temperature decreased from 300 K to about 150 K and became flattened below 50 K. The increase was 4% or so compared with the normal temperature sensitivity. Conclusion： The calibrated probe can be used to measure the performance of permanent magnet and meet the demand of permanent magnet property under low temperature environment.

关 键 词：上海光源 低温波荡器 霍尔探头 低温标定 

分 类 号：TL503.8[核科学技术—核技术及应用]