调制磁场交流霍尔电压测量技术  

Measuring Hall effect with modulated magnetic field and AC sample current

作　　者：李潮锐 LI Chao-rui(School of Physics,Sun Yat-sen University,Guangzhou 510275,China;National Demonstration Center for Experimental Physics Education,Sun Yat-sen University,Guangzhou 510275,China)

机构地区：[1]中山大学物理学院,广东广州510275 [2]中山大学物理国家级实验教学示范中心,广东广州510275

出　　处：《物理实验》2021年第3期16-20,共5页Physics Experimentation

基　　金：中山大学物理学人才培养支撑条件建设项目(No.J1210034);中山大学本科教学质量工程项目(No.2018WL-ZLJG026,No.2019WL-ZLJG004)。

摘　　要：霍尔效应测量伴随着多种副效应,直流换向法在变温测量中存在难以克服的技术缺点.采用调制磁场与交流样品电流测量技术,并选择后者频率为前者的整数倍.当数据采样历遍调制磁场完整周期时,实验结果等效于磁场和样品电流换向测量.利用数字锁相放大器对被测信号谐波分量离散傅里叶分析原理,实现调制磁场交流霍尔电压实时测量.实验说明调制磁场交流霍尔测量技术方案的合理性,进而由变温霍尔测量结果表明该方法的科学性.The measurement on Hall effect is accompanied with some side effects,so that the DC reversing method is not suitable for variable temperature measurement.The measurement technology that combined with both modulated magnetic field and AC sample current was introduced,while the frequency of the latter was set to be the integral multiple of the former.When the whole period of modulated magnetic field was covered by the data sampling,the results were equivalent to the measurement of reversing both magnetic field and sample current.The harmonic component of the measured signal was analyzed with DFT using digital lock-in amplifier,which could be used to realize realtime measurement of AC Hall voltage with modulated magnetic field.The experiment illustrated that the new measurement technology was reasonable for Hall measurement of variable temperature.

关 键 词：霍尔效应 锁相技术 调制磁场 傅里叶分析 

分 类 号：O472.6[理学—半导体物理]