激光抽运-检测型原子磁力仪对交变磁场的测量

Measurement for alternating magnetic field by pump-probe atomic magnetometer based on laser

交变磁场作为磁场一种特殊的存在形式,有着广泛的应用和学术价值,而现阶段没有行之有效的方法对交变磁场进行绝对测量。抽运-检测型原子磁力仪具有量程宽、灵敏度高、能准确反映磁场真实特性,在磁场测量及标定中具有非常重要的意义。通过对抽运-检测型原子磁力仪在交变磁场激励下作用机理研究,对实验装置进行改进,实现抽运-检测型原子磁力仪对交变磁场的绝对测量,在Z轴方向上实现了背景磁场40000 nT,频率为100 Hz、磁场强度幅值为1000 nT的交变磁场测量;在Y轴方向上实现了背景磁场1000 nT,频率为20 Hz、磁场强度幅值为500 nT的交变磁场测量。测量结果表明该实验装置适用于低频、弱磁场强度交变磁场的测量,该方法为交变磁场的测量和标定提供一种切实可行的技术手段。

As a special form of magnetic field, alternating magnetic field has a wide range of applications and academic value. At present, there is no proven method for absolute measurement of alternating magnetic field. Pump detection atomic magnetometer has a wide range, high sensitivity and can accurately reflect the real characteristics of magnetic field, which is of great significance in magnetic field measurement and calibration. Through the research on the action mechanism of the pump detection atomic magnetometer excited by the alternating magnetic field, the absolute measurement of an alternating magnetic field by the pump detection atomic magnetometer is achieved through the improvement of the experimental. And the measurement of an alternating magnetic field with a background magnetic field of 40,000 nT,a frequency of 100 Hz and an amplitude of 1000 nT is achieved in the Z-axis direction;the measurement of alternating magnetic field in the Y-axis direction with a background field of 1000 nT,a frequency of 20 Hz and an amplitude of 500 nT. The results show that the experimental device is suitable for the measurement of alternating magnetic field at low frequencies and weak magnetic field strengths, and the method provides a practical technical tool for the measurement and calibration of alternating magnetic field.