Experimental Exploration Of Miniature Magnetometer

With the demand of magnetic field measurement in modern society,all kinds of magnetometers have developed rapidly,among which atomic magnetometers stand out because of their advantages of easy miniaturization and high sensitivity.Atomic magnetometers used to be too large to be carried around and are not suitable for outdoor magnetic field measurement.From a practical point of view,atomic magnetometers need to be further reduced in size while maintaining high sensitivity.To this end,we did the following research:1.In the atomic magnetometer experiment,the volume of the laser and its frequency locking device is relatively large,so reducing the volume of relevant components of the light source is an important scheme for the miniaturization of the atomic magnetometer.So we built a small laser with a volume of only 2.9 cm×4.2 cm×4.2 cm using distributed Bragg reflection laser tube.The maximum optical power of the laser is 117 mW.The power drifts 0.6 % every 12 hours.Without external frequency locking,the wavelength of the output light field is shifted to 0.059 nm/? by temperature controller every 24 hours.2.The built small semiconductor laser was embedded into the atomic magnetometer system,and the influence of the laser's optical field noise and frequency bandwidth on the magnetic field sensitivity was analyzed.The experimental results show that the frequency jitter of the laser has little influence on the magnetometer sensitivity.And the magnetic field sensitivity of the atomic magnetometer is about 10 fT/(?),which meets the measurement requirements of the high sensitivity magnetometer.Our work explores the experimental miniaturization of atomic magnetometers and provides the possibility for the portability of atomic magnetometers.