Human Magnetoencephalography Measurement by Highly Sensitive SERF Atomic Magnetometer

HUANG Shengjie1 ZHANG Guiying1 HU Zhenghui1 LIN Qiang1

(1.Collaborative Innovation Center for Bio-Med Physics Information Technology, College of Science, Zhejiang University of Technology, Hangzhou, Zhejiang, China 310023)

【Abstract】A highly sensitive noncryogenic rubidium magnetometer based on spin exchange relaxation free (SERF) is designed, whose sensitivity at 15 Hz isWith this SERF magnetometer, the difference in the human brain magnetic field induced by eye opening and closing is recorded inside the shielding barrel. This SERF magnetometer is operated in double light mode with a pump-probe arrangement. Compared with single beam arrangement, this SERF magnetometer can achieve a higher sensitivity and does not require any extra magnetic modulation. Thus, the complexity of the acquisition system is reduced and the lock-in amplifier is not needed any more. Moreover, this kind of configuration is easily adapted to miniaturize the sensor array for the future whole-head magnetoencephalography equipment.

【Keywords】 measurement; atomic magnetometer; spin exchange relaxation free; magnetoencephalography;


【Funds】 National Natural Science Foundation of China (61727821, 61475139) Young Scientists Fund of the National Natural Science Foundation of China (11704335)

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This Article


CN: 31-1339/TN

Vol 45, No. 12, Pages 192-196

December 2018


Article Outline


  • 1 Introduction
  • 2 Development of SERF atomic magnetometer
  • 3 Experimental results and analysis
  • 4 Conclusions
  • References