Abstract：The magnetic resonance signal characteristics of cesium-helium magnetometer (CHM) based on laser pumping was studied. By pumping cesium atoms with a narrow-line-width laser, the magnetometer achieved 12.3A/T current-magnetic field conversion efficiency, which is 13.5 times greater than the CHM based on the discharge lamp pumping. The “power broadening” was eliminated by indirect pumping. By analyzing the data and the theoretical value of the line width, it was concluded that the maximum broadening factor comes from the pulsed excitation. By measuring the background noise of the light source, magnetic field, photoelectric sensor and circuit, the largest noise source of the magnetometer was determined to be the light source and magnetic field, and the optimal light intensity was obtained by taking the magnetic field resolution as the optimization target. The magnetic field resolution of the cesium-helium magnetometer can reach 0.05nT.
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