A Novel Asymmetrical Heating Method for Improving the Temperature Spatial Homogeneity of Vapor Cell in Atomic Magnetometer

The atomic magnetometer in the application of simultaneous multichannel biomagnetic field measurement has gained increasing attention in recent researches. In this paper, a novel asymmetrical heating method for improving the temperature spatial homogeneity of the vapor cell in atomic magnetometer based on the finite element method was investigated. The homogeneity of temperature spatial distribution and the consistency of output signal from multilocation in a large vapor cell were numerically analyzed considering multichannel magnetic field measurement. With this asymmetrical heating method, the multilocation measurement signal regularity in the large vapor cell has been improved and the minimum variation coefficient of nine sensing areas' measurement signals decrease over 70% compared with the common heating method with the same heating temperature for the quadrate cell. This method is of great interest for the applications in miniaturing magnetometers of multichannel biomagnetic field measurement.