Uniform bi-planar coil design considering coupling effect of finite thickness for SERF magnetometer array calibration inside magnetically shielded room

Abstract

A novel uniform bi-planar coil (UBC) design method for atomic magnetometer array calibration inside a magnetically shielded room (MSR) with finite thickness is proposed, by which the accuracy of computational model could enhances up to approximately an order of magnitude. Firstly, to solve the coupling effect of the magnetic shield thickness on magnetic field, an improved image method and target field method (TFM) is proposed to obtain a highly accurate model of the UBC magnetic field under the square ferromagnetic boundary, in which a multiple reflection model is introduced based on the image method and TFM. Secondly, the coil parameters are optimized by successive iterations, which effectively avoids the degradation of the magnetic field uniformity caused by the magnetically shielded layer. Simulation and experimental results demonstrate the effectiveness of the proposed method, which can effectively guide the design of UBCs for atomic magnetometer calibration.