Structure optimization of non-magnetic electric heating film for spin exchange relaxation free magnetometer

Spin exchange relaxation free (SERF) atomic magnetometer is one of the most sensitive magnetometers. High temperature and a non-magnetic environment are two key conditions to achieve ultra-high sensitivity. In this paper, a non-magnetic heating film with magnetic field self-suppression is optimized by the genetic algorithm method. Four structural parameters of the non-magnetic heating film including the wire spacing, wire width, wire thickness, and layer distance are optimized to minimize the magnetic field in the heated space. The simulation result based on the finite element analysis method shows that the magnetic field and the temperature field produced by a pair of heating films at the vapour cell are uniform. Finally, the magnetic field experiment proved that when the current is 10 ​mA, the magnetic field is 3.0520 ​nT. The temperature control experiment indicates that the temperature could be stabilized at 180 ​± ​0.2 ​°C. This study is significant for electric heating with a lower magnetic field and contributes to further improving the performance of atomic sensors.