Planar Coil Design for Nuclear Magnetic Resonance Gyroscope Using Genetic Algorithm

In this article, we present a design for planar coils used in nuclear magnetic resonance gyroscope (NMRG) using genetic algorithm (GA), aiming to provide a highly uniform bias field in target regions. By optimizing current loops with proper distributions, our planar coils offer superior magnetic field uniformity compared to Helmholtz coils, while maintaining a similar conversion coefficient. Additionally, we analyze the errors caused by wire routing and thermal effects on the uniformity and conversion coefficient. The results indicate that the planar coils demonstrate significant robustness against routing errors and thermal expansion by using low thermal expansion material due to heating in the NMRG setup. We also fabricate a prototype and test its performance in the actual experimental system and it shows great performance. The proposed planar coil design provides a compact, efficient, and robust solution for generating uniform magnetic fields in NMRG, mitigating magnetic field gradient-induced relaxations, and enhancing the performance of this quantum device.