用于铯光泵磁强计的无磁恒温控制系统设计

Non-magnetic Thermostat Control System for Cesium Optical-pumping Magnetometer

针对铯光泵磁强计对原子气室温度高稳定性及无磁干扰的要求,设计了一种用于铯光泵磁强计的无磁恒温控制系统。该系统主要包括无磁加热器件与无磁恒温控制电路。无磁加热器件采用微机电系统工艺的双层对称四线结构,可有效抑制电流产生的磁场;无磁恒温控制电路通过交流加热进一步减小恒定磁场干扰,以现场可编程门阵列为核心,使用直接数字式频率合成技术产生高频加热信号,再经功率放大进行无磁恒温控制,减少硬件电路资源。测试结果表明,气室恒温控制的温度噪声峰峰值可达到0.02℃,满足光泵磁强计的性能要求。

Aiming at the requirement of high temperature stability and non-magnetic interference in the atomic gas cell of the cesium optical-pumping magnetometer, a non-magnetic thermostat control system for the cesium optical-pumping magnetometer is designed.The system mainly includes a non-magnetic heating chip and a non-magnetic thermostat control circuit.The non-magnetic heating chip adopts the double-layer symmetrical four-wire structure of MEMS technology, which can effectively suppress the magnetic field generated by the current;The non-magnetic thermostat control circuit uses AC heating to further reduce the constant magnetic field interference.With the field programmable gate array as the core, the direct digital frequency synthesis technology is used to generate high-frequency heating signals, and then the non-magnetic thermostat control is performed through power amplification to reduce the circuit hardware resource.The test results show that the temperature control stability of the gas cell can reach 0.02 ℃,which meets the performance requirements of the optical-pumping magnetometer.