IEEE Transactions on Instrumentation and Measurement

In Situ Suppression of Thermal–Magnetic Coupling Noise in Atomic Sensors

Yijin Liu, Bin Wang, Di Gong, Weiyi Wang, Dinghui Gong, Xiaofei Huang, Kai Wei

Published Jan 1, 2026• 0 citations

Abstract

Spin-based sensors, such as magnetometers and comagnetometers, require precise control of thermal conditions and magnetic fields to achieve optimal performance. Thermal-magnetic coupling noise, induced by heating systems, is one of the limiting factors for sensitivity improvement. In this paper, the in-situ suppression method is proposed to eliminate thermal-magnetic coupling noise by employing the double-layer heater with dynamically adjustable current ratios. The in-situ method is verified across two distinct systems, including commercial magnetometer and the self-developed comagnetometer. For magnetometer system, the heating-induced magnetic interferences of the double-layer heater along three directions have been decreased over 2 orders compared to a conventional heater. Similarly, the total magnetic flux density has been suppressed by more than 78%. Furthermore, the thermal-magnetic coupling noise in K-Rb-21Ne comagnetometer equipped with the double-layer heater is in-situ suppressed to 6.54×10-9°/s/Hz1/2(0.01 fT/ Hz1/2) at 1 Hz, achieving a noise reduction of 22 dB compared to ex-situ method and 24 dB suppression relative to a conventional heater. Besides, the double-layer heater ensures a uniform and stable thermal field across the vapor cell, with a temperature variance less than 0.65 °C and a temperature fluctuation 65% lower than a conventional heater. This work advances ultra-sensitive quantum sensors by providing an effective method to in-situ suppress thermal-magnetic coupling noise.

DOI: 10.1109/tim.2026.3677970

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