Building a 'Zero-Magnetic' Space for SERF Atomic Magnetometers|SeeweTek | Magnetic Field Generators, Magnetic Testing Solutions, Physical Property Testing Solutions

Building a 'Zero-Magnetic' Space for SERF Atomic Magnetometers

Research on magnetocardiography and magnetoencephalography functional imaging at a quantum precision measurement laboratory in a top 985 university. The team independently developed a spin-exchange relaxation-free (SERF) atomic magnetometer with sensitivity reaching 10 fT/√Hz. However, geomagnetic field disturbances (~50 μT) and laboratory stray magnetic fields cause frequent depolarization of atomic spins, resulting in a signal loss rate of up to 40%, and weak magnetic anomaly signals are submerged in noise.

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Customer: Quantum Precision Measurement Laboratory of a top 985 university

Application Scenario: Research on magnetocardiography and magnetoencephalography functional imaging

The team independently developed a spin-exchange relaxation-free (SERF) atomic magnetometer with sensitivity reaching 10 fT/√Hz. However, geomagnetic field disturbances (~50 μT) and laboratory stray magnetic fields cause frequent depolarization of atomic spins, resulting in a signal loss rate of up to 40%, and weak magnetic anomaly signals are submerged in noise.

Solution:

We customized and delivered a magnetic shielding cylinder with shielding effectiveness >85 dB@1 Hz and residual internal magnetism <0.5 nT. Combined with active compensation coils, the environmental magnetic field was successfully suppressed to a fluctuation range of ±0.1 nT.

Results:

After deploying the shielding cylinder, the continuous locking time of the magnetometer increased from 2 hours to over 72 hours, and the signal-to-noise ratio improved by two orders of magnitude. The laboratory director stated: "The stable zero-magnetic environment finally allows us to unleash the full potential of the atomic magnetometer."