Vector magnetometer based on the effect of coherent population trapping.

Area of Science:

• Atomic physics
• Geophysics
• Sensor technology

Background:

• Coherent population trapping (CPT) atomic clocks offer high precision timing.
• Magnetometers are crucial for measuring magnetic fields in various scientific and technological fields.
• Existing vector magnetometers can be complex or lack sensitivity.

Purpose of the Study:

• To present a method for converting a CPT atomic clock into a CPT vector magnetometer.
• To achieve sensitive, direction-aware magnetic field measurements without mechanical components.
• To demonstrate a cost-effective add-on for existing atomic clock systems.

Main Methods:

• Utilizing a coherent population trapping (CPT) atomic clock as the base system.
• Implementing a simple add-on module to enable vector magnetic field detection.
• Employing a 3D Helmholtz coil system for external magnetic field compensation.

Main Results:

• Successfully converted a CPT atomic clock into a CPT vector magnetometer.
• Achieved magnetic field strength and direction measurement sensitivity of sub-nT/√Hz within a 10-Hz bandwidth.
• Demonstrated an angular resolution of approximately 10⁻² degrees.

Conclusions:

• The developed method provides a novel, low-cost approach to vector magnetometry.
• This technique allows for precise magnetic field sensing without mechanical parts, enhancing robustness.
• The CPT vector magnetometer has potential applications in navigation, geophysics, and fundamental physics research.