Multi-Parameter Optimization of Rubidium Laser Optically Pumped Magnetometers with Geomagnetic Field Intensity

Area of Science:

• Atomic physics
• Quantum sensing
• Magnetometry

Background:

• Optically pumped magnetometers (OPMs) utilize atomic properties for magnetic field measurement.
• High sensitivity in OPMs depends critically on the quality of the magnetic resonance signal.
• Rubidium-based OPMs are established magnetic sensors employing Zeeman effects and laser pumping.

Purpose of the Study:

• To optimize the experimental parameters of rubidium laser OPMs for enhanced magnetic resonance signal quality.
• To investigate the impact of various operational parameters on the magnetic resonance signal characteristics.
• To achieve improved sensitivity in rubidium laser OPMs operating in Earth's magnetic field.

Main Methods:

• Constructed an experimental system for rubidium laser OPMs centered around a rubidium atomic gas cell.
• Employed the linewidth and amplitude ratio (LAR) as the objective function for signal optimization.
• Systematically varied laser frequency, RF intensity, laser power, and cell temperature to measure magnetic resonance signals.

Main Results:

• Optimizing key parameters reduced the LAR of magnetic resonance signals by one order of magnitude.
• Demonstrated that optimal parameter combinations effectively enhance magnetometer sensitivity.
• Achieved a magnetic field sensitivity of 1.5 pT/Hz^1/2 @ 1 Hz under optimal conditions.

Conclusions:

• Parameter optimization is crucial for improving the performance of rubidium laser OPMs.
• The study provides a pathway to significantly enhance the sensitivity of these magnetic sensors.
• Findings offer valuable technical insights for the product development of rubidium laser OPMs.