A compact micro-wave synthesizer for transportable cold-atom interferometers

Area of Science:

• Atomic physics
• Quantum sensing
• Metrology

Background:

• Atom interferometers are sensitive inertial sensors.
• Transportable inertial sensing requires compact and robust frequency sources.
• Stimulated Raman transitions are key for high-precision atom interferometry.

Purpose of the Study:

• To realize a compact microwave frequency synthesizer for atom interferometers.
• To enable transportable inertial sensing applications.
• To evaluate the performance of the synthesizer against state-of-the-art references.

Main Methods:

• Development of a compact microwave frequency synthesizer operating at 6.8 GHz for (87)Rb hyperfine transitions.
• Evaluation in time and frequency domains using LNE-SYRTE frequency references.
• Analysis of phase noise contributions and impact on atomic interferometer sensitivity.

Main Results:

• Achieved residual phase noise of -65 dB rad(2)/Hz at 10 Hz offset frequency.
• Measured white phase noise below -120 dB rad(2)/Hz for frequencies above 10 kHz.
• Demonstrated that phase noise contribution is well below the sensitivity limits of current cold atom inertial sensors.

Conclusions:

• The developed synthesizer offers significant improvements in size, simplicity, and power consumption.
• The device is suitable for field and mobile inertial sensing operations.
• Enables next-generation portable atomic sensors with enhanced performance.