A linewidth locking method to control the microwave power in optically pumped cesium-beam clocks.

Area of Science:

• Atomic Physics
• Metrology
• Frequency Standards

Background:

• Optically pumped cesium-beam frequency standards offer advantages over classical designs.
• Microwave power control is critical for Ramsey pattern linewidth and frequency stability.
• Traditional extremum methods for power control are suboptimal.

Purpose of the Study:

• To introduce and validate a novel linewidth locking method for microwave power control.
• To compare the performance of the new method against traditional techniques.
• To enhance the frequency stability of optically pumped cesium-beam clocks.

Main Methods:

• Analysis of optically pumped and classical cesium-beam tube responses to microwave power.
• Development of a linewidth locking method based on Ramsey pattern sensitivity.
• Experimental validation using an optically pumped cesium-beam frequency standard.

Main Results:

• The linewidth locking method effectively controls microwave power, leveraging the sensitivity of the Ramsey pattern linewidth.
• Experimental results show an Allan deviation of 2.64×10⁻¹²/τ for the optically pumped cesium-beam frequency standard.
• The new method achieved a 17% improvement in Allan deviation compared to the traditional extremum method.

Conclusions:

• The linewidth locking method provides a superior alternative for microwave power control in cesium frequency standards.
• Precise microwave power control leads to improved frequency stability and reduced Ramsey pattern linewidth.
• This advancement contributes to the development of more accurate and stable atomic clocks.