Laser with 10^-13 short-term instability for compact optically pumped cesium beam atomic clock

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Metrology and Standards

Background:

• High-performance atomic clocks are crucial for precise timekeeping and metrology.
• Compact atomic clocks are desirable for portable and diverse applications.
• Laser stabilization techniques are key to improving atomic clock accuracy.

Purpose of the Study:

• To develop a high-stability laser for a compact optically pumped cesium beam atomic clock.
• To evaluate the frequency instability of the stabilized laser.
• To assess the performance of the cesium atomic clock against a Hydrogen maser.

Main Methods:

• Modulation transfer spectroscopy was used to stabilize an 852 nm laser referenced on thermal cesium atoms.
• Optical heterodyne methods with two identical lasers evaluated laser frequency instability.
• Allan deviation was measured by comparing the cesium clock with a Hydrogen maser.

Main Results:

• The stabilized laser exhibited a frequency instability of 2.6×10^-13 at 5 s averaging time.
• The cesium beam atomic clock achieved an Allan deviation of 2×10^-12/τ, reaching 1×10^-14 within half a day.
• The clock's performance surpasses previously reported compact cesium beam atomic clocks at long averaging times.

Conclusions:

• A high-stability laser and a high-performance compact cesium beam atomic clock were successfully realized.
• The developed atomic clock offers superior Allan deviation compared to existing compact designs.
• The laser system holds potential as a compact optical frequency standard, advancing metrology and timekeeping.