A high-performance frequency stability compact CPT clock based on a Cs-Ne microcell.

Area of Science:

• Atomic, Molecular, and Optical Physics
• Metrology and Measurement Science
• Microfabrication and MEMS Technology

Background:

• Development of compact and stable atomic clocks is crucial for navigation, communication, and fundamental science.
• Coherent Population Trapping (CPT) offers a promising approach for miniaturized atomic clocks using alkali vapors.
• Microfabricated vapor cells are key components for realizing chip-scale atomic clock (CSAC) devices.

Discussion:

• A table-top cesium (Cs) clock utilizing coherent population trapping (CPT) in a microfabricated Cs-Ne buffer gas cell demonstrates exceptional frequency stability.
• Optimization of the CPT signal contrast at 80°C cancels temperature-dependent frequency shifts, enhancing clock performance.
• Active stabilization techniques are employed to maintain clock operation at a zero-light-shift point, minimizing external influences.

Key Insights:

• Maximized CPT signal contrast achieved at 80°C, coinciding with the cancellation of Cs clock frequency's temperature dependence.
• Demonstrated frequency stability of 3.8 × 10⁻¹¹ at 1 second, improving to below 10⁻¹¹ for durations up to 50,000 seconds.
• Successful integration of a single buffer gas (Ne) in a microfabricated cell for high-performance atomic clock applications.

Outlook:

• This work validates the potential of single buffer gas vapor cells for next-generation chip-scale atomic clocks.
• Further research can explore alternative buffer gases and cell designs to enhance stability and reduce size.
• The developed technology could lead to widespread adoption of high-precision timing in portable and embedded systems.