Simultaneous laser frequency stabilization to an optical cavity and an iodine frequency reference.

Area of Science:

• Atomic, Molecular, and Optical Physics
• Laser Physics
• Metrology

Background:

• High-finesse optical cavities offer excellent short-term frequency stability.
• Molecular iodine frequency standards provide robust long-term frequency stability.
• Combining these systems presents a challenge in laser frequency control.

Purpose of the Study:

• To develop a hybrid laser system integrating molecular iodine and optical cavity frequency references.
• To leverage the distinct stability characteristics of both systems across different timescales.
• To achieve unprecedented laser frequency stability for precision applications.

Main Methods:

• Utilized frequency offset side-band locking technique.
• Employed an acousto-optical modulator driven ac-coupled servo-loop.
• Integrated molecular iodine and high-finesse optical cavity within a single laser system.

Main Results:

• Achieved cavity-limited stability of 10^-15 at 1 Hz.
• Demonstrated iodine-limited stability of 10^-13 below 10 mHz.
• Attained Allan deviation stability near 10^-15 at 1 s and 10^-14 for >100 s observation times.

Conclusions:

• The hybrid laser system successfully combines the long-term stability of iodine and short-term stability of optical cavities.
• This method offers a pathway to highly stable lasers for advanced metrology and fundamental science.
• The demonstrated stability levels are competitive with state-of-the-art frequency standards.