A widely tunable laser frequency offset lock with digital counting.

Area of Science:

• Atomic, Molecular, and Optical Physics
• Laser Spectroscopy
• Quantum Optics

Background:

• Precise control of laser frequencies is essential for advanced experiments like laser cooling and trapping.
• Existing methods for stabilizing radio frequency (RF) offsets between lasers can be limited in tuning range and agility.
• Dynamically tunable RF offsets are needed to rapidly scan laser frequencies over broad ranges.

Purpose of the Study:

• To demonstrate a novel hybrid analog+digital electronic lock for stabilizing dynamically tunable RF offsets between two lasers.
• To provide a robust method for referencing multiple slave lasers to a single master laser with high precision and tunability.
• To enable rapid and accurate frequency tuning of lasers for applications in laser cooling and trapping.

Main Methods:

• Development of a hybrid analog and digital electronic lock system.
• Implementation of a feedback loop to stabilize the RF offset between two lasers.
• Characterization of the system's capture range, tuning range, and frequency agility.

Main Results:

• Achieved an 80 MHz capture range and a +/-7 GHz tuning range.
• Demonstrated a frequency agility of 1 MHz/micros.
• Observed low (<30 ppm) drift in the absolute optical frequency difference after 1000 seconds.

Conclusions:

• The hybrid electronic lock effectively stabilizes dynamically tunable RF offsets between lasers.
• The system's wide tuning range and high agility are suitable for laser cooling and trapping applications.
• This technique facilitates referencing multiple slave lasers to a master laser with enhanced flexibility and precision.