Stability of a frequency-comb-based transfer-lock using a passive Fabry-Perot resonator

Area of Science:

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

Background:

• Precise laser frequency control is crucial for advanced spectroscopic techniques.
• Existing methods often face limitations in wavelength range or complexity.
• Stabilizing lasers to passive resonators can be affected by environmental drifts.

Purpose of the Study:

• To develop a robust laser frequency stabilization method using a frequency comb and GPS reference.
• To enable transfer locking of lasers beyond the direct frequency comb range.
• To improve the stability and applicability of laser systems for precision measurements.

Main Methods:

• Utilizing a frequency comb (FC) and a GPS-referenced radio frequency counter for laser stabilization.
• Implementing optical serrodyning for a wide laser tuning range.
• Employing an efficient scheme to suppress residual amplitude modulation in Pound-Drever-Hall locking.

Main Results:

• Achieved absolute frequency stability better than 2×10^-13 for timescales up to 300 s.
• Demonstrated transfer locking of lasers at wavelengths outside the FC's usable range.
• Successfully suppressed residual amplitude modulation, enhancing lock stability.

Conclusions:

• The developed transfer-lock technique offers a versatile and stable solution for laser frequency control.
• This method significantly enhances the feasibility of applications requiring precise laser frequencies, such as coherent Raman spectroscopy.
• The technique is particularly beneficial for the production of ultracold dipolar heteronuclear molecules.