Single-modulator, dual comb serrodyne spectroscopy

Area of Science:

• Physics
• Spectroscopy
• Optical Engineering

Background:

• Dual optical frequency comb spectroscopy offers high-speed, broadband measurements without mechanical components.
• Existing methods may involve complex hardware setups or limitations in sideband separation.

Purpose of the Study:

• To present a simplified dual optical frequency comb spectroscopy system using differential chirp downconversion and serrodyne modulation.
• To demonstrate the system's capability in measuring sharp cavity resonances and methane transitions.

Main Methods:

• Combining differential chirp downconversion for broad spectral probing.
• Utilizing serrodyne modulation within a single modulator to separate positive and negative sidebands.
• Applying the technique to measure cavity resonance and near-infrared methane transitions.

Main Results:

• Successful measurement of a sharp cavity resonance, showcasing system performance.
• Acquisition of near-infrared methane spectra, validated against spectroscopic databases.
• Demonstration of high mutual coherence between optical combs due to method simplicity.

Conclusions:

• The serrodyne modulation approach offers reduced hardware requirements and enhanced simplicity for dual comb spectroscopy.
• The technique is suitable for precise spectral measurements and shows potential for photonic integration.
• This method advances high-speed, broadband spectroscopic analysis capabilities.