High-power dual-comb thin-disk laser oscillator for fast high-resolution spectroscopy

Area of Science:

• Laser Physics
• Spectroscopy
• Optical Engineering

Background:

• Free-running dual-comb systems offer next-generation technology potential.
• Dual-comb thin-disk lasers (TDLs) provide high average power for spectroscopy.
• TDL noise, often from cooling, challenges spectroscopic applications.

Purpose of the Study:

• Confirm the suitability of dual-comb TDLs for high-resolution spectroscopy.
• Investigate and characterize noise in a novel dual-comb TDL system.
• Demonstrate the system's capability for rapid spectral detection.

Main Methods:

• Developed a dual-comb TDL oscillator using intra-cavity polarization splitting.
• Generated two asynchronous pulse trains (240-fs duration, 6-W/8-W average power, ~97-MHz repetition rate).
• Conducted detailed noise analysis, identifying repetition frequency as the dominant correlated noise source (~85%).

Main Results:

• Achieved dual asynchronous pulse trains from a single laser cavity.
• Demonstrated significant correlation in frequency noise between the two pulse trains.
• Successfully detected acetylene absorption spectrum in 1 millisecond using free-running operation.

Conclusions:

• Dual-comb TDLs, utilizing polarization splitting, are suitable for high-resolution spectroscopy.
• Identified and quantified correlated noise, crucial for spectroscopic accuracy.
• This work is a key step towards practical mid-infrared dual-comb spectroscopy systems.