Accurate frequency referencing for fieldable dual-comb spectroscopy

Abstract

A fieldable dual-comb spectrometer is described based on a "bootstrapped" frequency referencing scheme in which short-term optical phase coherence between combs is attained by referencing each to a free-running diode laser, whilst high frequency resolution and long-term accuracy is derived from a stable quartz oscillator. This fieldable dual-comb spectrometer was used to measure spectra with full comb-tooth resolution spanning from 140 THz (2.14 um, 4670 cm^-1) to 184 THz (1.63 um, 6140 cm^-1) in the near infrared with a frequency sampling of 200 MHz (0.0067 cm^-1), ~ 120 kHz frequency resolution, and ~ 1 MHz frequency accuracy. High resolution spectra of water and carbon dioxide transitions at 1.77 um, 1.96 um and 2.06 um show that the molecular transmission acquired with this fieldable system did not deviate from those measured with a laboratory-based system (referenced to a maser and cavity-stabilized laser) to within 5.6x10^-4. Additionally, the fieldable system optimized for carbon dioxide quantification at 1.60 um, demonstrated a sensitivity of 2.8 ppm-km at 1 s integration time, improving to 0.10 ppm-km at 13 minutes of integration time.

References in corpus (10)

• Adaptive real-time dual-comb spectroscopy
• Frequency-agile dual-comb spectroscopy
• Coherent Dual Comb Spectroscopy at High Signal to Noise
• Picometer-resolution dual-comb spectroscopy with a free-running fibre laser
• Operation of an optically coherent frequency comb outside the metrology lab
• A bidirectional dual-comb ring laser for simple and robust dual-comb spectroscopy
• Ultra-broadband dual-comb spectroscopy across 1.0-1.9 μm
• High accuracy CO${}_2$ line intensities determined from theory and experiment
• Adaptive dual-comb spectroscopy in the green region
• Adaptive sampling dual terahertz comb spectroscopy using free-running dual femtosecond lasers

Cited by in corpus (9)

• High Coherence Mid-Infrared Dual Comb Spectroscopy Spanning 2.6 to 5.2 microns
• Self-corrected chip-based dual-comb spectrometer
• Broadband Dual Frequency Comb Spectroscopy in a Rapid Compression Machine
• Tunable dual-comb from an all-polarization-maintaining single-cavity dual-color Yb:fiber laser
• 11-μs Time-resolved, Continuous Dual-Comb Spectroscopy with Spectrally Filtered Mode-locked Frequency Combs
• Spatially resolved mass flux measurements with dual comb spectroscopy
• Dual-comb spectroscopy with tailored spectral broadening in Si${}_3$N${}_4$ nanophotonics
• Demonstration of a uniform, high-pressure, high-temperature gas cell with a dual frequency comb absorption spectrometer
• Streaming Self-Corrected Dual-Comb Spectrometer