Architecture for microcomb-based GHz-mid-infrared dual-comb spectroscopy
Abstract
Dual-comb spectroscopy (DCS) offers high sensitivity and wide spectral coverage without the need for bulky spectrometers or mechanical moving parts. And DCS in the mid-infrared (mid-IR) is of keen interest because of inherently strong molecular spectroscopic signatures in these bands. We report GHz-resolution mid-IR DCS of methane and ethane that is derived from counter-propagating (CP) soliton microcombs in combination with interleaved difference frequency generation. Because all four combs required to generate the two mid-IR combs rely upon stability derived from a single high-Q microcavity, the system architecture is both simplified and does not require external frequency locking. Methane and ethane spectra are measured over intervals as short as 0.5 ms, a time scale that can be further reduced using a different CP soliton arrangement. Also, tuning of spectral resolution on demand is demonstrated. Although at an early phase of development, the results are a step towards mid-IR gas sensors with chip-based architectures for chemical threat detection, breath analysis, combustion studies, and outdoor observation of trace gases.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 12, 2021
- Source ID
- 10.1038/s41467-021-26958-6
Entities
People
- Chengying Bao
- Heming Wang
- Kerry Vahala
- Lue Wu
- Myoung-Gyun Suh
- Qiang Lin
- Zhiquan Yuan
Organizations
- Air Force Research Laboratory Information Directorate
- Defense Threat Reduction Agency