Mid-infrared generation and spectroscopy with a PPLN ridge waveguide

Journal article

We have utilised a periodically poled LiNbO3 crystal with a waveguide structure to produce up to 146 μW of mid-IR radiation around 2976 cm-1 by difference frequency mixing of 1064 nm pump radiation with 1558 nm signal radiation. A conversion efficiency of 45%∈W-1 is achieved within a crystal of length 50 mm, and temperature tuning curves are reported. The resultant idler radiation is exploited for high resolution absorption studies of both methane and methanethiol. The absorption cross-sections for methanethiol in the region of 2979 cm-1 are measured and found to be ≈ 10-19 cm2, the relevance of these results to breath and headspace analysis of clinical samples containing volatile sulphur compounds is briefly discussed. © Springer-Verlag 2007.

Authors: Denzer, W; Hancock, G; Hutchinson, A; Munday, M; Peverall, R

• Publication status: Published
• Journal: APPLIED PHYSICS B-LASERS AND OPTICS
• Volume: 86
• Issue: 3
• Pages: 437-441
• Publication date: 2007-02-01
• DOI: 10.1007/s00340-006-2570-x
• EISSN: 1432-0649
• ISSN: 0946-2171
• Language: English