Abstract
We have extended cavity ringdown spectroscopy from its conventional optical-absorption mode of operation into the regime of coherent Raman spectroscopy. Continuous-wave stimulated Raman gain spectra of the ν₁ rovibrational fundamental Raman band of methane gas at 2916.5-cm⁻¹ are measured, using tunable cw laser light at ~1544 nm to probe ringdown decay from a rapidly-swept optical cavity that is itself inside the cavity of a cw single-longitudinal-mode Nd:YAG ring laser operating at ~1064.5 nm. Recent progress on this project has substantially improved the previously reported noise-equivalent sensitivity, with a second ringdown cavity facilitating subtraction of troublesome infraredabsorption background signals. Moreover, by using a ringdown cavity in the form of a ring, the pump and ringdowndetected Stokes beams are able to co-propagate unidirectionally; this substantially reduces Doppler broadening.
| Original language | English |
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| Title of host publication | Proceedings of the 17th Australian Institute of Physics national congress 2006 |
| Editors | John Dobson, Robert Sang |
| Publisher | Australian Institute of Physics |
| Number of pages | 4 |
| ISBN (Print) | 0959806474 |
| Publication status | Published - 2006 |
| Event | Australian Institute of Physics National Congress (17th : 2006) - Brisbane Duration: 3 Dec 2006 → 8 Dec 2006 |
Conference
| Conference | Australian Institute of Physics National Congress (17th : 2006) |
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| City | Brisbane |
| Period | 3/12/06 → 8/12/06 |