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Title: Cavity-enhanced rotational Raman scattering in gases using a 20  mW near-infrared fiber laser

Authors:
; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1260291
Grant/Contract Number:
298 SC0010519
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Optics Letters
Additional Journal Information:
Journal Volume: 41; Journal Issue: 14; Related Information: CHORUS Timestamp: 2016-07-05 10:41:07; Journal ID: ISSN 0146-9592
Publisher:
Optical Society of America
Country of Publication:
United States
Language:
English

Citation Formats

Friss, Adam J., Limbach, Christopher M., and Yalin, Azer P.. Cavity-enhanced rotational Raman scattering in gases using a 20  mW near-infrared fiber laser. United States: N. p., 2016. Web. doi:10.1364/OL.41.003193.
Friss, Adam J., Limbach, Christopher M., & Yalin, Azer P.. Cavity-enhanced rotational Raman scattering in gases using a 20  mW near-infrared fiber laser. United States. doi:10.1364/OL.41.003193.
Friss, Adam J., Limbach, Christopher M., and Yalin, Azer P.. 2016. "Cavity-enhanced rotational Raman scattering in gases using a 20  mW near-infrared fiber laser". United States. doi:10.1364/OL.41.003193.
@article{osti_1260291,
title = {Cavity-enhanced rotational Raman scattering in gases using a 20  mW near-infrared fiber laser},
author = {Friss, Adam J. and Limbach, Christopher M. and Yalin, Azer P.},
abstractNote = {},
doi = {10.1364/OL.41.003193},
journal = {Optics Letters},
number = 14,
volume = 41,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1364/OL.41.003193

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  • Broadband and dual-broadband coherent anti-Stokes Raman scattering (CARS) are widely established tools for nonintrusive gas diagnostics. Up to now the investigations have been mainly performed for electronic nonresonant conditions of the gas species of interest. We report on the enhancement of the O2-N2 detection limit of dual-broadband pure rotational CARS by shifting the wavelength of the narrowband pump laser from the commonly used 532-266 nm. This enhancement is caused when the Schumann-Runge absorption band is approached near 176 nm. The principal concept of this experiment, i.e., covering the Raman resonance with a single- or dual-broadband combination of lasers in themore » visible range and moving only the narrowband probe laser near or directly into electronic resonant conditions in the UV range, should also be applicable to broadband CARS experiments to directly exploit electronic resonance effects for the purpose of single-shot concentration measurements of minority species. To quantify the enhancement in O2 sensitivity, comparative measurements at both a 266 and a 532 nm narrowband pump laser wavelength are presented, employing a 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyram (DCM) dye laser as a broadband laser source at 635 nm. An increase of approximately 13% in the ratio of the rotational CARS cross sections of O2 and N2 was obtained. The broad spectral width of the CARS excitation profile was approximately equal for both setups. Further enhancement should be achievable by shifting the narrowband pump laser closer toward 176 nm, for example, with a frequency-doubled optical parametric oscillator or an excimer laser. The principal concept of this experiment should also be applicable to broadband CARS experiments to directly exploit electronic resonance effects of the narrowband pump laser with electronic transitions of minority species for the purpose of single-shot concentration measurements of those species.« less
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  • We report that hyper-Rayleigh scattering, surface-enhanced hyper-Raman scattering, and two-photon excited luminescence occur intermittently by focusing a continuous-wave near-infrared (cw-NIR) laser into a colloidal silver solution including rhodamine 6G (R6G) and sodium chloride (NaCl). On the other hand, continuous hyper-Rayleigh scattering is observed from colloidal silver free from R6G and NaCl, demonstrating that hyper-Raman scattering and two-photon excited luminescence are attributed to R6G and their intermittent features are dependent on the colloidal dispersion. These results suggest that the cw-NIR laser has three roles; the source of the nonlinear response, optical trapping of nanoparticles, and making nanoparticle aggregates possessing the highmore » activity for the nonlinear response.« less
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