22 November 2013 Azimuthal polarization for Raman enhancement in capillary waveguides
Author Affiliations +
Optical Engineering, 52(11), 117103 (2013). doi:10.1117/1.OE.52.11.117103
Hollow, metal-lined capillary waveguides have recently been utilized in spontaneous gas-Raman spectroscopy to improve signal strength and response time. The hollow waveguide is used to contain the sample gases, efficiently propagate a pump beam, and efficiently collect Raman scattering from those gases. Transmission losses in the waveguide may be reduced by using an azimuthally polarized pump beam instead of a linearly or radially polarized pump. This will lead to improved Raman signal strength, accuracy, and response time in waveguide-based Raman gas-composition sensors. A linearly polarized laser beam is azimuthally polarized using passive components including a spiral phase plate and an azimuthal-type linear analyzer element. Half-wave plates are then used to switch between the azimuthally polarized beam and the radially polarized beam with no change in input pump power. The collected Raman signal strength and laser throughput are improved when the azimuthally polarized pump is used. Optimization of the hollow waveguide Raman gas sensor is discussed with respect to incident pump polarization.
© 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)
Jessica C. Mullen, Michael P. Buric, Benjamin T. Chorpening, Steven D. Woodruff, "Azimuthal polarization for Raman enhancement in capillary waveguides," Optical Engineering 52(11), 117103 (22 November 2013). https://doi.org/10.1117/1.OE.52.11.117103


Design of an 1800nm Raman amplifier
Proceedings of SPIE (October 11 2013)
Bending effects on IR hollow waveguides
Proceedings of SPIE (January 19 2001)
Photonic waveguiding structures with loss and gain
Proceedings of SPIE (May 04 2011)
Beam profile analysis of waveguide-delivered IR lasers
Proceedings of SPIE (April 21 1999)
Spectroscopy gas sensing based on hollow fibres
Proceedings of SPIE (May 06 2011)

Back to Top