Picture of wind turbine against blue sky

Open Access research with a real impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs.

The Energy Systems Research Unit (ESRU) within Strathclyde's Department of Mechanical and Aerospace Engineering is producing Open Access research that can help society deploy and optimise renewable energy systems, such as wind turbine technology.

Explore wind turbine research in Strathprints

Explore all of Strathclyde's Open Access research content

Coherent two-photon absorption spectroscopy of the Raman-active KGd(WO4)2 crystal

Major, Arkady and Aitchison, J.S. and Smith, Peter W.E. and Langford, Nigel and Ferguson, Allister I. (2004) Coherent two-photon absorption spectroscopy of the Raman-active KGd(WO4)2 crystal. Optics Letters, 29 (24). pp. 2896-2898. ISSN 0146-9592

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

We report on the systematic open-aperture Z-scan characterization of the two-photon absorption properties in one of the most efficient solid-state Raman frequency shifters, the crystal potassium gadolinium tungstate [KGd(WO4)2]. The two-photon absorption coefficient was determined in the 370-600-nm wavelength range, with the highest value found to be ~1.9 cm/GW at 370 nm. Nonlinear losses are crucial in determining the conversion efficiency of the stimulated Raman scattering process when it is excited with ultrashort laser pulses with photon energy exceeding half of the bandgap. In addition, the results were analyzed within the context of a simple two-parabolic-band theoretical model to yield an effective bandgap energy value for the crystal.