2009/02/06 by Sanli Faez, P. M. Johnson, D. A. Mazurenko +1 · 1 citation
Physics and Astronomy · #physics.optics
paper · pdf · doi:10.1364/josab.26.000235
published as J. Opt. Soc. Am. B, vol. 26 no. 2, pp. 235-243 (2009) · 10 pages, 7 figures
arxiv created 2009/02/06 · arxiv updated 2009/12/01
We have experimentally measured the distribution of the second-harmonic intensity that is generated inside a highly-scattering slab of porous gallium phosphide. Two complementary techniques for determining the distribution are used. First, the spatial distribution of second-harmonic light intensity at the side of a cleaved slab has been recorded. Second, the total second-harmonic radiation at each side of the slab has been measured for several samples at various wavelengths. By combining these measurements with a diffusion model for second-harmonic generation that incorporates extrapolated boundary conditions, we present a consistent picture of the distribution of the second-harmonic intensity inside the slab. We find that the ratio ℓ2ω/Lc of the mean free path at the second-harmonic frequency to the coherence length, which was suggested by some earlier calculations, cannot describe the second-harmonic yield in our samples. For describing the total second-harmonic yield, our experiments show that the scattering parameter at the fundamental frequency \k1ωℓ1ω is the most relevant parameter in our type of samples.