Resonant effects in optical second-harmonic generation from alkali coveredV. G. Bordo1, G. Marowsky2, J. Zhang3 and H.-G. Rubahn4
1 Natural Sciences Center, A. M. Prokhorov General Physics Institute Russian Academy of Sciences - 119991 Moscow, Russia
2 Laser Laboratorium Göttingen e.V. - Hans-Adolf-Krebs-Weg 1 D-37077 Göttingen, Germany
3 Optical Engineering Department, Xian Institute of Technology - Xian, PRC
4 Fysisk Institut, Syddansk Universitet - DK-5230 Odense M, Denmark
received 26 May 2004; accepted in final form 26 October 2004
published online 8 December 2004
Polarized second-harmonic generation (SHG) coverage dependencies for alkali ( ) adsorption on both at room and at low temperatures are obtained for fundamental wavelengths of 497 , 570 and 1067 , showing characteristic and reproducible non-monotonic changes of SHG efficiency. At submonolayer coverage the SHG intensities are qualitatively different for visible vs. near-resonant IR radiation. In the coverage regime , low-symmetry - bonds, resulting from a -induced surface reconstruction, are formed, which are resonant with 1067 radiation. By comparing parallelly and perpendicularly polarized coverage dependencies, we deduce that the resonant contribution in the parallel configuration is due to the -component.
42.65.-k - Nonlinear optics.
78.20.-e - Optical properties of bulk materials and thin films.
78.66.-w - Optical properties of specific thin films.
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