C. Jordan et al., WAVELENGTH-DEPENDENT ANISOTROPY OF SURFACE 2ND-HARMONIC GENERATION FROM SI(111) IN THE VICINITY OF BULK ABSORPTION, Applied physics. B, Lasers and optics, 58(2), 1994, pp. 111-115
A wavelength-dependence study of surface second-harmonic generation fr
om Si(111) is presented. Femtosecond laser pulses tuned from 430 nm to
710 nm were used to probe the dispersion characteristics of the nonli
near response from the surface in the vicinity of bulk absorption. Cha
nges in the rotational symmetry and in the phase of the generated seco
nd-harmonic signal were observed. An explanation of the observed chang
es is given based on a simple anharmonic oscillator model [1].