Surface Dipole and Electric Quadrupole Contributions to the Anisotropic SecondHarmonic Generation from Noble Metal Surfaces

摘要

The azimuthal anisotropy in the optical second harmonic response from variouscrystal faces of Ag, Cu, and Au has been measured. Comparing the relative magnitudes of the isotropic and anisotropic signals indicates that the strong anisotropy observed from the (111) and (110) faces of noble metals can be assigned primarily to the dipolar surface response. This result contrasts to the case of Al single crystals where the anisotropy can be accounted for by the bulk quadrupole response.