Giant Enhancement of Surface Second Harmonic Generation in BaTiO_3 due to Photorefractive Surface Wave Excitation

摘要

We report observation of strongly enhanced surface SHG in BaTiO_3 due toexcitation of a photorefractive surface electromagnetic wave. Surface SHintensity may reach 10^{-2} of the incident fundamental light intensity.Angular, crystal orientation and polarization dependencies of this SHG arepresented. Possible applications of this effect in nonlinear surfacespectroscopy are discussed.