Symmetry Analysis of ZnSe(100)/Air Interface By Second Harmonic Generation

We measured the polarized and azimuthal dependencies of optical second harmonics generation (SHG) on polished surfaces of ZnSe(100) single crystal surface in air, using a fundamental wavelength of 1.06μm. By considering both, the bulkand surfaceoptical nonlinearities within the electric dipole approximation, we analysed the data for all four combination of pand s-polarized incidence and output. The measurement using Sin − Sout is thereby particularly useful in the determining of the symmetry ZnSe(100)/contamination layer-interface, which would lower the effective symmetry of ZnSe(100) from C4v to C2v. The analysis of p-incident and p-output configuration allows us to distinguish the [011]and [011]directions.