The optical second harmonic generation from a thin magnetic film on a nonmagnetic substrate is theoretically investigated for both sand p-polarized incident light. The contributions of lattice misfit strain as well as of misfit dislocation strain to the second-order nonlinear optical susceptibility are described using a nonlinear photoelastic tensor, together with the contribution of magnetizat...

This paper presents a theoretical model of nonlinear optical properties for strip plasmonic waveguides. The particular waveguides geometry that we investigate contains a gold core, adhesion layers, and silicon dioxide cladding. It is shown that the third-order susceptibility of the gold core significantly depends on the layer thickness and has the dominant contribution to the effective third-or...

We report the emission of strong coherent broadband terahertz radiation from 6H-silicon-carbide SiC excited with optical pulses. The measured terahertz spectral signal-to-noise ratio is better than one thousand. We determine that the terahertz radiation is generated via second order optical nonlinearity optical rectification . We present a measurement of the ratio of nonlinear susceptibility te...

The transient behavior of the optical susceptibility of polydiacetylene induced by an ultrafast pump field is investigated. Within a two-level model which includes phonon effects phenomenologically, an analytical expression for the nonlinear susceptibility is obtained. In addition to spectral hole burning, the novel phenomenon of optical nutation is found. Both this nutation and the shape of th...

A three-laboratory study was performed to evaluate conidium counting in a hematocytometer as a technique of inoculum preparation for susceptibility testing of Aspergillus spp. In addition, inocula were quantified by colony counting and optical density determination. The agreement and correlation coefficient between conidium and colony quantifications were 89.2% and 0.73 (P < 0.01). Correlations...

We investigate the nonlinear optical properties of graphene flakes using four-wave mixing. The corresponding third-order optical susceptibility is found to be remarkably large and only weakly dependent on the wavelength in the near-infrared frequency range. The magnitude of the response is in good agreement with our calculations based on the nonlinear quantum response theory.

Nonlinear optical (NLO) frequency conversion materials have a significant impact on laser technology, optical communication and optical storage technology. The search for new frequency conversion materials over the past decade has led to the discovery of many semi organic NLO materials with high nonlinear susceptibilities. Among the semi organic NLO materials metal complexes of the thiourea hav...