The refractive-index nonlinearities of intersubband transitions in GaN/AlN quantum-well waveguides are investigated. A large spectral broadening of TM-polarized near-infrared pulses is observed after propagation through these devices due to intersubband self-phase modulation. From the measured data, a nonlinear refractive index n2 of 1.8 10 −12 cm2 /W is estimated at the operating wavelength of...

A theory for the nonlinear (with respect to the electric field) Faraday effect has been developed and applied to a simple model. Within the framework of this model, our analysis shows that the ratio of the nonlinear Uerdet constant to the linear Uerdet constant is proportional to the intensity of the incident light and depends on the frequency of light, the excitation energy of the model molecu...

We have recently developed a spectral re-shaping technique to simultaneously measure nonlinear refractive index and nonlinear absorption. In this technique, the information about the nonlinearities is encoded in the frequency domain, rather than in the spatial domain as in the conventional Z-scan method. Here we show that frequency encoding is much more robust with respect to scattering. We com...

In this study, refractive index changes associated with intersubband transitions in a spherical quantum dot, GaAs/AlxGa1−xAs, have been theoretically calculated in the presence of impurity. In this regard, the effect of dot radius, stoichiometric ratio, impurity and incident optical intensity on the refractive index changes have been investigated for the transitions between higher energy states...

NONLINEAR OPTICAL PROPERTIES OF NOVEL NANOSTRUCTURED ION IMPLANTED AND LASER ABLATED SILICON USING FEMTOSECOND PULSE EXCITATION by Elaine N. Lalanne The study of the nonlinear optical properties of novel nanostructured ion implanted and laser ablation of Silicon is motivated by the need for materials that exhibit large values of the real part of the third order nonlinear susceptibility (x (3)Re...

The refractive index of GaAs has been measured in the wavelength range from 0.97 to 17 mm, which covers nearly the entire transmission range of the material. Linear and quadratic temperature coefficients of the refractive index have been fitted to data measured between room temperature and 95 °C. In the midinfrared, the refractive index and temperature dependence are obtained from analysis of e...

Ultrafast laser processing applications need fast approaches to assess the nonlinear propagation of the laser beam in order to predict the optimal range of processing parameters in a wide variety of cases. We develop here a method based on the simple monitoring of the nonlinear beam shaping against numerical prediction. The numerical code solves the nonlinear Schrödinger equation with nonlinear...

The third-order nonlinear optical properties and optical limiting studies of donor substituted hydrazone derivatives were investigated using the single beam Z-scan technique at 532nm.The calculated values of nonlinear refractive index ,third-order nonlinear optical susceptibility and second order molecular hyperpolarizability are of the order of esu 11 10 , esu 13 10 and esu 31 10 respectively....

We study experimentally two-dimensional periodic photonic lattices optically imprinted in photorefractive nonlinear media, and explore the effect of anisotropy on the induced refractive-index patterns. The orientation anisotropy is demonstrated by comparing square and diamond lattices, while the polarization anisotropy is shown to distinguish ordinarily and extraordinarily polarized light. In p...

We present a method of measurement of the extraordinary refractive index dispersion in MIR for periodically and aperiodically poled nonlinear crystals with unknown or uncertain periods. The method is based on the spontaneous parametric down-conversion and is useful for the crystals with domain structure formed directly in the process of growth by Czochralski technique. As an example we measure ...