Nanoparticles in oxide and chalcogenide glasses: optical nonlinearities and waveguide fabrication by femtosecond laser pulses

Abstract

The study of nonlinear optical processes, although it is still an area in development, it has been received much attention due to the interest in both generation of new technologies and the basic aspects of the interaction between light and matter. In this context, this PhD project has the objective to study the nonlinear optical properties and the production of waveguides in glassy materials using femtosecond pulses. In the first stage of the project, we intend to study the refractive nonlinear optical response and multi-photon absorption process, spectrally broad (450 nm - 1700 nm) in germanate and tellurite glasses. These glassy systems (XO2-Bi2O3 - PbO with X = Te and Ge), should present high optical nonlinearities due to the presence of highly polarizable ions and, also because their lattice with high refractive index. We will investigate the correlation between the structure and the nonlinear responses of the samples, and we will identify the composition and the range of frequencies in which the material exhibits better performance for photonic applications.At the second stage of the project, we intend to use femtosecond pulses to study the micromachining processes induced by nonlinear interactions in glassy lattice. In this context, we will determine the optimum conditions for micromachining to produce 3D waveguides. This study will be done both germanate and tellurite glasses, which the nonlinear properties will be previously determined, and also in glasses doped with Tb ((CaO-B2O3-Li2O) Tb4O7), which must present magneto-optical properties. From these studies, we intend to produce three-dimensional waveguides inside the bulk of the glasses, as a first step to improve the development of the integrated photonic devices.