(Seminarium odwołane\Talk cancelled!) Direct Laser Writing: An opportunity for integrated optical components?

My talk will be focused on the possibility to realize three-dimensionally localized modifications within the bulk of transparent materials. When intense ultrashort pulses are tightly focused into the transparent material, the intensity in the focal volume can become high enough to initiate nonlinear absorption processes. This localized energy deposition results in permanent structural changes inside the sample without affecting the surface. Depending on the processing parameters, either isotropic refractive index changes, self-organized sub-wavelength structures leading to form birefringence or microvoids can be generated in the focus. In this presentation a short overview on the fundamentals and different applications of femtosecond volume structuring will be given. In this framework, we recently demonstrated a new type of waveguides, for which the positive refractive index modification is sustained by the laser-induced photochemistry of silver-containing glasses. Some of the inner features of the refractive index structures and associated waveguides show mesoscale dimensions of a few hundreds of nanometers, which is of interest for produce sub-wavelength modifications. We will present recent results concerning the mask-less fabrication of first-order Bragg grating in the red/near-IR range