Focal volume Control Using Structured Illumination Sources

ended

In optics, one of the important fundamental challenges is the quest for new methods to increase the spatial resolution over the natural diffraction limit of the optical system. Typically, in most of the laser-based micromachining techniques, the spatial resolution is improved by using high numerical aperture lenses in combination with short wavelengths, relying on multiphoton absorption, and working near to the modification threshold to decrease effectively the focal volume and therefore the minimum feature size. Thus, the control of the focal volume dimensions will strongly influence the limits of the system resolution, constituting a demanding and non-trivial task. Near-field optical methods presents promising approaches for this aim. The interest lies in the near-field properties; in this extremely small scale, the optical field is evanescent rather than propagating, so it is not subject of the same diffraction limit and can therefore be concentrated to smaller volumes. Considering this, the present proposal main objective will focus on the evaluation and implementation of the necessary conditions to modify and control the focal volume dimensions in an optical system combining the near-field phenomena induced with different illumination methods. The project will include the development of experiments and simulations for the understanding of the propagation of shaped beams in a particular optical system. The obtained results will be then applied for the nanoprocessing of materials with femtosecond laser pulses. This proposal emphasize in both the transfer of knowledge to the host institutions and the training of the candidate in well-stablished advanced techniques towards the development of the candidate’s career in optics. The multidisciplinary nature of this proposal will strengthen international cooperation, a key initiative of the Innovation Union. This kind of project design is in line with the European strategy for Research and Innovation.