High-Harmonic Spectroscopy and Holographic Imaging of Semiconductors and correlated materials

High-harmonic generation from solids (SHHG) has established itself as a remarkable tool for probing ultrafast dynamics in matter. Highly non-linear interactions between light and matter characterizing this process allow to study the dynamic change to the electronic and structural properties of solids at very short time scale. In this thesis, we have used SHHG spectroscopy to investigate the insulator-to-metal (IMT) phase transition in correlated materials. These unique materials are extremely attractive for the development of next generation opto-electronic devices, due to their ability to change resistance in reaction to small external perturbations. Therefore, improving our understanding of the exact mechanisms driving these phase transitions is crucial. Measuring the phase of light, as provided by holographic measurements, is necessary in order to fully describe SHHG emission. Therefore, this work also aimed at combining SHHG with holographic imaging in order to develop new metrology techniques for the characterization of nanostructures etched in semiconductors. Transient dynamics in correlated materials were also assessed, using the phase information as an additional probing tool.