Our group pursues experimental nonlinear and ultrafast nano-optics. We want to understand and control the light-matter interaction in solids and at interfaces on nanometer length scales and femtosecond time scales. Combining scanning probe microscopy with ultrashort laser pulse excitation we can access the natural length and time scales of the elementary electronic, vibrational, and structural excitations in matter. This allows us to address the fundamental processes underlying correlated electron phenomena in complex oxides, semiconductor nanostructures, or morphology and dynamics in molecular and polymer nano-composites. We apply concepts of optical antennas and surface plasmon and phonon polaritons to confine light below the diffraction limit, sculpt it on the nanometer scale, control it spectrally, and manipulate its field strength on time scales of a single-optical cycle. We also explore new optical phenomena and forces unique to the optical near-field, including extreme nonlinear optics, and strong light matter interaction.