Most interaction between light and matter relevant to our daily life scales linearly with the incident intensity. However, nonlinear optical processes already begin to occur for light at moderate intensities, becoming more pronounced at higher field strengths. As a consequence, properties of light are modified, manifesting themselves in amplitude, phase, polarization or frequency changes. General examples of nonlinear optical processes are lasing and the generation of coherent light. Important specific examples are frequency conversion, supercontinuum and atto-second pulse generation.The investigation of these processes is the focus of our Collaborative Research Center (SFB/CRC) 1375 "Nonlinear Optics down to Atomic scales (NOA)" which started in July 2019.
NOA focuses on exploring fundamental nonlinear processes of light matter interaction in low-dimensional nanostructures, such as atomically thin layers, nanoparticles and -wires, nanostructured surfaces and molecular assemblies. We will explore quantum phenomena as light-induced tunneling of electrons through metallic nanogaps and field-driven carrier acceleration in plasmonic nanostructures, atomic lattices and 2D-materials. This includes the investigation of the resulting back-action on the electromagnetic field, causing the generation of higher harmonics carrying valuable information about the electronic wavefunctions involved in the interaction.
More information: www.noa.uni-jena.de