© IFP

We study interactions of electromagnetic radiation with condensed matter in a broad frequency range between static regime and visible light. This is obtained using a combination of several experimental techniques. Depending on the specific frequency range, different excitations can be observed and studied: phonons, magnons, magnetoelectric excitations, relaxation processes. Due to fundamental relation between static and dynamic properties, the observed features in the spectra are directly connected to such static properties like magnetisation, dielectric constant, or static electric polarization. Details of underlying microscopic mechanisms are extracted from magnetic and electric dispersion and absorption phenomena. Broadband optical spectroscopy is therefore a powerful method to reveal fundamental properties of condensed matter such as quantum Hall effect, charge dynamics at the metal-insulator transition, electron spin resonance, magnetoelectric effect, negative refraction in metamaterials, etc.