The department uses neutron and X-ray diffraction and spectroscopy as well as optical spectroscopy and Raman scattering to explore the structure and dynamics of materials with strong electron correlations. We also have a strong effort in the development of new spectroscopic methods. As the close collaboration between experimentalists and theorists is essential for the progress in this field, a small theory group operates within the department.
The macroscopic properties of materials with strongly correlated electrons are influenced not only by atomic-scale spin and charge correlations, but also by emergent domain structures on sub-micrometer length scales. Neutron Larmor diffraction and dilatometry have yielded new insights into the mechanisms driving the formation of mesoscopic magnetic and structural domains in the antiferromagnetic parent compound of a high-temperature superconductor.
The electronic structure of iridium oxides has long been known as closely analogous of the one of the cuprate high-temperature superconductors. However, most iridium oxides are insulating, and it has proven difficult to inject charge carriers by doping. Photoemission experiments on an iridium oxide surface that was doped by proximity to a metallic monolayer have now uncovered an energy gap of d-wave symmetry, one of the hallmarks of high-temperature superconductivity.