Ralph Claessen

Prof. Ralph Claessen is the Head of Chair for Experimental Physics IV at the University of Würzburg, Germany. His research focuses on experimental condensed matter physics, with expertise in electronic structure analysis of complex solids, surfaces, and interfaces. He leads a team investigating topological and strongly correlated quantum materials, epitaxial thin film growth, and advanced spectroscopic techniques like synchrotron-based electron and x-ray spectroscopy.

His group explores phenomena such as spin-charge separation in quasi-one-dimensional conductors, topological edge states, and the interfacial properties of oxide heterostructures. Recent work includes developing momentum microscopy techniques at synchrotron facilities, studying graphene-intercalated quantum spin Hall systems, and advancing epitaxial growth methods for novel 2D materials.

Key research directions include stabilizing high-temperature quantum spin Hall insulators, understanding chirality in kagome metals, and characterizing atomic-scale structures of nanowires. Claessen’s lab collaborates on cutting-edge instrumentation, such as hybrid photoelectron momentum microscopes, to probe electronic properties with unprecedented spatial and momentum resolution.

His team also investigates memristive effects in oxide heterostructures and the electronic response of materials under extreme conditions. Ongoing projects aim to bridge theory and experiment through advanced spectroscopic and microscopy techniques, targeting applications in quantum computing and spintronics.