Physics Colloquium – Roland Winkler

Standard Model of Electromagnetism and Chirality in Crystals

Roland Winkler, Professor, Department of Physics
Northern Illinois University

Predicting emergent macroscopic characteristics of crystalline solids remains a central challenge in materials physics because conventional approaches often overlook subtle symmetries that dictate complex electric, magnetic, and chiral properties. We addressed this by developing a comprehensive classification that uses symmetry principles to sort crystal structures into five categories of electric and magnetic multipole order and five categories of chirality. Our framework identifies 12 unique types of crystal classes, each possessing distinct physical properties, and accounts for previously overlooked configurations, such as multichirality with four distinct enantiomorphs.