Altermagnetism and Unconventional Magnetic Orders in Quantum Materials

Organizers:

Riccardo Comin, Massachusetts Institute of Technology
Rafael Fernandes, University of Illinois Urbana-Champaign
Karin Rabe, Rutgers University
Jeroen van den Brink, Leibniz Institute for Solid State and Materials Research

Magnetism is one of the most widely investigated quantum states of matter, as it provides a unique window into the collective microscopic behavior of electronic degrees of freedom. Proposals for novel types of magnetic order have historically triggered intense research efforts in the condensed matter physics community, from Landau’s and Néel’s proposals of antiferromagnets in the 1930s and 1940s to Anderson’s proposal of spin liquids in the 1970s. More recently, in 2022, a new framework was proposed to classify collinear magnetic phases using the mathematical tool of spin groups, which sparked a flurry of research activity on unconventional magnetic phases. Among these unconventional magnetic phases, one state has received significant attention from various communities in condensed matter physics: altermagnets. Defined by their invariance with respect to combined rotation and time reversal, one of the main appeals of altermagnetic states is that they share similar properties with both antiferromagnets (a vanishing net magnetization) and ferromagnets (a spin-split band structure). On the one hand, these properties make altermagnets promising for applications in spintronics. On the other hand, they reveal close connections to important open problems in diverse condensed matter systems. This rich connectivity between different areas of condensed matter physics and altermagnetism is accompanied by a remarkable versatility in the types of materials that realize this phase of matter. The recent surge of interest in altermagnetism and, more generally, in unconventional magnetism, makes this a timely topic for an Aspen Winter Conference. The unique format of this conference will provide an ideal opportunity to bring together this vast and diverse community to find common ground and discuss the latest progress in the field, the open problems, ongoing challenges, and new research directions. Featured topics include: new materials realization of altermagnetism; thermodynamic, transport and spectroscopic signatures of altermagnetism in candidate systems; p-wave magnets and other non-collinear unconventional magnetic phases; impact of electronic correlations in altermagnetic phases; topological phenomena enabled by unconventional magnetism; interplay between altermagnetism and superconductivity.