Year: 2025
Type: article
Abstract: Chirality is ubiquitous in nature and manifests in a wide range of phenomena including chemical reactions, biological processes, and quantum transport of electrons. In quantum materials, the chirality of fermions, given by the relative directions between the electron spin and momentum, is connected to the band topology of electronic states. This study shows that in structurally chiral materials like CoSi, the orbital angular momentum (OAM) serves as the main driver of a nontrivial band topology in this new class of unconventional topological semimetals, even when spin-orbit coupling is negligible. A nontrivial orbital-momentum locking of multifold chiral fermions in the bulk leads to a pronounced OAM texture of the helicoid Fermi arcs at the surface. The study highlights the pivotal role of the orbital degree of freedom for the chirality and topology of electron states, in general, and paves the way towards the application of topological chiral semimetals in orbitronic devices.
Source: Advanced Materials
Institutions: Forschungszentrum Jülich, University of Duisburg-Essen, Ernst Ruska Centre, Johannes Gutenberg University Mainz, Jülich Aachen Research Alliance, National Taiwan University, National Taipei University of Technology, Research Center for Applied Science, Academia Sinica, Institute of Atomic and Molecular Sciences, Academia Sinica, Academia Sinica, University of California, Davis
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $6,070
Awards: G2095278010, G2508743010, TRR 173: Spin+X: Der Spin in seiner kollektiven Umgebung, G3180218165, G3874802554, G7276484245, Verbundprojekt 05K2019 - XFEL-k-Spin-multi-D: Vollständige 8D Photoelektronenspin- und Impulsmikroskopie zur umfassenden Dynamikanalyse in Quantenmaterialien am XFEL. Teilprojekt 3., TRR 288: Elastisches Tuning und elastische Reaktion elektronischer Quantenphasen der Materie (ELASTOQMAT)
OpenAlex ID: W4410035812