Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

1 Publication

Observation of giant spin-split Fermi-arc with maximal Chern number in the chiral topological semimetal PtGa

Yao, M.; Manna, K.; Yang, Q.; Fedorov, A.; Voroshnin, V.; Schwarze, B. V.; Hornung, J.; Chattopadhyay, S.; Sun, Z.; Guin, S. N.; Wosnitza, J.; Borrmann, H.; Shekhar, C.; Kumar, N.; Fink, J.; Sun, Y.; Felser, C.
Non-symmorphic chiral topological crystals host exotic multifold fermions, and their associated Fermi arcs helically wrap around and expand throughout the Brillouin zone between the high-symmetry center and surface-corner momenta. However, Fermi-arc splitting and realization of the theoretically proposed maximal Chern number rely heavily on the spin-orbit coupling (SOC) strength. In the present work, we investigate the topological states of a new chiral crystal, PtGa, which has the strongest SOC among all chiral crystals reported to date. With a comprehensive investigation using high-resolution angle-resolved photoemission spectroscopy, quantum-oscillation measurements, and state-of-the-art ab initio calculations, we report a giant SOC-induced splitting of both Fermi arcs and bulk states. Consequently, this study experimentally confirms the realization of a maximal Chern number equal to ±4 in multifold fermionic systems, thereby providing a platform to observe large-quantized photogalvanic currents in optical experiments.

Downloads:

  • available with HZDR-Login

Permalink: https://www.hzdr.de/publications/Publ-30950
Publ.-Id: 30950