2021/10/22 by V. Yu. Irkhin, Yu. N. Skryabin
Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Fermi surface #Fermion #Ferromagnetism #Invariant (physics) #Massless particle #Mathematics #Paramagnetism #Phase transition #Physics #Quantum #Quantum many-body systems #Quantum mechanics #Topological Materials and Phenomena #Topological order #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1134/s0021364021210013
published as Pis'ma ZhETF 114, 625 (2021); JETP Letters 114, 551-555 (2021) · 4 pages
openalex publication_date 2021/10/22 · arxiv created 2021/10/26 · arxiv updated 2021/11/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The topological transition in the strongly correlated half-metallic ferromagnetic compound Co3Sn2S2 from Weyl semimetal (including chiral massless fermions) to a non-magnetic state is treated. This transition goes with a change in topological invariant, and is accompanied by a nontopological transition from saturated ferromagnetic to paramagnetic state, the minority Fermi surface being transformed from ghost (hidden) to real. A corresponding description is given in terms of slave fermion representation for the effective narrow-band Hubbard model. The system Co3Sn2S2 provides a bright example of coexistence of nontrivial topology and strong low-dimensional ferromagnetism. Comparison is performed with other compounds where frustrations result in formation of a correlated paramagnetic state.