Large off-diagonal magnetoelectricity in a triangular Co²⁺-based collinear antiferromagnet.

ABSTRACT: Magnetic toroidicity is an uncommon type of magnetic structure in solid-state materials. Here, we experimentally demonstrate that collinear spins in a material with R-3 lattice symmetry can host a significant magnetic toroidicity, even parallel to the ordered spins. Taking advantage of a single crystal sample of CoTe₆O₁₃ with an R-3 space group and a Co²⁺ triangular sublattice, temperature-dependent magnetic, thermodynamic, and neutron diffraction results reveal A-type antiferromagnetic order below 19.5 K, with magnetic point group -3' and k = (0,0,0). Our symmetry analysis suggests that the missing mirror symmetry in the lattice could lead to the local spin canting for a toroidal moment along the c axis. Experimentally, we observe a large off-diagonal magnetoelectric coefficient of 41.2 ps/m that evidences the magnetic toroidicity. In addition, the paramagnetic state exhibits a large effective moment per Co²⁺, indicating that the magnetic moment in CoTe₆O₁₃ has a significant orbital contribution. CoTe₆O₁₃ embodies an excellent opportunity for the study of next-generation functional magnetoelectric materials.

SUBMITTER: Xu X 

PROVIDER: S-EPMC10698043 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature