Uniaxial ferromagnetism in the kagome metal TbV6Sn6

The $R\phantom{\rule{0}{0ex}}{T}_{6}\phantom{\rule{0}{0ex}}{X}_{6}$ family ($R$=rare earth, $T$=transition metal) offers an interplay of magnetism with potentially nontrivial topological kagome band structures. Here, the authors present a new member TbV${}_{6}$Sn${}_{6,}$ which contains a pure vanadium kagome lattice. Thermodynamic, magnetometric, and transport measurements reveal an Ising ferromagnetism of local Tb 4$f$ moments accompanied by an anomalous Hall effect below 4.1 K. The Tb magnetism displays a strikingly large uniaxial anisotropy, which the authors argue originates from 4$f$ crystalline electric field effects in a hexagonal symmetry environment.