Tuning TbMn₆Sn₆ via Cr doping

Kagome materials have gained much attention due to the coexistence of flat bands and Dirac points in their band structures which may become topologically non-trivial with the addition of spin-orbit coupling. The RT₆X₆ (R = rare earth, T = transition metal, X = Si, Ge, Sn) kagome family is of particular interest due to the kagome layers being comprised solely of T. The ferrimagnet TbMn₆Sn₆ was recently claimed to be a quantum-limit Chern topological magnet [1], but the physics of this system is still being debated [2]. We present data on single crystals of Tb(Cr_xMn_1-x)₆Sn₆ showing that doping with the largely non-magnetic Cr effectively tunes this system. The ferrimagnetic transition temperature and subsequent spin-reorientation temperature seen in TbMn₆Sn₆ both decrease with doping, the anomalous Hall effect is significantly altered with doping, and for a large range of x an exchange bias is observed that exists up to 100K. These responses provide evidence that doping can play a large role in engineering the magnetic and topological phases of the RT₆X₆ family.



[1] J.-X. Yin et al., Nature 583, 533-536 (2020)

[2] D. C. Jones et al., arXiv: 2203.17246