Magnetotransport properties of the kagome magnet TmMn6Sn6

A kagome magnet usually hosts nontrivial electronic or magnetic states, drawing great interest in condensed matter physics. In this paper, we report a systematic study on the transport properties of the kagome magnet TmMn6Sn6. The prominent topological Hall effect (THE) has been observed in a wide temperature region spanning over several magnetic phases and exhibiting strong temperature and field dependence. This phenomenon, due to nonzero spin chirality, indicates the possible appearance of nontrivial magnetic states accompanying by strong fluctuations. The planar applied field drives the planar Hall effect and anisotropic magnetoresistivity, exhibiting sharp disconnections in angular-dependent planar resistivity violating the empirical law. By using an effective field, we identify a magnetic transition separating the planar anisotropic magnetoresistivity into two groups belonging to various magnetic states. We extended the empirical formula to scale the field-and temperature-dependent planar magnetoresistivity and provide an understanding of the planar transport behaviors with the crossover between various magnetic states. Our results shed light on the transport effects in the presence of multiple nontrivial magnetic states for a kagome lattice with complicated magnetic structures.