Strikingly reduced critical field in Ti-doped Kagomé YMn6Sn5.6Ti0.4 single crystal with large topological Hall effect

Abstract

The Kagomé layered YMn6Sn6 alloy reveals large anomalous and topological Hall effects, implying tremendous application potential in spintronics devices. However, high critical magnetic field (the applied field corresponding to topological hall resistivity maximum) is likely to be a stumbling block to its practical application. In this work, a series of YMn6Sn6-xTix (x = 0, 0.4, 0.8, 1, 1.2) single crystals were prepared, in which the substitution of Ti for Sn sites is adopted to modify the exchange interaction between Mn layers in YMn6Sn6 alloy. The magnetic configurations and topological Hall effect are controlled resultantly. For YMn6Sn5.6Ti0.4 alloy, especially, the critical field reduces strikingly to less than 1T from near 4T or even higher [Sci. Adv. 6 (2020) eabe2680, https://doi.org/10.1126/sciadv.abe2680 and Phys. Rev. B 103 (2021) 014416, https://link.aps.org/doi/10.1103/PhysRevB. 103.014416]. What is more important, the topological Hall resistivity still remains relatively large value, ∼0.706 μΩ∙cm. In addition, large anomalous Hall conductivity of 55.7 Ω−1cm−1 is obtained in YMn6Sn5.6Ti0.4.