Tuning magnetism of ScMn₆Sn₆ by Ga doping

The presence of the Dirac and flat bands in Kagome materials has attracted much of the attention of materials scientists. Recently, RMn₆Sn₆ (R= Sc, Y, and Rare Earths) materials that crystalize in the MgFe₆Ge₆ structure have demonstrated exotic physics arising from the intraplanar ferromagnetic (FM) Kagome nets formed by Mn-ions. The magnetism in this class of materials exhibits ferrimagnetic, antiferromagnetic, and helical orderings. With our focus on tuning the magnetism of this class of compounds, we have synthesized ScMn₆Sn₆ single crystals with Ga doping on the Sn sites. The temperature and field-dependent magnetization results show that a low doping concertation such as ~5 % can extend the helical phase up to 417 K from 370 K in the parent compound, while the increased doping concentration of 22 % suppresses the interplanar AFM correlations resulting in a ferromagnetic to paramagnetic transition at 370 K. The combination of magnetic and electrical transport measurements has been utilized to map out the magnetic phase as a function of Ga doping concentration. In our talk, we will discuss our attempt to understand the increase in the stability of the helical phase up to higher temperatures and finally reaching a ferromagnetic ground state with increasing Ga doping.