Complicated magnetic structure and its strong correlation with the anomalous Hall effect in Mn3Sn

The large anomalous Hall effect (AHE) has recently been found in noncollinear antiferromagnet $\mathrm{M}{\mathrm{n}}_{3}\mathrm{Sn}$. However, the complex magnetic structure and its correlation with the AHE remain unclear. Here we investigate the magnetic structure of $\mathrm{M}{\mathrm{n}}_{3}\mathrm{Sn}$ completely by means of both the temperature and magnetic field dependence of neutron power diffraction. This study establishes the possible incommensurate magnetic structure models and extracts the temperature evolution of the magnetic moment of the Mn atom over the whole temperature range for $\mathrm{M}{\mathrm{n}}_{3}\mathrm{Sn}$. The large AHE of polycrystalline bulk $\mathrm{M}{\mathrm{n}}_{3}\mathrm{Sn}$ is measured in detail. By comparing the temperature dependence of the spontaneous component of the AHE and the magnetic moment, direct experimental evidence reveals that the triangular antiferromagnetic ordered moment of the Mn atom controls the change in the AHE of $\mathrm{M}{\mathrm{n}}_{3}\mathrm{Sn}$. This study provides the possibility to control the AHE of functional materials via changing the magnetic structure.