Magnetic chirality induced by chemical substitution in a chiral-polar antiferromagnet.

Exotic physical phenomena are bound to happen in chiral magnets, since broken space inversion, mirror symmetry and time reversal symmetry often accompany new physical phenomena.$^{\mathrm{\thinspace }}$The Dzyaloshinskii Moriya (\textit{DM}) interactions, allowed by the lattice chirality, could bring about a twist between the magnetic moments and lead to various chiral magnetic structures.$^{\mathrm{\thinspace }}$However, chiral magnets do not necessarily exhibit chiral magnetic structures. For example, the chiral magnet Ni$_{\mathrm{3}}$TeO$_{\mathrm{6}}$ exhibits an achiral collinear antiferromagnetic structure below 52 K. Exploring the new methods that could turn the collinear magnetic structure into chiral magnetic structure in chiral magnets is crucial for studying the exotic chiral physics in this family of materials. Recently, we synthesized high quality single crystals of Co-substituted Ni$_{\mathrm{3}}$TeO$_{\mathrm{6}}$ - NiCo$_{\mathrm{2}}$TeO$_{\mathrm{6}}$. In this talk, we will discuss our recent experimental results of chiral magnet NiCo$_{\mathrm{2}}$TeO$_{\mathrm{6}}$. Our neutron diffraction experiments reveal that an incommensurate helical magnetic structure with spins aligned in the \textit{ab} plane is induced by Co substitution. The results obtained from our polarized neutron diffraction experiments show clear magnetic chirality in the magnetic structure. Our results suggest that chemical substitution is an efficient method for creating chiral magnetic structures in chiral magnets.