Determination of finite ferromagnetic moments and origin of unexpected magnetic anisotropy in a collinear magnetoelectric antiferromagnet

A nonreciprocal magnon is a phenomenon where magnetic excitation propagates asymmetrically in real space, holding significant potential for technological applications in magnonics. However, its realisation is uncommon. In this project, we employ a single-crystal neutron diffraction technique to investigate successive magnetic transitions resulting from competing magnetic exchanges and anisotropies. We aim to determine a noncollinear magnetic order in a honeycomb antiferromagnet, a candidate material for the new type of nonreciprocal magnon.