Magnetic structure of a new Kagome topological semimetal Ni3In2Se2

Kagome metals, with a frustrated sub-lattice, are ideal hosts for many exquisite quantum phenomena. Taking the kagome-metal Co3Sn2S2 for example,there is an interaction between topological state and spin waves, and the distribution and number of Weyl points are affected by its strong anisotropic magnetoelastic coupling effect and special magnetic structure. Therefore, the role of magnetic structure and magnetic excitations is crucial for the transport behaviors in topological materials. Recently, analogous Black Holes in type-III Dirac semimetal Ni3In2X2 (X= S, Se) is a new class of candidate materials for ideal topological semimetals, which are kesterite-type compounds, similar with the Co3Sn2S2 compound. So far there are no experimental reports on the magnetic ground state of Ni3In2Se2. Here we propose to do neutron diffraction experiments on Ni3In2Se2 to explore the magnetic structure and crystal structure in different temperature regions. Transport measurements indicate that Ni3In2Se2 has an antiferromagnetic order with Ni spins primarily aligned along the ab plane, another a weak ferromagnetism along the c axis probably exists.We apply 5 days of beamtime at the single crystal diffractometer SXD to complete this study.