Evolution of magnetism in magnetic topological semimetal NdSb_xTe_2-x+δ

Magnetic topological semimetals LnSbTe (Ln = Lanthanide) have attracted intensive attention because of the presence of interplay between magnetism, topological, and electron correlations depending on the choices of magnetic Ln elements. Recently, varying Sb-Te composition has been found to effectively control the electronic and magnetic states in LnSb_xTe_2-x. With this motivation, we report the evolution of magnetic properties with Sb-Te substitution in NdSb_xTe_2-x+δ, (0 ≤ x ≤ 1). Our work reveals the interesting non-monotonic change in magnetic ordering temperature with varying composition stoichiometry, which is likely attributed to the coupling between magnetism and charge density waves. In addition, reducing the Sb content x drives the reorientation of moments from in-plane to out-of-plane direction that results in the distinct magnetic structures for two end compounds NdTe₂ and NdSbTe. Furthermore, the moment orientation in NdSb_xTe_2-x+δ is also found to be strongly tunable upon application of a weak magnetic field, leading to rich magnetic phases depending on the composition stoichiometry, temperature, and magnetic field. Such strong tuning of magnetism in this material establishes it as a promising platform for investigating tunable topological states and correlated topological physics.