Magnetic topological semimetals LnSbTe ($Ln=\mathrm{lanthanide}$) 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 $Ln\mathrm{S}{\mathrm{b}}_x\mathrm{T}{\mathrm{e}}_{2-x}$. With this motivation, we report the evolution of magnetic properties with Sb-Te substitution in $\mathrm{NdS}{\mathrm{b}}_x\mathrm{T}{\mathrm{e}}_{2-x+\delta }$, $(0\le x\le 1)$. Our work reveals the interesting nonmonotonic change in magnetic ordering temperature with varying composition stoichiometry. In addition, reducing the Sb content $x$ drives the reorientation of moments from in-plane ($ab$-plane) to out-of-plane ($c$-axis) direction that results in the distinct magnetic structures for two end compounds $\mathrm{NdT}{\mathrm{e}}_2$ $\left(x=0\right)$ and NdSbTe $\left(x=1\right)$. Furthermore, the moment orientation in $\mathrm{NdS}{\mathrm{b}}_x\mathrm{T}{\mathrm{e}}_{2-x+\delta }$ 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.

• Received 12 October 2023
• Revised 28 March 2024
• Accepted 22 April 2024

DOI:https://doi.org/10.1103/PhysRevB.109.184429