Polarized neutron investigation in the mixed-valence compound Sm₃Te₄

Cubic Sm₃Te₄ can be characterized as a semiconducting, inhomogeneous mixed-valence system. No evidence of charge ordering is found at low temperature, indicating that Sm²⁺ and Sm³⁺ ions are randomly distributed on one crystallographic position. The magnetization density of a Sm₃Te₄ single crystal was measured at 1.5 K using polarized neutrons, with a magnetic field applied along [1 1̄ 0]. As the Sm₃Te₄ structure is not centric, the measured flipping ratios have been directly processed by the maximum entropy method and by a least-squares refinement. The two approaches are in agreement: under the action of the magnetic field, the Sm site splits into two subsites, with very different induced magnetization densities. Two possible explanations are proposed.