Magnetic anisotropy of single-crystal ferromagnetic Ce3RuSn6

Using the Czochralski pulling method, we have grown a single-crystal of orthorhombic Ce3RuSn6 that exhibits a ferromagnetic transition. Here we present electrical resistivity, specific heat, and magnetization measurements of this sample in the temperature range from 2 to 300 K. The electrical resistivity ρ displays a -lnT temperature dependence from 20 K to above the Curie temperature TC = 3 K. At TC, ρ decreases, and the specific heat C exhibits a sharp peak due to the magnetic transition. The magnetization measurements reveal that the magnetization M is highly anisotropic, and the magnetic structure below TC is probably not a simple ferromagnetic structure. When the magnetic field B is applied along the b-axis or the c-axis, M shows a ferromagnetic-like rapid increase or an antiferromagnetic-like cusp anomaly, respectively, at TC. Moreover, for B||c, a metamagnetic-like anomaly appears in the magnetization curve at B = 2.5 T. However, for B||a, M does not exhibit a distinct anomaly at TC. The results indicate that below TC, Ce3RuSn6 has a non-collinear magnetic structure and that the magnetic moments are aligned in the bc-plane.