Magnetization Measurements at High Temperature on Highly Oriented FeSe 0 . 5 Te 0 . 5 Superconductor

We have studied the high-temperature magnetic properties of a highly oriented FeSe0.5Te0.5 superconducting sample produced by self-flux method. The sample was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), electrical resistivity, and magnetic measurements. The XRD pattern revealed the formation of the desired crystalline phase. In addition, two minority impurity phases, a FeSe orthorhombic phase and another Fe3O4 magnetite phase, were observed. SEM micrographs showed that the sample was formed in stacked lamellas. Resistivity measurement showed that the onset superconducting temperature occurs at \(T_{\mathrm {c}}^{\text {onset} } \sim \) 14 K with a transition width ΔT = 5.5 K. Magnetic measurements at high temperature showed that the FeSe0.5Te0.5 compound presents a ferromagnetic-paramagnetic (FM-PM) phase transition at ∼ 843 K. An anomaly was also observed at ∼ 122 K, which may be associated with the Verwey transition due to the presence of the magnetite phase in the sample.