Effect of substitution and heat treatment route on polycrystalline FeSe0.5Te0.5 superconductors

Abstract

The effect of atomic substitution of Te in iron based superconductors FeSe (1: 1 type), which exhibits the simplest crystal structure among the iron-based superconductors, has been investigated in terms of structural, electronic transport, and magnetic properties. Polycrystalline samples with nominal Se: Te in FeSe1-xTex samples for x = 0.5(350)degrees C, 0.5(700)degrees C, 0.6(700)degrees C, and 0.75(700)degrees C were synthesized by the solid-state reaction method. in overall samples, it has been observed that the most superconducting properties seen in x = 0.6(700)degrees C samples, for 0.5(350)degrees C and 0.5(700)degrees C samples latter showed better superconducting properties as dc magnetic susceptibility, ac susceptibility, and resistivity measurements and sample homogeneity. T-c enhancement is well correlated with the Te substitution up to 75 %.