Effects of substituting Se with Te in the FeSe compound: structural, magnetization and Moessbauer studies

TL;DR

This study investigates how substituting Te for Se in FeSe affects its structure, magnetization, and electronic properties, revealing superconductivity in certain compositions and structural changes with Te content.

Contribution

It provides a comprehensive analysis of structural, magnetic, and spectroscopic effects of Te substitution in FeSe, highlighting the emergence of superconductivity.

Findings

Superconductivity observed at x=0.25, 0.50, 0.75

Lattice parameters increase with Te content

No internal magnetic hyperfine fields detected

Abstract

Polycrystalline samples of FeSe1-xTex (x = 0.00, 0.25, 0.50, 0.75 and 1.00) were synthesized by solid-state reaction to study the effects of substituting Se with Te in the system. The magnetization properties of the resulting compounds were investigated and the crystallographic structures of the samples analyzed through X-ray diffraction. Moessbauer spectroscopy was used to determine the ionic state of the Fe ions and the hyperfine fields. The magnetic susceptibility curves of the samples with x = 0.25, 0.50 and 0.75 show superconducting behavior. The lattice parameters and the cell volume increase monotonically with increasing Te concentration and the Moessbauer spectra reveal the absence of internal magnetic hyperfine fields.