Synthesis of bulk FeTe1−xSex (x = 0.1−0.5) at ambient pressure

• Main Authors: Lim, Edmund Hua Hang, Tan, K. Y., Liew, Josephine Ying Chyi, Awang Kechik, Mohd Mustafa, Shaari, Abdul Halim, Chen, Soo Kien, Tan, Kar Ban, Qi, Xiaoding
• Format: Article
• Language: English
• Published: Springer 2015
• Online Access: http://psasir.upm.edu.my/id/eprint/42217/1/Synthesis%20of%20bulk%20FeTe1%E2%88%92x%20Se%20x%20%28x%20%3D%200.1%E2%88%920.5%29%20at%20ambient%20pressure.pdf; http://psasir.upm.edu.my/id/eprint/42217/; http://link.springer.com/article/10.1007%2Fs10948-015-3108-4
• Institution: Universiti Putra Malaysia

In this study, polycrystalline samples with nominal composition FeTe1−xSe x (x=0.1−0.5) were synthesized by solid-state reaction method at ambient pressure. In order to minimize oxidation, argon gas flow was maintained throughout the heat treatment. The phase formation of FeTe1−xSe x samples was checked by X-ray diffraction (XRD). The polycrystalline FeTe1−xSe x samples were indexed to a tetragonal structure with space group of P4/nmm. The lattice parameters a- and c-axes shrink significantly with the substitution of Se. As shown by the scanning electron microscope (SEM) images, the samples developed a plate-like grain structure gradually with the increase of Se concentration. Measurements of temperature dependence of magnetic moment showed that the onset of superconducting transition temperature, T c, increased with Se concentration. The T c is about 10.6 and 13.5 K for x= 0.1 and 0.5, respectively. All the samples exhibit ferromagnetic behavior as shown by the field-dependent magnetization measured at room temperature.