Drastic effect of the Mn-substitution in the strongly correlated semiconductor FeSb2.

International Workshop on Itinerant-Electron Magnetism

Kassem, Mohamed A.^1,2 ; Tabata, Yoshikazu^1 ; Waki, Takeshi^1 ; Nakamura, Hiroyuki^1

Department of Materials Science and Engineering, Kyoto University, Kyoto

606-8501, Japan^1

Department of Physics, Assiut University, Assiut

71515, Egypt^2

关键词: Chemical compositions;    Electronic transport;    Mn concentrations;    Narrow-gap semiconductors;    Powder X ray diffraction;    Solubility limits;    Structure parameter;    Wavelength dispersive X-ray spectroscopies;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/868/1/012019/pdf
DOI  :  10.1088/1742-6596/868/1/012019

来源: IOP

【 摘 要 】

We report the effects of Mn substitution, corresponding to hole doping, on the electronic properties of the narrow gap semiconductor, FeSb2, using single crystals of Fe1-xMnxSb2grown by the Sb flux method. The orthorhombic Pnnm structure was confirmed by powder X-ray diffraction (XRD) for the pure and Mn-substituted samples. Their crystal structure parameters were refined using the Rietveld method. The chemical composition was investigated by wavelength-dispersive X-ray spectroscopy (WDX). The solubility limit of Mn in FeSb2is xmax∼ 0.05 and the lattice constants change monotonically with increasing the actual Mn concentration. A drastic change from semiconducting to metallic electronic transports was found at very low Mn concentration at x ∼ 0.01. Our experimental results and analysis indicate that the substitution of a small amount of Mn changes drastically the electronic state in FeSb2as well as the Co-substitution does: closing of the narrow gap and emergence of the density of states (DOS) at the Fermi level.