PtBi2 is a polymorphic system with interesting electronic properties. Here we report optimized crystal growth and structural characterization of pyrite-type and trigonal modification of PtBi2. Selected area electron diffraction, X-ray powder diffraction and further Rietveld refinement confirms that trigonal PtBi2 crystallizes in non-centrosymmetric P31m space group, pyrite-type PtBi2 in Pa3ˉ space group. Series of Pt1−xRhxBi2 samples was obtained for x=0,0.03,0.35 in the trigonal PtBi2 structure. These Pt1−xRhxBi2 compounds become superconducting where critical temperature increases from Tc=600 mK for x=0 up to Tc=2.7 K for x=0.35. Furthermore we calculate the electronic band structure, using the structure parameters obtained. The calculated density of states (DOS) shows a minimum for the stochiometric compound at the Fermi level. These findings warrant further research by broader array of experimental techniques, as well as the effect of the substitution on the non-trivial band structure.
@article{arxiv.2002.03976,
title = {Polymorphic PtBi2: Growth, structure and superconducting properties},
author = {G. Shipunov and I. Kovalchuk and B. R. Piening and V. Labracherie and A. Veyrat and D. Wolf and A. Lubk and S. Subakti and R. Giraud and J. Dufouleur and S. Shokri and F. Caglieris and C. Hess and D. V. Efremov and B. Büchner and S. Aswartham},
journal= {arXiv preprint arXiv:2002.03976},
year = {2020}
}