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Electronic Structures of Antiperovskite Superconductor MgCNi$_3$ and Related Compounds

J. H. Shim·S. K. Kwon·B. I. Min
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Abstract

Electronic structure of a newly discovered antiperovskite superconductor MgCNi$_3$ is investigated by using the LMTO band method. The main contribution to the density of states (DOS) at the Fermi energy $E_{\rm F}$ comes from Ni 3$d$ states which are hybridized with C 2$p$ states. The DOS at $E_{\rm F}$ is varied substantially by the hole or electron doping due to the very high and narrow DOS peak located just below $E_{\rm F}$. We have also explored electronic structures of C-site and Mg-site doped MgCNi$_3$ systems, and described the superconductivity in terms of the conventional phonon mechanism.

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J. H. Shim, S. K. Kwon, B. I. Min. 2001-10-22. Electronic Structures of Antiperovskite Superconductor MgCNi$_3$ and Related Compounds. https://arxiv.org/abs/cond-mat/0110448

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