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Band structure of new superconducting AlB_2-like ternary silicides M(Al_{0.5}Si_{0.5})_2 and M(Ga_{0.5}Si_{0.5})_2 (M= Ca, Sr and Ba)

I. R. Shein·N. I. Medvedeva·A. L. Ivanovskii
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Abstract

The electronic band structures of the new superconducting (with T_c up to 7.7K) ternary silicides M(A_{0.5}Si_{0.5})_2 (M= Ca, Sr, Ba; A= Al, Ga) in the AlB_2-type structure have been investigated using the full-potential LMTO method. The calculations showed that the trend in transition temperatures doesn't follow the changes in the density d-states at the Fermi level and probably is associated with phonon-mode frequencies.

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I. R. Shein, N. I. Medvedeva, A. L. Ivanovskii. 2002-12-03. Band structure of new superconducting AlB_2-like ternary silicides M(Al_{0.5}Si_{0.5})_2 and M(Ga_{0.5}Si_{0.5})_2 (M= Ca, Sr and Ba). https://doi.org/10.1088/0953-8984%2F15%2F33%2F105

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