Electronic properties of superconducting ternary alloys (Ca, Sr, Ba)(Ga1−xSix)2 with AlB2-like structure

The electronic properties of superconducting ternary silicides M(Ga1−xSix)2 with M = Ca, Sr and Ba are studied as a function of x (0.35 ⩽ x ⩽ 0.75) by using density functional calculations within the Korringa-Kohn-Rostoker coherent potential-atomic sphere approximation (KKR-CPA-ASA). Our results show that the changes of density of states from x at the Fermi level in Ca-, Sr- and Ba-containing systems are completely different and are mostly dictated by the Ga and Si states.