In this study we revealed the effect of scandium doping on the electronic and superconducting properties of the MgB2 compound. Calculations demonstrate that Sc substitutes for Mg atoms, acting as an electron donor. Mg substitution diminishes the density of states in the σ-band and attenuates the electron-phonon coupling, thereby elucidating the reduction in critical temperature. Simultaneously, Sc-induced microstructural defects serve as effective pinning centers, thereby improving the critical current density. The established separation of electronic and microstructural effects allows for the targeted modification of MgB2 properties.
Dikhtievskaya et al. (Tue,) studied this question.