Superconductivity in the presence of disorder in skutterudite-related La${}_3$Co${}_4$Sn${}_{13}$ and La${}_3$Ru${}_4$Sn${}_{13}$ compounds; electrical transport and magnetic studies

A. Slebarski, M. M. Maska, M. Fijalkowski +2

La${}_3$Co${}_4$Sn${}_{13}$ and La${}_3$Ru${}_4$Sn${}_{13}$ were categorized as BCS superconductors. In a plot of the critical field $H_{c2}$ vs $T$, La${}_3$Ru${}_4$Sn${}_{13}$ displays a second su…