The hydrostatic-pressure effect on the superconducting transition temperature (Tc) of the stabilized Sr-based 1:2:3 compounds RSr2Cu2.7Mo0.3Oy with R=Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb has been determined up to 16 kbar. All Tc's are enhanced linearly by pressure at a rather rapid rate (dTc/dP). A drastic jump in dTc/dP vs ionic radius of R occurs near Dy, i.e., dTc/dP∼0.7 K/kbar for small R=Ho, Er, Tm, and Yb, and ∼0.4 K/kbar for the larger R's=Tb, Gd, Eu, and Sm. The results suggest that Cu(1) substitution by Mo is crucial in the stabilization of the Sr-based 1:2:3 compound. Several possibilities for the dTc/dP step detected are advanced.
All Science Journal Classification (ASJC) codes