Pressure Study of Pure and Rh‐doped RuSr2GdCu2O8 Magnetic Superconductors
We carried out an investigation of the effect of quasi‐hydrostatic pressures up to 1.2 GPa in pure and Rh‐doped RuSr2GdCu2O8 compounds, by means of measurements of electrical resistivity in magnetic fields up to 9 T. The onset temperatures for superconductivity, and for magnetic order in the undoped RuSr2GdCu2O8 compound are Tc ≈ 50 K, and Tm ≈ 133 K, respectively. The partial substitution of Rh for Ru lowers both these transitions temperatures. However, the effect of pressure for all compositions studied, up to 10% substitution, was to increase both Tc, and Tm. The effect of pressure on the upper critical magnetic field of the pure, and Rh‐doped compounds is discussed.