Effect of pressure on magnetic and transport properties of CaMn1-xRuxO3 (x=0-0.15):: Collapse of ferromagnetic phase in CaMn0.9Ru0.1O3 -: art. no. 024403

Magnetic and transport properties of CaMn1-xRuxO3 (x=0;0.1;0.15) perovskites were investigated in the temperature range 4.2-280 K, magnetic fields up to 15 kOe and hydrostatic pressure up to 12 kbar. It was found that for a substitution of x=0.1, an applied pressure of 12 kbar shifts up the magnetic transition temperature by similar to14 K and simultaneously drastically suppresses the ferromagnetic metallic phase. For x=0.15, the application of pressure reduces transition temperature by about -0.28 K/kbar and suppresses the FM phase in a less pronounced manner. Observed changes in resistivity and magnetoresistance of CaMn0.9Ru0.1O3 are described by suppression of the double-exchange interactions under pressure. They are discussed in the context of the phase separation and valency effects.