Temperature dependence of phase separation and magnetic anisotropy by electron spin resonance in Pr<Subscript>0.6</Subscript> Ca<Subscript>0.4</Subscript> Mn<Subscript>0.9</Subscript> Ru<Subscript>0.1</Subscript>O<Subscript>3</Subscript>

Electron spin resonance (ESR) measurements have been performed on polycrystalline samples of Pr<Subscript>0.6</Subscript>Ca<Subscript>0.4</Subscript>Mn<Subscript>1-x</ Subscript>Ru<Subscript>x</Subscript>O<Subscript>3</Subscript> (x =0, 0.1). The substitution of Ru in the Mn-site strengthens ferromagnetic interactions due to the double exchange between the Mn<Superscript>3+</Superscript> and Mn<Superscript>4+</Superscript> species and super-exchange between the Ru<Superscript>5+</Superscript> and Mn<Superscript>3+</Superscript> species. The temperature dependence of the ESR spectra indicates development of magnetic phase separation in Pr<Subscript>0.6</Subscript>Ca<Subscript>0.4</Subscript>Mn<Subscript>0.9</ Subscript>Ru<Subscript>0.1</Subscript>O<Subscript>3</Subscript> in contrast with the un-doped sample. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005