Electronic phase separation in (La1/3Sm2/3)2/3A1/3MnO3 (A=Ca, Sr and Ba) compounds -: art. no. 10H711

Electrical and magnetotransport properties of (La1/3Sm2/3)(2/3)A(1/3)MnO(3) (A=Ca, Sr, and Ba) compounds, synthesized by the citrate gel route, have been investigated. These compounds crystallize in an orthorhombic structure (space group Pnma). Semiconducting-like behavior is observed only in Ca-substituted sample while Ba and Sr-substituted samples show metal-insulator type transition. The high and weakly temperature dependent magnetoresistance at low temperature, thermal irreversibility in field-cooled and zero-field-cooled magnetization, and nonsaturating magnetization behavior are expected in systems with electronic phase separation. The cationic size disorder by varying alkaline earth ions causes the electronic phase separation. (c) 2005 American Institute of Physics.