Magnetic Properties of Chemically Synthesized (La1-xEux)0.67Ca0.33MnO3 Nanoplates
A chemical method with small polymer templates of polyvinyl alcohol is explored to obtain thin nanoplates (30-40 nm thickness) of (La1-xEux)0.67Ca0.33MnO3 of single magnetic domains. These plates consist of thin surface layer. X-ray diffraction reveals formation of a single phase (La1-xEux)0.67Ca0.33MnO3 of an orthorhombic crystal structure after annealing the precursor at 1000°C for 2 h in air. With increasing Eu3+ content, the unit cell volume decreased. At low temperature 10 K, as large coercivity Hc as 95 Oe has been found in x = 0.2 sample in comparison to 36 Oe or 42 Oe for x = 0 or x = 0.1 sample. The surface layer or shell serves as a pinning barrier which supports large Hc-value. The Curie temperature (TC) is decreased from 268 K (x = 0) to 160 K (x = 0.2). A small spin flipping signal is reflected at ~ 40 K in thermomagnetic curves and it has been attributed to spin exchange interaction between core and shell.
Atsushi Suzuki and G. Sundararajan
D. De et al., "Magnetic Properties of Chemically Synthesized (La1-xEux)0.67Ca0.33MnO3 Nanoplates", Advanced Materials Research, Vol. 117, pp. 75-79, 2010