Enhancement of ferromagnetic and dielectric properties of lanthanum doped bismuth ferrite nanostructures

Cylindrical-shaped multiferroic Bi(1-x)La(x)YeO(3) (x = 0.0, 0.05, 0.1 and 0.15) were synthesized successfully by hydrothermal method. All samples were found to be rhombohedrally distorted perovskite structure. Diameter of the cylindrical particles reduces from similar to 450 nm for x = 0.0 to similar to 100 nm for x = 0.1 prepared under the same conditions. The Neel temperature as well as the dielectric constant: was also found to increase with the increase in lanthanum content. Lanthanum doping also enhanced the magnetic properties. Magnetization measurements above room temperature show a significant increase in magnetization at around 400 degrees C. Enhanced magnetic properties due to lanthanum doping are caused by the breakage of spin cycloid as observed by electron spin resonance study. (C) 2012 Elsevier Ltd. All rights reserved.