Magnetic and dielectric properties of pure and ion doped RCrO3 nanoparticles

摘要

Using a microscopic model and the Green's function technique the magnetic and dielectric properties of YCrO3 and GdCrO3 nanoparticles (NPs) are studied and compared with the bulk properties. Due to different surface exchange interaction constants the magnetization in YCrO3 increases whereas in GdCrO3 decreases with decreasing particle size. The size dependence of the coercive field in GdCrO3 NPs is also discussed. The bulk dielectric constant E in YCrO3 is smaller than that in NPs, whereas in GdCrO3 is observed the opposite behavior. The magnetic field influences E in YCrO3 NPs which is an indirect evidence for a strong magnetoelectric coupling. The effects of ion doping on E are also studied.