Nonmonotonic particle-size-dependence of magnetoelectric coupling in strained nanosized particles of BiFeO₃.

ABSTRACT: Using high resolution powder x-ray and neutron diffraction experiments, we determined the off-centered displacement of the ions within a unit cell and magnetoelectric coupling in nanoscale BiFeO₃ (≈20-200 nm). We found that both the off-centered displacement of the ions and magnetoelectric coupling exhibit nonmonotonic variation with particle size. They increase as the particle size reduces from bulk and reach maximum around 30 nm. With further decrease in particle size, they decrease precipitously. The magnetoelectric coupling is determined by the anomaly in off-centering of ions around the magnetic transition temperature (T _N ). The ions, in fact, exhibit large anomalous displacement around the T _N which is analyzed using group theoretical approach. It un

SUBMITTER: Goswami S 

PROVIDER: S-EPMC5829220 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature