학술논문

Anisotropic strain, magnetic properties, and lattice dynamics in self-assembled multiferroic CoFe2O4-PbTiO3 nanostructures.
Document Type
Article
Source
Journal of Applied Physics. 2014, Vol. 115 Issue 13, p134317-1-134317-6. 6p. 1 Diagram, 4 Graphs.
Subject
*ANISOTROPY
*NANOSTRUCTURES
*CRYSTAL lattices
*LATTICE dynamics
*PHONONS
Language
ISSN
0021-8979
Abstract
We investigate the anisotropic stress dependent magnetic and phonon behaviors in self-assembled CoFe2O4-PbTiO3 (CFO-PTO) nanostructures deposited on SrRuO3 buffered SrTiO3 substrates of various thickness. The increased vertical compressed stress with increasing thickness enhances the vertical magnetic anisotropy of CFO while gradually reducing the vertical polarization of PTO. By applying the magnetic-field dependent Raman scattering, the CFO-A1g and T2g(1) phonon frequencies shift oppositely because of the magnetostriction. Moreover, the PTO-A1 mode intensities anomalously enhance and the A1 and E mode frequencies, respectively, increase and decrease, which prove the existence of the stress-mediated magnetoelectric (ME) effect. This study shows that the ME transmission process is dominated by interfacial stress, which is critical for enhancing the ME efficiency. [ABSTRACT FROM AUTHOR]