TY - JOUR
KW - Thin films
KW - Transmission electron microscopy
KW - Scanning electron microscopy
KW - Electron microscopy
KW - Electric fields
KW - Multiferroics
KW - Polarization
KW - Ferroelectric materials
KW - BiFeO3
KW - Ferroelectricity
KW - Antiferromagnetics
KW - High resolution transmission electron microscopy
KW - Antiferromagnetism
KW - Dichroism
KW - Ferroelectric films
KW - Scanning probe microscopy
KW - Antiferroelectricity
KW - Magnetic materials
KW - Phase structure
KW - X-ray absorption
KW - Antiferroelectrics
KW - Spin-charge-lattice coupling
KW - Strain engineering
AU - D Chen
AU - C.T Nelson
AU - X Zhu
AU - C.R Serrao
AU - J.D Clarkson
AU - Z Wang
AU - Yuan Gao
AU - S.-L Hsu
AU - L.R Dedon
AU - Z Chen
AU - D Yi
AU - H.-J Liu
AU - D Zeng
AU - Y.-H Chu
AU - J F Liu
AU - D.G Schlom
AU - Ramamoorthy Ramesh
AB - A strain-driven orthorhombic (O) to rhombohedral (R) phase transition is reported in La-doped BiFeO3 thin films on silicon substrates. Biaxial compressive epitaxial strain is found to stabilize the rhombohedral phase at La concentrations beyond the morphotropic phase boundary (MPB). By tailoring the residual strain with film thickness, we demonstrate a mixed O/R phase structure consisting of O phase domains measuring tens of nanometers wide within a predominant R phase matrix. A combination of piezoresponse force microscopy (PFM), transmission electron microscopy (TEM), polarization-electric field hysteresis loop (P-E loop), and polarization maps reveal that the O-R structural change is an antiferroelectric to ferroelectric (AFE-FE) phase transition. Using scanning transmission electron microscopy (STEM), an atomically sharp O/R MPB is observed. Moreover, X-ray absorption spectra (XAS) and X-ray linear dichroism (XLD) measurements reveal a change in the antiferromagnetic axis orientation from out of plane (R-phase) to in plane (O-phase). These findings provide direct evidence of spin-charge-lattice coupling in La-doped BiFeO3 thin films. Furthermore, this study opens a new pathway to drive the AFE-FE O-R phase transition and provides a route to study the O/R MPB in these films. © 2017 American Chemical Society.
BT - Nano Letters
DO - 10.1021/acs.nanolett.7b03030
LA - eng
M1 - 9
N1 - cited By 26
N2 - A strain-driven orthorhombic (O) to rhombohedral (R) phase transition is reported in La-doped BiFeO3 thin films on silicon substrates. Biaxial compressive epitaxial strain is found to stabilize the rhombohedral phase at La concentrations beyond the morphotropic phase boundary (MPB). By tailoring the residual strain with film thickness, we demonstrate a mixed O/R phase structure consisting of O phase domains measuring tens of nanometers wide within a predominant R phase matrix. A combination of piezoresponse force microscopy (PFM), transmission electron microscopy (TEM), polarization-electric field hysteresis loop (P-E loop), and polarization maps reveal that the O-R structural change is an antiferroelectric to ferroelectric (AFE-FE) phase transition. Using scanning transmission electron microscopy (STEM), an atomically sharp O/R MPB is observed. Moreover, X-ray absorption spectra (XAS) and X-ray linear dichroism (XLD) measurements reveal a change in the antiferromagnetic axis orientation from out of plane (R-phase) to in plane (O-phase). These findings provide direct evidence of spin-charge-lattice coupling in La-doped BiFeO3 thin films. Furthermore, this study opens a new pathway to drive the AFE-FE O-R phase transition and provides a route to study the O/R MPB in these films. © 2017 American Chemical Society.
PB - American Chemical Society
PY - 2017
SP - 5823
EP - 5829
T2 - Nano Letters
TI - A Strain-Driven Antiferroelectric-to-Ferroelectric Phase Transition in La-Doped BiFeO3 Thin Films on Si
VL - 17
SN - 15306984
ER -