@article{33487, keywords = {transmission electron microscopy, room temperature, Polarization, ferroelectricity, Ferroelectric polarization, First-principles calculation, scanning transmission electron microscopy, X ray absorption spectroscopy, Experimental evidence, Lone pair electrons, Oxygen octahedra}, author = {J.X Zhang and Q He and M Trassin and W Luo and D Yi and M.D Rossell and P Yu and L You and C.H Wang and C.Y Kuo and J.T Heron and Z Hu and R.J Zeches and H.J Lin and A Tanaka and C.T Chen and L.H Tjeng and Y.-H Chu and Ramamoorthy Ramesh}, title = {Microscopic origin of the giant ferroelectric polarization in tetragonal-like BiFeO3}, abstract = {We report direct experimental evidence for a room-temperature, ∼130μC/cm2 ferroelectric polarization from the tetragonal-like BiFeO 3 phase. The physical origin of this remarkable enhancement of ferroelectric polarization has been investigated by a combination of x-ray absorption spectroscopy, scanning transmission electron microscopy, and first principles calculations. A large strain-induced Fe-ion displacement relative to the oxygen octahedra, combined with the contribution of Bi 6s lone pair electrons, is the mechanism driving the large ferroelectric polarization in this tetragonal-like phase. © 2011 American Physical Society.}, year = {2011}, journal = {Physical Review Letters}, volume = {107}, number = {14}, issn = {00319007}, doi = {10.1103/PhysRevLett.107.147602}, note = {cited By 186}, language = {eng}, }