%0 Journal Article %K Thin films %K Electron energy loss spectroscopy %K Transmission electron microscopy %K Dissociation %K Multiferroics %K Scanning transmission electron microscopy %K Atoms %K Bismuth %K Electronic structure %K Highly strained %K Atomic-resolution %K Direct imaging %K Fe atoms %K R phase %K Spontaneous polarizations %K T-phase %K Atomic spectroscopy %K Electron energy levels %K Electron scattering %A M.D Rossell %A R Erni %A M.P Prange %A J.-C Idrobo %A W Luo %A R.J Zeches %A S.T Pantelides %A Ramamoorthy Ramesh %B Physical Review Letters %D 2012 %G eng %R 10.1103/PhysRevLett.108.047601 %T Atomic structure of highly strained BiFeO 3 thin films %V 108 %X We determine the atomic structure of the pseudotetragonal T phase and the pseudorhombohedral R phase in highly strained multiferroic BiFeO 3 thin films by using a combination of atomic-resolution scanning transmission electron microscopy and electron energy-loss spectroscopy. The coordination of the Fe atoms and their displacement relative to the O and Bi positions are assessed by direct imaging. These observations allow us to interpret the electronic structure data derived from electron energy-loss spectroscopy and provide evidence for the giant spontaneous polarization in strained BiFeO 3 thin films. © 2012 American Physical Society.