Ultrafast photoinduced mechanical strain in epitaxial BiFeO3 thin films

Abstract

We studied ultrafast dynamics and photoinduced mechanical strain of BiFeO3 thin films by dual-color transient reflectivity measurements (Delta R/R). Anisotropic photostriction in BiFeO3 is found to be mainly driven by the optical rectification effect. Results of the photostriction at various thicknesses show that the estimated sound velocity along [110] direction of BiFeO3 is 4.76 km/s. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4734512]