Biaxial strain induces a phase transition from a pseudo-rhombohedral (R) to pseudo-tetragonal (T) phase in BiFeO3 (BFO) thin films. Using optical second harmonic generation, we measure the nonlinear optical d ij coefficients at a fundamental wavelength of 1550 nm for R and T-BFO thin films. A large increase of the dij magnitudes is observed for T-BFO in comparison to R-BFO. The dij magnitudes for T-BFO were measured to be: | d33| = 18.1 ± 2.4, |d31| = 60.8 ± 8.1, and |d15| = 47.0 ± 4.2, and for R-BFO: | d 33| = 15.1 ± 2.1, |d31| = 8.5 ± 1.2, |d 15| = 0.9 ± 0.1, and |d22| = 18.7 ± 2.6 (pm / V). The strain-enhanced nonlinear optical properties of T-BFO thin films make them potentially useful for optical applications.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)