We report evidence for ferroelectricity in bismuth manganite epitaxial films from optical second-harmonic generation (SHG). The change in the polar symmetry of SHG signals under external electric fields is correlated to specific changes in the ferroelectric domain microstructures. We also observe giant enhancement of SHG by 3 to 4 orders of magnitude with effective d f∼193 pm/V under electric fields of ∼707 V/mm. The material also exhibits a large third-order nonlinear optical response with nonlinear absorption coefficient α1∼ -0.08 cm/kW and nonlinear refractive index n1∼-0.53×10-9 cm2/W.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Jun 2004|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics