The linear and nonlinear properties of Si thin films upon Si wafers made by the use of laser ablation are presented. The linear absorption of the films clearly showed a peak at 9.8 μm (1020 cm-1), whereas the peak at 9.04 μm (1070 cm-1) from the asymmetric Si-O-Si vibration mode was absent. Raman spectroscopy data show a typical 4-cm-1 downshift with respect to the Si line. The nonlinear measurements were performed with a tunable free-electron laser. The nonlinear absorption at λ = 9.2 μm was measured to be approximately 2, 25, and 5 times larger than the nonlinear absorption at λ = 9.0 μm, λ = 9.4 μm, and λ = 9.6 μm, respectively.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of the Optical Society of America B: Optical Physics|
|State||Published - 1999|
All Science Journal Classification (ASJC) codes
- Statistical and Nonlinear Physics
- Atomic and Molecular Physics, and Optics