Self-defocusing and nonlinear absorption resulting from two-photon-excited free charge carriers were observed in polycrystalline ZnSe at the low power density of ~ 30 MW/cm2 by use of the Z-scan technique with nanosecond laser pulses. The total carrier absorption cross section and the variation of refractive index per unit of photoexcited carrier density were estimated to be 0.80 ± 0.10 × 10−18 cm2 and 0.60 ± 0.15 × 10−21 cm3, respectively.
|Number of pages||3|
|Publication status||Published - 1994 Aug|
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics