ABSTRACTA systematic study of nonlinear optical properties of silicon nanocrystals (Si-nc) grown by plasma enhanced chemical vapor deposition (PECVD) is reported. Nonlinear optical refraction and absorption have been measured by z-scan technique at three different time regimes and at different wavelengths to investigate both the thermal and electronic responses. For this purpose three different laser sources have been used. Different behaviors, as expected from the theory, for different pump pulse durations are observed.
AbstractFerroelectric potassium niobate thin films have been deposited by conventional, low pressure metalorganic chemical vapor deposition on several types of oxide substrates. The films were epitaxial with a c-axis orientation normal to the substrate. Atomic force microscopy revealed a surface roughness of 1 - 4 nm. Transmission electron microscopy showed the film/substrate interface to be semi-coherent with lattice misfit accommodated by misfit dislocations. The nonlinear optical properties of the KNbO3 films were measured by a transmission technique. The room temperature, effective second order nonlinear coefficient was 13 pm/V.
The present work aims to study the second-order NLO properties of m-AD and p-AD regioisomers. The βtot value of p-AD is larger than that of m-AD. Significantly, the external electric field effectively regulates the βtot values (0–3.70 × 104 a.u.) of p-AD.
Linear and nonlinear optical properties of Si nanocrystals in SiO2 deposited by plasma-enhanced chemical-vapor deposition