Ali H. AL-Hamdani; Alaa H. Ali; Mariam H. Mohamed
Abstract
In this research, the spectral characteristics and the nonlinear optical properties for the mixing of Rhodamine dyes (Rh6G, RC, and RB) were determined at different concentrations ( ...
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In this research, the spectral characteristics and the nonlinear optical properties for the mixing of Rhodamine dyes (Rh6G, RC, and RB) were determined at different concentrations ( 1×10-5,2×10-5,5×10-5,7×10-5, and 1×10-4 mole/L) at room temperature. The spectral characteristics were studied by recording their absorption and fluorescence spectra. The intensity of absorption increased and fluorescence decreased when increasing concentration which in agreement with Beer – Lambert Law. It was observed that this mixing had a wide spectral range. The quantum efficiency decreased while the radiative life time and the fluorescence life time increased when increasing the concentration. Nonlinear optical properties were measured by using Z-Scan technique, using (CW) continuous Nd: YAG laser with frequency doubled wavelength (532nm) with output power (100 mW). The obtained nonlinear properties results of the mixture (R6G, RC, and RB) showed a negative nonlinear refractive index for concentrations (7×10-5, and 1×10-4 mole/L ) while the concentrations (1×10-5,2×10-5, and 5×10-5 mole/L ) showed a positive nonlinear refractive index, also this mixing showed two photon absorption behavior for all concentrations. The origin of optical nonlinearity in the dye may be attributed to laser-heating induced nonlinear effect.
