Nonlinear absorption in a novel metallophthalocynine compound (C_(12)H_(25)O)_(8)PcPb was investigated by the Zscan technique with the irradiation of 8ns laser pulses at the wavelength of 532nm. The large optical limi...Nonlinear absorption in a novel metallophthalocynine compound (C_(12)H_(25)O)_(8)PcPb was investigated by the Zscan technique with the irradiation of 8ns laser pulses at the wavelength of 532nm. The large optical limiting response was observed. The nonlinear absorption cross section was obtained by the simulation with a simplified rate equation model in which excited triplet-triplet state absorption is dominant. The excited-state absorption cross section and its effective ratio to the ground-state absorption cross section are larger than those of C_(60). The attenuation factor for (C_(12)H_(25)O)_(8)PcPb is 2.5 times larger than that of C_(60), which is induced by the heavy atom lead interposition.展开更多
Spatial and temporal changes of temperature in a novel polymer are investigated by using the Z−scan technique under ns laser pulse excitation.According to the open aperture Z−scan experimental results,the nonlinear ab...Spatial and temporal changes of temperature in a novel polymer are investigated by using the Z−scan technique under ns laser pulse excitation.According to the open aperture Z−scan experimental results,the nonlinear absorption coefficient of the polymer is determined.By solving the diffusion equation of heat conduction induced by optical absorption,the spatial and temporal changes in temperature are obtained.This change in temperature drives the photo-acoustic and electromagnetic wave propagating in the polymer and induces the change in refractive index,which serves as a negative lens,and the closed aperture Z−scan shows a peak and valley profile.Based on the numerical calculation,we achieve a good fit to the closed-aperture Z−scan curve with an optimized nonlinear refractive index.This consistency attests the existence of temperature change in the solution,and the Z-scan technique is suitable to investigate this change in temperature.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.292682001 and 29832030。
文摘Nonlinear absorption in a novel metallophthalocynine compound (C_(12)H_(25)O)_(8)PcPb was investigated by the Zscan technique with the irradiation of 8ns laser pulses at the wavelength of 532nm. The large optical limiting response was observed. The nonlinear absorption cross section was obtained by the simulation with a simplified rate equation model in which excited triplet-triplet state absorption is dominant. The excited-state absorption cross section and its effective ratio to the ground-state absorption cross section are larger than those of C_(60). The attenuation factor for (C_(12)H_(25)O)_(8)PcPb is 2.5 times larger than that of C_(60), which is induced by the heavy atom lead interposition.
文摘Spatial and temporal changes of temperature in a novel polymer are investigated by using the Z−scan technique under ns laser pulse excitation.According to the open aperture Z−scan experimental results,the nonlinear absorption coefficient of the polymer is determined.By solving the diffusion equation of heat conduction induced by optical absorption,the spatial and temporal changes in temperature are obtained.This change in temperature drives the photo-acoustic and electromagnetic wave propagating in the polymer and induces the change in refractive index,which serves as a negative lens,and the closed aperture Z−scan shows a peak and valley profile.Based on the numerical calculation,we achieve a good fit to the closed-aperture Z−scan curve with an optimized nonlinear refractive index.This consistency attests the existence of temperature change in the solution,and the Z-scan technique is suitable to investigate this change in temperature.