- 作者: 文在川 ; 任孝莊 ; 劉慧文 等
- 作者服務機構: 高雄醫學院化學系
- 中文摘要: The nonlinear absorption and refraction of soluble phthalocyanines and naphthalocyanines have been measured with z-scan technique using 8ns, 532nm laser pulses. The excited-state absorption cross-section and the excited-state refractive-index cross section have been estimated under the consideration of laser induced thermal effect. The excited state absorption induced n/sub 2/ and ReX/sup (3)/ values are in the range of 10/sup -12/ esu. These observed data are enhanced by the concentrations of both metal substituted Pc's and Nc's, but this increment became very small for the metal free phthalocyanine. During the optical limiting experiments, a 25% linear transmitted solution of R/sub 8/ PcH/sub 2/ can limit laser pulses to .ltoreq.120.mu.J from incident energies as high as 2.0mJ, and this limitation moved down to .ltoreq.50.mu.J when replacing R/sub 8/PcCu from P/sub 8/PcH/sub 2/. A similar property has also been observed for the metal substituted naphthalocyanines. The results indicate that both the nonlinear refraction and optical limiting properties should be strongly affected by the metal induced triplet-state nonlinear absorption in both Pc's and Nc's. Moreover, the laser pulses created a self trapped filament inside the solution of this optical limiter, while emitting time-resolved, concentric rings on a projection screen, which could be induced by the thermal lensing effect. The various optical nonlinear properties observed from these materials should make them valuable as an optical limiter.
- 英文摘要: --
- 中文關鍵字: Nonlinear Refraction; Optical Limit; Phthalocyanine; Naphthalene; Nonlinear Optics
- 英文關鍵字: 非線性折射;光限;青素;;非線性光學