The Investigation On Spectrum Controllability Materials And Laser Limiting Conjugated Materials

This paper investigates the technical principles and practicability of novel photoelectric functional materials, and their potential application in electro-optics defense. The controllable spectral properties of materials were studied using PANI derivatives with electrochromics, N*-LC with controllable pitch variation and Er3+/Nd3+co-doped oxyfluoride glasses with Mid-infrared. And the nonlinear optical limiting technology of C60、CNTs、Graphene was also studied.Herein, we report our work progress as follows:(1) PANI and its derivatives films were synthesized by using electrochemical polymerization and electrochemical doping techniques to test the film’s electrochromism. The results showed that diphenylamine sulfonate-doped PANI film exhibits good homogeneity, strong affinity, fast response, and excellent electrochromic performance.(2)6Chiral1,2-propanediol derivatives were prepared, which formed chiral nematic crystals (N*-LC) once doped into a nematic liquid crystal. The N*-LCs with controllable pitch variation were obtained by changing the percentage and enantiomeric excess of the chiral dopants.(3) To modify the competition between different energy states and radioactive/non-radioactive transitions, the fluoride with low phonon energy and Er3+/Nd3+co-doped oxyfluoride were proposed, Er3+/Nd3+co-doped oxyfluoride glasses and Er3+doped oxyfluoride Ceramic glass were prepared. The upconversion and Mid-infrared fluorescence properties of Er3+/Nd3+co-doped oxyfluoride glasses were verified.(4) PANI-MWNTs, PS-MWNTs, PS-C60, PTh-C60compounds were synthesized by the in-situ and emulsion polymerization process, which all showed strong nonlinear absorption and optical limiting with laser pulses of40ps using Z-scan technique at1064nm. The optical limiting mechanism of C6o compounds is the single excited-states reverse saturable absorption. Two main mechanisms of the MWNTs compounds are the nonlinear absorption and induced scattering. The interactions between the conjugated polymers are thought to be significant to improve the nonlinear and optical limiting properties. The optical limiting properties of suspensions of graphene and SWNTs were measured. The results showed a broadband optical limiting effect for nanosecond laser pulses at532nm and1064nm. The tandem limiter based on SWNTs-NMP and G-CB was designed, which exhibits a broadband limiting property for low and high damage threshold. Besides, the optical limiting mechanisms of fullerene and SWNT are also absorption and induced scattering.