Two new two-photon absorption (TPA) molecules, named SK-G1 and NT-G1, are synthesized and the photo- physical characteristics are investigated by using linear absorption spectra, one-photon fluorescence spectra and ...Two new two-photon absorption (TPA) molecules, named SK-G1 and NT-G1, are synthesized and the photo- physical characteristics are investigated by using linear absorption spectra, one-photon fluorescence spectra and two-photon excited fluorescence spectra. Both the compounds exhibit TPA properties, and the TPA values determined by z-scan measurement are 10 GM and 39 GM for SK-G1 and NT-G1, respectively, at wavelength 80Ohm. Time-resolved spectroscopic techniques are employed to further explore the excited state dynamics of NT-G l with larger TPA cross section. The research results show that there is an ultrafast intraband energy transfer process (about 3ps) before the formation of charge transfer state with a relatively long lifetime.展开更多
We propose a new formula to describe the dynamics of holographic grating formation under low intensity pulse exposures in cationic photopolymers, in which the dark reaction contributes dominantly to the grating streng...We propose a new formula to describe the dynamics of holographic grating formation under low intensity pulse exposures in cationic photopolymers, in which the dark reaction contributes dominantly to the grating strength. The formula is based on the living polymerization mechanism and the diffusion-free approximation. The analytical solution indicates that the grating formation time depends on the termination rate constant, while the final grating strength depends linearly on the total exposure energy. These theoretical predictions are verified experimentally using the Aprilis HMC-400μm photopolymer. The results can provide guidelines for the control and optimization of the holographic recording conditions in practical applications.展开更多
基金Supported the Leading Academic Discipline Programme (T0104), the National Natural Science Foundation of China under Grant Nos 10374020 and 10674031, and the Seventh Graduate Students Innovation Foundation of Fudan University.
文摘Two new two-photon absorption (TPA) molecules, named SK-G1 and NT-G1, are synthesized and the photo- physical characteristics are investigated by using linear absorption spectra, one-photon fluorescence spectra and two-photon excited fluorescence spectra. Both the compounds exhibit TPA properties, and the TPA values determined by z-scan measurement are 10 GM and 39 GM for SK-G1 and NT-G1, respectively, at wavelength 80Ohm. Time-resolved spectroscopic techniques are employed to further explore the excited state dynamics of NT-G l with larger TPA cross section. The research results show that there is an ultrafast intraband energy transfer process (about 3ps) before the formation of charge transfer state with a relatively long lifetime.
基金Supported by the State Key Fundamental Research and Development Programme of China under Crant No G1999033001, and the National Natural Science Foundation of China under Grant No 60277011.
文摘We propose a new formula to describe the dynamics of holographic grating formation under low intensity pulse exposures in cationic photopolymers, in which the dark reaction contributes dominantly to the grating strength. The formula is based on the living polymerization mechanism and the diffusion-free approximation. The analytical solution indicates that the grating formation time depends on the termination rate constant, while the final grating strength depends linearly on the total exposure energy. These theoretical predictions are verified experimentally using the Aprilis HMC-400μm photopolymer. The results can provide guidelines for the control and optimization of the holographic recording conditions in practical applications.