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Consecutive wavelength switching characteristics of a simple, compact, and digitally wavelength-switchable laser based on V-coupled cavities are reported. Wavelength switching through thermal and carrier injection effects is examined. Without using band gap engineering for the tuning section, 26- and 9-channel wavelength switching schemes are achieved via thermal and carrier injection effects, respectively. The performances of these two tuning schemes are then compared. 相似文献
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刘忠 张玉虎 郭应祥 周小红 雷相国 柳敏良 罗万居 何建军 郑勇 潘强岩 甘再国 罗亦孝 T.Hayakawa M.Oshima Y.Toh T.Shizima Y.Hatsukawa A.Osa T.Ishii M.Sugawara 《中国物理 C》2002,26(10):1015-1020
利用420MeV82Se轰击139La引起的深部非弹反应和在束γ谱学方法研究了142Ce的中高自旋激发态.识别出了激发能为2625,2995和3834keV的3个新能级,自旋、宇称分别被指定为8+,9(-)和11(-).发现这些能级非常好地符合N=84偶偶核转晕能级的系统性.利用经验壳模型计算了142Ce的中高自旋激发态的激发能,计算结果比较好地重现了实验值.对它们的结构进行了讨论,表明在142Ce的中高自旋激发态中以单粒子激发为主 相似文献
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我们合成了以不同链长连接的荧光素酯与蒽甲酸酯的四种二元化合物.在溶液中的构象研究表明.链呈不同程度的弯曲.但分子内两个发色团的相互作用是微弱的.激发蒽甲酸酯时,无论是在分子间还是在分子内,其单重态能量几乎都传递给了荧光素酯.激发荧光素酯时,并未观测到分子内的光致电子转移,尽管计算和模型化合物分子间的对照实验都表明它们之间是可以发生这种电子转移的.最可能的原因是这个系列在溶液中,分子内的两个发色平面没有好的匹配,或者说,这些二元化合物在所研究的溶液中,不能满足分子内的光致电子转移对构象的要求. 相似文献
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Two dyads of eosin and porphyrin linked with a semi-rigid (-CH2phCH2-) or flexible (-(CH2)4-) bridge and their reference model compounds were synthesized and characterized The intermoleccular interaction and intramolecular photoinduced singlet energy transfer and electron transfer were studied by their absorp tion spectra,fluorescence emission,excitation spectra and fluorescence lifetime The model compounds,ethyl ester of eosm (EoEt) and porphyrin (PorEt),could form complexes in the ground state.When the eosin moieties in dyads were excited,they could transfer some singlet energy to the porphyrins; in the meantime,they could also ndsce electron transfer between two chromophores.Exciting the porphyrin moieties in dyads could induce electron transfer from eosin moieties to porphyrin moieties.The efficiencies (EnT,ET) and rate constants (kEnT,kET) were related to the polarity of solvents and mutual orientation of the two chromophores in dyads. 相似文献
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