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A novel symmetrical charge transfer fluorene-based compound 2,7-bis (4-methoxystyryl)-9, 9-bis (2-ethylhexyl)-9H-fluorene (abbreviated as BMOSF) was synthesized and its nonlinear absorption was investigated using two different laser systems: a 140-fs, 800-nm Ti:sapphire laser operating at 1-kHz repetition rate and a 38-ps, 1064-nm Nd:YAG pulsed laser operating at 10-Hz repetition rate, respectively. Unique nonlinear absorption properties in this new compound were observed that rise from multiphoton absorption. The nonlinear absorption coefficients were measured to be 6.02×10-3 cm/GW (due to two-photon absorption, exciting wavelength is 800 nm) and 3.6×10-20 cm3/W2 (due to three-photon absorption, exciting wavelength is 1064 nm). This new compound possesses strong fluorescence induced by two-photon absorption and obvious three-photon absorption optical limiting effects. 相似文献
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通过对新合成的芴的一种具有对称性衍生物4-2-(7-(4-氨基苯乙烯基)-9,9-二(2-乙基己基)-9H-芴-2-)乙烯基)苯胺(BASF)的DMF溶液的研究,发现其具有很强三光子吸收频率上转换荧光发射特性,实验测出上转换荧光的波长范围是456—775nm,在510nm处的荧光强度与入射光强的三次方成正比.在0.03mol/L的浓度下就有明显的三光子吸收诱导的光限幅效应.非线性吸收系数和吸收截面分别为γ=4.34×10-20cm3/W2和σ3=2.4×10-39cm6/W2.
关键词:
三光子吸收
光限幅
上转换荧光
吸收截面 相似文献
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Reversible Resistance Switching Effect in Amorphous Ge1Sb4Te7 Thin Films without Phase Transformation 下载免费PDF全文
We demonstrate a reversible resistance switching effect that does not rely on amorphous-crystalline phase transformation in a nanoscale capacitor-like cell using Ge1Sb4Te7 films as the working material. The polarity and amplitude of the applied electric voltage switches the cell resistance between low- and high-resistance states, as revealed in the current-voltage characteristics of the film by conductive atomic force microscopy (CAFM). This reversible SET/RESET switching effect is induced by voltage pulses and their polarity. The change of electrical resistance due to the switching effect is approximately two orders of magnitude. 相似文献
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Sb-Bi alloy flms are proposed as a new kind of super-resolution mask layer with low readout threshold power. Using the Sb-Bi alloy film as a mask layer and SiN as a protective layer in a read-only memory disc, the superresolution pits with diameters of 380 nm are read out by a dynamic setup, the laser wavelength is 780 nm and the numerical aperture of pickup lens is 0.45. The effects of the Sb-Bi thin film thickness, laser readout power and disc rotating velocity on the readout signal are investigated. The results show that the threshold laser power of super-resolution readout of the Sb-Bi mask layer is about 0.5 m W, and the corresponding carrier-to-noise ratio is about 20 dB at the film thickness of 50nm. The super-resolution mechanism of the Sb-Bi alloy mask layer is discussed based on its temperature dependence of reflection. 相似文献
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A Feasible Approach to Optical--Electrical Hybrid Data Storage Using Phase Change Material 下载免费PDF全文
We present our experimental results supporting optical-electrical hybrid data storage by optical recording and electrical reading using Ge2Sb2Te5as recording medium. The sheet resistance of laser-irradiated Ge2Sb2 Te5 films exhibits an abrupt change of four orders of magnitude (from 107 to 10^3 Ω/sq) with increasing laser power, current-voltage curves of the amorphous area and the laser-crystallized dots, measured by a conductive atomic force microscope (C-AFM), show that their resistivities are 2. 725 and 3.375 × 10^-3 Ω, respectively, the surface current distribution in the films also shows high and low resistance states. All these results suggest that the laser-recorded bit can be read electrically by measuring the change of electrical resistivity, thus making opticalelectrical hybrid data storage possible. 相似文献