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1.
研究了高压大电流SF6激光触发开关在使用过程中透镜污染的问题,通过对激光触发开关中被污染透镜透过率的测量、透镜表面附着物的分析和透镜使用寿命的数据积累,总结出氟化氢的腐蚀和开关粉尘附着是造成激光开关透镜透过率降低、以致失效的主要原因。通过三种激光触发开关结构参数分析和开关运行数据的比较,认为采用氟化钙透镜、低吸水性绝缘材料、选择轴向绝缘V/N型辅助间隙多电极开关结构、铜钨合金电极、脱水处理等措施,可以降低氟化氢和粉尘的产额,从而增加开关的工作寿命。 相似文献
2.
Optical switches are useful for various optical systems. This paper describes a new form of optical transmission system, using 1 × 6 optical switch with built-in optical multiplexer. The insertion loss of the optical switch was 3.1 dB (including filter loss of 1.4 dB). This switch is useful for a traffic monitoring system, and its transmission characteristics were measured. The measured signal-to-noise ratio is 44 dB when the switch is applied to a 2-km video transmission line. 相似文献
3.
Quantum key distribution (QKD) is being studied as a way to provide unconditionally secure communications. Several experiments have shown its feasibility. However, most experiments have used a point-to-point occupied optical link. In order to use QKD for secure communications on a real network, it is preferable to be able to change parties on demand and to have quantum transmission and ordinary optical transmission share the optical network. In this work, QKD through a silica-based planar lightwave circuit (PLC) 8 × 8 non-blocking matrix switch was investigated. We found that an interferometer type switch can work even for a single-photon-level light and that a multi-user QKD network can be constructed using a silica-based PLC 8 × 8 non-blocking matrix switch. In addition, single-photon-level transmission and ordinary optical transmission can share the same 8 × 8 non-blocking matrix switch, so which shows the possibility of sending quantum signals through current optical networks. 相似文献
4.
Optical switches are useful for various optical systems. This paper describes a new form of optical transmission system, using 1 × 6 optical switch with built-in optical multiplexer. The insertion loss of the optical switch was 3.1 dB (including filter loss of 1.4 dB). This switch is useful for a traffic monitoring system, and its transmission characteristics were measured. The measured signal-to-noise ratio is 44 dB when the switch is applied to a 2-km video transmission line. 相似文献
5.
Surface photovoltage spectroscopy and thermally stimulated contact potential difference measurements are reported for real ZnS surfaces. The measurements allow the determination of the surface states existing via two different processes, i.e. optical excitation of carriers into and from the existing surface states. Changing the surface condition by annealing at 350°C produces different electronic features which are attributed to different bondings at surface vacancy sites. Furthermore, annealing changes the polarity of the surface photovoltage. 相似文献
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By applying nonequilibrium Green's function formalism combined with first-principles density functional theory, we investigate the electronic transport properties of a 1,3-diphenyltriazene-based optical molecular switch. The molecule that comprises the switch can convert between the cis and the trans forms upon photoexcitation. The transmission spectra of two forms are remarkably distinctive. Theoretical results show that the current through the trans form is significantly larger than that through the cis form, which suggests that this system has attractive potential application in future molecular switch technology. 相似文献
8.
The electrical relaxation in composite textures based on poly(dodecanamide) filled with polyamide fibers has been investigated using dielectric relaxation and thermally stimulated current measurements over wide ranges of frequencies and temperatures. The mechanisms of electrical relaxation in the range of the structural transition and at interfaces in the composite are established. 相似文献
9.
Abstract Highly Cu+ doped KCl and KBr polycrystalline films were investigated in the range of 1020-1021 cm?3 Cu+ concentration. Several techniques were used to obtain the optical and structural properties, as optical absorption and transmittance, electronic microscopy (SEM), X-ray diffraction and ellipsometry. The Cu+ off-center effect is still present in the films, as determined by optical and thermally stimulated depolarization current measurements (TSDC). The films were obtained by thermal evaporation, and the corresponding doping Cu-halide is introduced in the same evaporating crucible. Samples with diverse concentrations, ranging from nominal 1 to 10% mole, were prepared. The increase of Cu+ concentration results in an improved cyrstallynity of the grains, with higher density and a better transmittance of the film above 350 nm. Optical application as UV filter device can be considered. 相似文献
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11.
V. Kh. Il’yasov A. N. Lachinov A. V. Moshelev A. F. Ponomarev 《Physics of the Solid State》2008,50(3):568-572
The temperature dependences of the parameters of charge carriers in thin films of an electroactive poly(diphenylenephthalide) polymer are investigated in the range preceding the thermally stimulated electronic switching (110–400 K). The thermally stimulated current spectra and current-voltage characteristics are measured in the same temperature range. The parameters of charge carriers are estimated in the framework of the model of injection currents limited by the space charge. It is revealed that the charge carrier mobility decreases with an increase in the temperature in the range from 110 to 400 K. A correlation between the temperature behavior of the current-voltage characteristics and the thermally stimulated current spectra is established. The possible contribution of the Pool-Frenkel effect is considered, and the inference is made that the electric field plays an important role in the thermally stimulated electronic switching. 相似文献
12.
Laser-excited techniques were used to investigate the optical properties of bismuth germanate crystals. Absorption, reflectivity, excitation, emission, lifetime, time-resolved fluorescence, photoconductivity, thermally stimulated conductivity measurements were performed at various temperatures on single crystals of different origins.The absorption is shown to occur in bismuth and germanate centers while both intrinsic and perturbed Bi3+ ions together with impurities contribute to the total fluorescence.The emission mechanism at room temperature involves a thermally activated energy migration, and at low temperature localized emitting centers. Formation of deep holes in the wide emission band at room temperature reveals saturation effects on various luminescent centers, promoted by energy migration. Trapped exciton models are proposed to explain the excited state dynamics occurring at low and room temperature. 相似文献
13.
A. F. Ponomarev V. A. Krasilnikov M. Vasiliev A. N. Lachinov 《Technical Physics》2003,48(11):1493-1495
Electronic switching in poly(diphenylenephthalide) due to the thermal ionization of electron traps is studied. The method
of thermally stimulated current and the method of thermally stimulated depolarization current are used. A correlation between
spectra obtained by the two methods is established. The results are interpreted by using the temperature dependence of IR
absorption spectra taken under conditions similar to those under which thermally stimulated phenomena are observed. Comparing
data obtained, we assign electron traps to specific molecular groups of the polymer and infer the importance of the surplus
space charge critical concentration for the onset of the high-conductivity state in the polymer. 相似文献
14.
《Journal of Physics and Chemistry of Solids》2007,68(5-6):948-952
The effects of light- and thermally stimulated interdiffusion in Se/As2S3 nanomultilayers (NML) with modulation period of 6–9 nm fabricated by pulsed laser deposition (PLD) and by the method of cyclic thermal evaporation (CTE) of the Se and As2S3 components were investigated by means of direct low-angle X-ray diffraction (LAXRD) measurements and by indirect methods of optical measurements. More pronounced nano-granular structure is characteristic for PLD samples but at the same time the interfaces are essentially sharpened, the periodicity and the initial blue-shift of the optical absorption edge are better in comparison with CTE samples. Somewhat less efficient interdiffusion and changes of optical parameters i.e. amplitude-phase recording in PLD samples in comparison with CTE ones may be caused by different deposition conditions, ratio of sub-layer's thickness and their structure, eventually by changes in chemical composition. 相似文献
15.
In NaCl:S2-, KC1:S2 and NaF:02-(i) optical absorption and emission spectra and (ii) electric conductivity measurements show that after suitable heat treatment the bivalent anion impurities are paired with anion vacancies. Conventional dielectric absorption measurements and sensitive measurements of thermally stimulated depolarizing (t. s. d.) currents (ionic thermocurrent) have failed to detect the presence of bivalent anion-anion vacancy dipoles in these crystals. We suggest that derealization or sharing of the electron of the bivalent impurity ion, possibly with the vacancy, considerably reduces the dipole moment. 相似文献
16.
Characteristics of optical gratings on Si/SiGe heterostructures for switchable optical band-pass filters will be discussed. The grooves of the gratings have an angle of 45° to the propagation of light. The bandwidth can be as low as 0.2 nm. By reducing the refractive index of the SiGe layer due to injected free carriers it is possible to move the transmission band to lower wavelengths. In dense wavelength division multiplexing (DWDM) systems transmission channels can be selected by tuning the current. Therefore, the structure can be used as an electronic adjustable switch. 相似文献
17.
V. B. Kapustyanyk B. I. Turko M. R. Panasyuk G. A. Lubochkova D. L. Voznyuk 《Journal of Applied Spectroscopy》2011,78(4):610-613
We have studied the temperature variation of the intrinsic absorption edge for ZnO:Li films obtained by high-frequency magnetron
sputtering. We have observed anomalous behavior of the optical bandgap width in the vicinity of the temperature of a ferroelectric
phase transition at T = 327 K. For the first time, we have observed the appearance of this phase transition on the thermally
stimulated depolarization (TSD) current curves. 相似文献
18.
We report results obtained from thermally stimulated current and capacitance measurements of metal-SiO-metal structures having different metals for the electrodes. Dependence of relaxed charge on the polarized electrode suggests the existence of space charge near the metal-insulator interface. The measurements of capacitance under superimposed DC voltages support this interpretation and show that space charge is not negligible at high fields. The density of lacalised states evaluated from the data is of the order of 1017 cm?3 相似文献
19.
Second-harmonic generation in Ge(20)As(25)S(55) glass irradiated by an electron beam 总被引:4,自引:0,他引:4
Second-harmonic generation was observed in Ge(20)As(25)S(55) chalcogenide glass irradiated by an electron beam. The second-harmonic intensity increased with increasing electron-beam current and accelerating voltage. The second-harmonic generation in Ge(20)As(25)S(55) glass was caused by the space-charge electrostatic field that was generated by irradiation of an electron beam. Second-order nonlinearity X((2)) as great as 0.8 pm/V was obtained. The results of measurements of thermally stimulated depolarization current indicated that the glass was poled in the thin layers of its surface (several micrometers) and that the nonlinearity was stable. 相似文献
20.
In this paper, a study is made of radiation damage in silicon p n diodes produced by low dose neutron irradiation, and a comparison is made with the results of earlier work on carbon irradiated diodes. Particular emphasis is placed on the effects of damage on the I/V characteristics of the diodes. The physical properties of the damage are studied by means of thermally stimulated current measurements, and further information is obtained from the temperature dependence of the reverse leakage. 相似文献