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1.
A novel technique to overcome the long-term drift and hysteresis of a scanning Fabry–Perot filter was developed and applied to wavelength and power monitoring of DWDM system. By using the comb peaks generated by a temperature-stabilized, near threshold-biased Fabry–Perot diode laser as wavelength reference for the scanning Fabry–Perot filter, wavelength and power measurement accuracy of better than ±10 pm and 0.2 dB, respectively, were achieved. 相似文献
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We have demonstrated all-optical packet add-drop for all-optical packet-switched networks. Intelligent all-optical add-drop of packets is performed, based on all-optical processing of packet headers. The header and payload rates are 5 and 10 Gbits/s, respectively. 相似文献
4.
Broadband wavelength converter based on four-wave mixing in a highly nonlinear photonic crystal fiber 总被引:4,自引:0,他引:4
We demonstrate a 10 Gbit/s nonreturn-to-zero wavelength converter based on four-wave mixing in a 20 m highly nonlinear photonic crystal fiber. The tunable wavelength conversion bandwidth (3 dB) is about 100 nm. The conversion efficiency is -16 dB when the pump power is 22.5 dBm. Phase modulation was not used to suppress the stimulated Brillouin scattering; thus the linewidth of the converted wavelength remained very narrow. The eye diagrams show that there is no additional noise during wavelength conversion. The measured power penalty at a 10(-9) bit-error-rate level is about 0.7 dB. 相似文献
5.
A whole temperature sensor in one package utilizing a fiber Bragg grating (FBG) made in a conventional single-mode fiber and which uses a long-period grating (LPG) made in a photonic crystal fiber is proposed and experimentally demonstrated. The function of the interrogation is that the wavelength change of the FBG with environmental temperature is transferred to the intensity of the output via the LPG. Utilizing the temperature-insensitivity of the LPG in the PCF, the interrogation is stable and enables a cheap and practical temperature measurement system with a wide dynamic range. 相似文献
6.
<正>Two new eudesmane derivatives were isolated from the leaves and flowers of Verbesina virginica,along with the known 6-O-β-E -p-coumaroyl-4α-hydroxyeudesmane(1).Their structures were determined as 6-O-β-Z-p-coumaroyl-4α-hydroxyeudesmane(2) and 6-O-α-E-p-coumaroyl-1β-4α-dihydroxyeudesmane(3) by spectroscopic methods. 相似文献
7.
CM Thaker S Rayaprol Krushna Mavani DS Rana MS Sahasrabudhe SI Patil DG Kuberkar 《Pramana》2002,58(5-6):1035-1039
The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good
example of these properties is (La1−2x
Pr
x
Ca
x
)MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x=0.1, 0.15, 0.2), the T
c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using
X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for
understanding the structural, transport and magnetic properties are discussed in detail. 相似文献
8.
This paper presents an extension of Beale's Quadratic Programming Algorithm to perform parametric analysis on the right hand side element of a single constraint. Specific examples are given to illustrate the utilization of the method for a class of bi-criteria decision problems, where one of the criteria can be formulated as a quadratic function, such as risk, sum of squared deviations or a utility function, and the other one is usually a linear cost or return function which can be treated as a parametric constraint. 相似文献
9.
John W.Grove 《数学物理学报(B辑英文版)》2010,30(2):563-594
This article describes mathematical models for phase separated mixtures of materials that are in pressure and velocity equilibrium but not necessarily temperature equilibrium. General conditions for constitutive models for such mixtures that exhibit a single mixture sound speed are discussed and specific examples are described. 相似文献
10.
For the purpose of constructing novel waveguide gas lasers based on hollow-core fibers, we carried out a series of discharge
experiments and succeeded in obtaining sustained glow discharge of gas in a 150-μm-inner-diameter (i.d.) hollow-core fiber
with the length of 13.7 cm and in a 50-μm-i.d. hollow-core fiber with the length of 2.9 cm by using longitudinal direct current
excitation. A flash glow is also observed in hollow-core photonic bandgap fiber with 20-μm i.d. and 2.6-cm length. Initial
measurements of current–voltage (I–V) characteristics have been carried out for fibers of various hollow-core sizes filled
with various gases at different pressures. Theoretical I–V characteristics are presented and compared with experimental results.
Gas discharges in miniature-bore hollow-core fibers were found to exhibit unique characteristics that are different from the
traditional larger-bore-diameter tubes. The glow-discharge spectrum of helium gas in a 150-μm-i.d. and 8-cm-length hollow-core
fiber is also presented.
PACS 42.55.Wd; 42.55.Lt; 52.80.-s 相似文献