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991.
光子晶体光纤的色散特性 总被引:1,自引:0,他引:1
本文用有效折射率模型 ,分析了光子晶体光纤的色散特性 ,定量给出了光子晶体光纤双折射特性与光纤参数之间的关系 ,指出了光子晶体光纤具有多个零色散波长 ,对相关现象作出了合理的解释。 相似文献
992.
简单地推导了相位调制下的单音频率在传输光纤中其功率与光纤色散、光纤距离之间的关系,并介绍了在DWDM系统中可以利用相位调制法进行实时监测色散。此方法对于40GHz系统的色散实时监测提供了很好的参考方法。仿真结果表明,在未考虑光纤非线性效应的情况下有很高的精确性,当考虑非线性效应时,其传输距离会由于传输速率的影响而受到限制。 相似文献
993.
Yu. E. Prazdnikov L. S. Lepnev A. D. Bozhko N. D. Novikov 《Journal of Russian Laser Research》2005,26(3):245-251
The influence of the thickness of an oriented carbyne film on the conductance of a special sample was investigated with an electric field of up to 1.8 ⋅ 106 V/cm applied transverse to the carbon chains. A steplike dependence of the conductance on the thickness was observed. The general shape of the current-voltage characteristics, I ∝ U
2.3, changes to I ∝ U
2 when the thickness corresponding to a rapid change of conductance is attained. The characteristics presumably correspond to the space-charge limited current in the presence or absence of the trap band within the carbyne band gap. We propose the formation of a charge-topological soliton lattice at “magic” thicknesses which results in a layered structure of the film and in a bandlike conduction transverse to the chains. 相似文献
994.
O. Dubos W. Petry J. Neuhaus B. Hennion 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,3(4):447-454
We present inelastic neutron scattering measurements of the low energy and strongly damped phonons in the high temperature
bcc phase of zirconium. These phonons were investigated at different scattering vectors but equivalent phonon wave vectors in different Brillouin zones or along different but equivalent paths in the same Brillouin zone. Neither the observed differences
in intensity nor in line shapes can be explained by the coherent one-phonon scattering law . This leads to an apparent violation of the fundamental symmetry of lattice dynamics. Taking into account the strong anharmonicity
of these phonons, interferences between one- and multi-phonon scattering are held responsible for these effects. Measurements
in different scattering planes reveal that due to the symmetry of the bcc lattice, these effects can only be observed in certain
directions.
Received: 24 December 1997 / Received in final form: 9 March 1998 / Accepted: 19 March 1998 相似文献
995.
Experiments on hydrodynamic and heat transfer behavior of the flow in a twisted curved channel were conducted in a water tunnel and also in two heat exchanger coils tested in a heat exchanger test facility. The flow regime, designated “chaotic advection,” is a subclass of laminar flow with high mixing properties. Preliminary results show that heat transfer is enhanced due to the chaotic trajectories generated in the flow. 相似文献
996.
The effects of the compensation ratio with dispersion post-compensation on nonlinear single channel and WDM systems with 10 Gb/s per channel are numerically investigated. When the transmission signal per channel is 10 Gb/s RZ pulse and the amplifier span is 50 km, proper undercompensation can enhance the performance of the nonlinear single channel system and the nonlinear WDM system. But the enhanced distance of the nonlinear WDM system is not as obvious as that of the single channel system, because the cross-phase-modulation effect plays an important role in the nonlinear WDM system. 相似文献
997.
FINITE ELEMENT SIMULATIONS FOR COMPRESSIBLE MISCIBLE DISPLACEMENT WITH MOLECULAR DISPERSION IN POROUS MEDIA 总被引:1,自引:0,他引:1
CHENHUANZHEN LIQIAN 《高校应用数学学报(英文版)》1996,11(1):17-32
Abstract. We consider a nonlinear parabolic system describing compressible miscible displacement in a porous medium [5]. Continuous time and discrete time Galerkinmethods are introduced to approximate the solution snd optimal H1 error estimatesare obtained. One contribution of this paper is a demonstration of how moleculaxdispersion can be handled. 相似文献
998.
999.
The Darboux transformations for the nonlinear Schrodinger equation and Maxwell-Bloch equations areconstructed. The one-soliton solution and periodic solution are obtained from the different “seeds“. 相似文献
1000.
K. K. Mondal 《Pramana》2004,63(5):1021-1030
For an unmagnetized partially ionized dusty plasma containing electrons, singly charged positive ions, micron-sized massive
negatively charged dust grains and a fraction of neutral atoms, dispersion relations for both the dust-ion-acoustic and the
dustacoustic waves have been derived, incorporating dust charge fluctuation. The dispersion relations, under various conditions,
have been exhaustively analysed. The explicit expressions for the growth rates have also been derived.
International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore, India. 相似文献