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981.
In this paper the calculation of resonance frequencies and threshold gains of distributed feedback (DFB) lasers with strong modulations is discussed. The theory is based on the Floquet solutions of a complex Hill differential equation. The dispersion relation of the above solutions is shown to be of importance for the behaviour of the resonances of the DFB laser. 相似文献
982.
导出了两种材料构成的多量子阱光波导的模式截止方程,并讨论了Si衬底上生长的应变GexSi1-x/Si多量子阱光波导的模式截止特性。 相似文献
983.
REN Ping-Da PAN Shi-Feng DONG Ting-Wei WU Shi-HuiDepartment of Chemistry Pudan University Shanghai China 《中国化学》1996,14(5):462-466
In the presence of active metal bismuth (Bi) which was prepared from the combination of bismuth trichloride and sodium borohydride,aldehydes have been found to react with allyl bromide in aqueous media,and the corresponding homoallylic alcohols were obtained in excellent yields with high chemo-and stereoselectivity. 相似文献
984.
Optical solitary waves that propagate in a Kerr medium exhibiting a power-law nonlocal response are studied analytically. The first-principles stability analysis based on quantum field theory shows that within the whole range of the exponent (the fractal dimension) the solitary wave can be stabilized. 相似文献
985.
在非线性J—C模型系统中制备“薛定谔猫态” 总被引:4,自引:0,他引:4
证明在含有克尔介质的双光子J-C模型系统中通过对原子的测量可以制备“薛定谔猫态”。选择适当的测量时间,原子初态及非线性系数,即可产生偶相干态,奇相干态和Y-S相干态。 相似文献
986.
This paper reviews a microscopic model of basic electron-hole pair excitation processes in strongly confined semiconductor quantum dots (QD) and their influence on the optical QD properties. The effects of valence band mixing, Coulomb interaction, and surface polarization are taken into account. The exciton and biexciton wave functions and energies are obtained using a numerical diagonalization method. The computed optical spectra, such as absorption, gain, pump-probe, and two-photon absorption, agree well with experiments. 相似文献
987.
A scheme is developed for analysing the interaction between a foundation and a nonlinear rock and soil medium, in which the
foundation is considered as a linear elastic body and a typical boundary integral equation method (BIEM) is employed. On the
basis of taking the nonlinear properties of the medium into account, a perturbation BIEM is developed. The fundamental equations
for the nonlinear coupling analysis are formulated, and typical problems are solved and discussed by the present method. 相似文献
988.
S. Karshenboim U. Jentschura V. Ivanov G. Soff 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,2(3):209-215
We present an analytical evaluation of radiative corrections in exotic atoms induced by the one-loop electronic vacuum polarization.
We evaluate corrections to the energy levels, to the wave function (at the origin) and to the hyperfine structure. We treat
all corrections analytically within a non-relativistic approximation. Agreement is found with a few available numerical results.
The analytical treatment allows to determine the asymptotic forms of the corrections in the limit of a small atomic radius,
which for the atomic systems considered corresponds to a large mass of the constituent particle as compared to the electron
mass. The asymptotics can be verified using the effective charge approach.
Received: 28 January 1998 / Accepted: 13 March 1998 相似文献
989.
990.
S. Mukherjee 《Il Nuovo Cimento C》1996,19(2):237-243
Summary The neutrino emission from supernova 1987A is being studied by taking into consideration the effect of the magnetic field
present in the star. The magnetic field generates an anisotropic feature in the local space-time, which in turn leads to the
cancellation of the axial-vector part of the neutrino current. The interaction cross-section of these neutrinos in the course
of their interaction with matter on Earth has an inverse square energy dependence. The present work presents the calculations
based on this changed cross-section that relates to predictions of the expected number of events at KAMIOKANDE on the basis
of the Mont Blanc signal. It might be interesting to take a look into the implications of these results.
The author of this paper has agreed to not receive the proofs for correction. 相似文献