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991.
We consider a new model for passive mode locking in a semiconductor laser comprising a set of delay differential equations. Bifurcations leading to the appearance and break-up of the mode-locking regime are studied numerically. 相似文献
992.
993.
Stephen Z. D. Cheng 《Journal of Thermal Analysis and Calorimetry》1997,50(5-6):907-910
994.
12 , 169 (1987). Reasonably good agreements in the peak output power and laser efficiency have been achieved. Model calculations
also predict that an efficiency as high as 2.7% can be obtained once the conditions of the above-mentioned experiments have
been optimized. From the consideration that the skin depth effectively limits the absorption length of the microwave pumping
and hence the excitable volume, it is concluded that high input power densities (>2 MW/cm3) and higher gas pressures (between 3 and 10 atm) are the preferable conditions to achieve higher efficiency. Preliminary
calculations on CCl4 containing XeCl gas mixtures show that improvement in laser efficiency by several folds may be achieved as a result of the
higher intrinsic efficiency of excimer formation.
Received: 23 September 1996 / Revised version: 25 March 1997 相似文献
995.
996.
We investigate numerically the interaction between two light beams, initially monochromatic, during the excitation of solitary waves in quadratically non-linear media. We show that the result of the interaction is strongly dependent on soliton oscillations occurring during excitation, generating a new class of threshold phenomena. 相似文献
997.
998.
T Kloks D Kratsch C.K Wong 《Journal of Algorithms in Cognition, Informatics and Logic》1998,28(2):272-289
We present two algorithms solving the minimum fill-in problem on circle graphs and on circular-arc graphs in timeO(n3). 相似文献
999.
Yu. G. Abov D. S. Denisov N. O. Elyutin S. K. Matveev Yu. I. Smirnov A. O. Éidlin F. S. Dzheparov D. V. L’vov 《Journal of Experimental and Theoretical Physics》1998,87(6):1195-1200
The asymptotic behavior of the spectra for large values of the scattering vector for the case of elastic multiple small-angle
neutron scattering (SANS) is investigated theoretically and experimentally. An expansion of the spectrum in terms of the reciprocal
of the magnitude of the momentum transfer is obtained taking account of the influence of the instrumental line. It is shown
that, to within some factor, the leading term of the expansion is identical to the differential single-scattering cross section
averaged over a statistical ensemble of particles; several subsequent terms in the expansion are calculated and the range
of applicability of the resulting expressions is determined. The asymptotic behavior of the multiple SANS spectrum is measured,
using a two-crystal neutron spectrometer, for samples of an HTSC ceramic, the alloy Fe-Ni, and Al powder. The agreement between
the experimental results and the theoretical predictions is analyzed.
Zh. éksp. Teor. Fiz. 114, 2194–2203 (December 1998) 相似文献
1000.
G. G. Bondarenko A. I. Bazhin A. P. Korzhavyi V. I. Kristya R. D. Aitov 《Technical Physics》1998,43(9):1121-1122
The electric field at the surface of a charge spot created by an ion beam on a dielectric coating of a target is calculated.
An expression is obtained which relates the surface potential of the insulator to the potential of the collector corresponding
to saturation of the collector secondary-electron current. It permits determination of the potential drop across the oxide
layer of a cold cathode without introducing complications in the construction of the experimental apparatus.
Zh. Tekh. Fiz. 68, 126–128 (September 1998) 相似文献