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991.
CsLiB6O10晶体光学参变振荡器的光学特性 总被引:3,自引:0,他引:3
根据三波耦合过程中的能量和动量守恒、晶体的塞耳迈耶尔色散方程,通过数值模拟计算了213nm作CLBO光学参变振荡抽运源时,分别得到了在Ⅰ类和Ⅱ类相位匹配时参量光调谐范围为237~289nm、807~2793nm和404~2800nm。获得了在Ⅰ类匹配时的单谐振或双谐振腔的CLBO光学参变振荡转换效率都大于同等条件下的BBO光学参变振荡,Ⅱ类匹配时,CLBO晶体的转换效率略小于BBO晶体,但是CLBO光学参变振荡转换效率的最大值较BBO光学参变振荡出现于更短的紫外波段。从理论上证明了CLBO晶体是优质的深紫外透光波段非线性光学晶体。 相似文献
992.
各向同性谐振子径向基本算符的应用 总被引:2,自引:1,他引:1
利用基本算符D/Dρ,ρ,1/ρ对本征函数RNL的递推关系和任意力学量算符对函数RNL的作用结果,容易求得力学量的矩阵元和平均值等。 相似文献
993.
994.
Bohlin transformation for a circular singular oscillator in a constant magnetic field is considered. It is shown that this transformation leads to a two-dimensional Kepler problem with an additional centrifugal potential from the constant magnetic field whose strength decreases inversely proportional to the distance from the center of attraction of the system. The energy spectrum of the considered system is obtained. 相似文献
995.
The one‐dimensional harmonic oscillator potential plus a term of the form λ / xα is known as the spiked oscillator potential; it constitutes a very interesting system because of its difficulties to accept perturbative and variational solutions for certain regimes of the α parameter. By the use of a numerical method, we obtain accurate energy eigenvalues and eigenfunctions for a wide range of λ values and a few α values. The accuracy of the present results is by much higher than previously published results. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 相似文献
996.
Bifurcations are discussed by the criterion of top Lyapunov exponent. Based on the local map and Kaminski’s algorithms, a general formulation of the top Lyapunov exponents is proposed for non-linear vibro-impact oscillators with Gaussian white noise perturbation. The analytical results are verified by phase portraits and bifurcation diagrams for a classical stochastic Duffing vibro-impact oscillator. Both results are consistent. 相似文献
997.
In this paper we present a bifurcation analysis of two periodically forced Duffing oscillators coupled via soft impact. The controlling parameters are the distance between the oscillators and the difference in the phase of the harmonic excitation. In our previous paper http://arXiv:1602.04214 (P. Brzeski et al. Controlling multistability in coupled systems with soft impacts [11]) we show that in the multistable system we are able to change the number of stable attractors and reduce the number of co-existing solutions via transient impacts. Now we perform a detailed path-following analysis to show the sequence of bifurcations which cause the destabilization of solutions when we decrease the distance between the oscillating systems. Our analysis shows that all solutions lose stability via grazing-induced bifurcations (period doubling, fold or torus bifurcations). The obtained results provide a deeper understanding of the mechanism of reduction of the multistability and confirmed that by adjusting the coupling parameters we are able to control the system dynamics. 相似文献
998.
This paper considers two prototypical strongly nonlinear oscillators with weak dissipation and noise: a pendulum which is acted on by a small noisy torque and opposed by a friction; and the noisy Duffing-van der Pol oscillator. But over a long time the weak dissipative and noise effects can be significant. This paper develops asymptotic techniques based on averaging and large deviations to study the effects of weak noise on the escape from the domain of attraction of stable equilibrium points and limit cycles in phase-space. 相似文献
999.
1000.
With the rapid development of ytterbium-doped fiber lasers, some obtrusive limitations on power scaling appeared. In order to avoid these problems, a scheme called tandem pumping is introduced into the fiber laser field. In this paper, the optical properties of an ytterbium-doped tandem-pumped fiber oscillator are presented. According to the oscillator profile, the proper gain fiber type and pump wavelength range are picked out, under the comprehensive consideration of laser conversion efficiency and beam quality. In addition, the photodarkening performances of tandem pumping lasers and conventional ones are compared based on practical application, with all possible impact parameters taken into account. Moreover, an all-fibered tandem-pumped oscillator centered at 1079.5 nm is built, in the way of clad pumping by a 1030-nm fiber laser. The laser power of the oscillator reaches 7 W, with an opto-optic efficiency of 82.4%. 相似文献