共查询到20条相似文献,搜索用时 203 毫秒
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在四能级钕玻璃波导放大器物理模型的基础上,用重叠积分法研究了以802nm泵浦光放大1060nm信号的掺钕磷酸盐波导放大器的速率-传输方程。通过数值模拟,获得了增益特性和波导掺杂浓度、泵浦功率和波导长度的曲线关系。 相似文献
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提出了一种新型微腔半导体光放大器结构,该半导体放大器在普通行波光放大器的波导结构上引入了上下布拉格反射镜,并在波导前后两侧的上端面上分别刻蚀出入射和出射光学窗口,其上蒸镀增透膜层.信号光以一定的倾角斜入射到波导中,以之字型路线沿波导传播.提出了一个完整的、考虑了微腔特性的稳态模型,系统模拟了微腔半导体光放大器的特性.结果表明该微腔半导体光放大器的光纤到光纤增益可达40dB,而噪声指数只有3.5dB. 相似文献
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Pleumeekers J.L. Dupertuis M.-A. Hessler T. Selbmann P.E. Haacke S. Deveaud B. 《Quantum Electronics, IEEE Journal of》1998,34(5):879-886
The longitudinal spatial hole burning (LSHB) in gain-clamped semiconductor optical amplifiers (GCSOAs) is investigated by means of a numerical model, which is based on position-dependent rate equations for the carrier density and the propagation equations for the optical power. The simulation results show that the carrier densities are nonuniformly distributed within the active layer of GCSOAs. The nonuniformity can be large, especially for high currents and optical signal powers near the saturation. It is found that the LSHB induces a gain nonlinearity, which causes interchannel cross talk when GCSOAs are used in wavelength division multiplexing (WDM) applications. In order to reduce this gain nonlinearity, two methods are analyzed: the use of low resistivity devices and the use of unbalanced Bragg mirror reflectivities 相似文献
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一种表面等离子体激元定向耦合器的传输特性 总被引:3,自引:0,他引:3
利用三维全矢量时域有限差分法(FDTD)数值模拟了一种波导间隔金属条高度小于金属层厚度的表面等离子体激元(SPP)定向耦合器,并分析了其在基模传输时的模式场分布和能流密度分布,讨论了耦合长度、最大转移功率与间隔金属条高度的变化关系。结果表明,波导内沿纵向的能流密度在靠近间隔金属条部分的强度更大,有助于提高波导间耦合效率,并且当减小间隔金属条的高度时可以有效缩短定向耦合器耦合长度。这种亚波长定向耦合器结构可以应用在基于表面等离子体激元的集成光路中。 相似文献
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Mehuys D. Welch D.F. Parke R. Waarts R.G. Hardy A. Scifres D. 《Electronics letters》1991,27(6):492-494
A novel monolithically integrated master oscillator power amplifier with a distributed amplifier/grating output coupler is demonstrated which emits 370 mW in a single-frequency diffraction-limited beam without any form of active phase control. The distributed amplifier/grating output coupler results in a guided mode power that saturates along the direction of propagation, providing a uniform carrier density to preserve the flatness of the radiated phase front.<> 相似文献
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The spatio-temporal dynamics of broad-area semiconductor lasers is studied theoretically by numerically solving space-dependent coupled partial differential equations for the (complex) optical fields, the interband polarization and the density of charge carriers. The formation and longitudinal propagation of unstable transverse optical filamentary structures is analyzed in a model configuration for typical double-heterostructure broad-area lasers. Spectral and spatial holeburning in the carrier distributions is observed as a consequence of selective density depletion by the transverse laser modes. The transverse holeburning leads to complex spatio-temporal patterns 相似文献
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Calero J. Sou-Pan Wu Pope C. Shun Lien Chuang Murtha J.P. 《Lightwave Technology, Journal of》1994,12(6):1081-1091
Theoretical and experimental results on birefringent optical fibers embedded in concrete are presented and discussed. We study the effect of strain on the propagation of light in birefringent fibers embedded in a host material loaded under uniform compression. Both longitudinal and transverse deformations are considered in the analysis since the fiber is embedded along a direction perpendicular to the strain load. The effects of the strain on the birefringence of the fiber and the rotation of the optical axis are studied. The theoretical model is used to determine the best polarimetric system configuration to detect strain. Our experimental work was performed by embedding optical fibers in standard concrete cylinders, attaching resistive electric strain gauges on the surface, and testing the specimens under uniform compressive stress. Optical transmission data from the fiber and readings from the electric strain gauges were simultaneously recorded 相似文献
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Braagaard C. Mikkelsen B. Durhuus T. Stubkjaer K.E. 《Lightwave Technology, Journal of》1994,12(6):943-951
In this paper, a novel and efficient way to model the dynamic field in optical DBR-type semiconductor devices is presented. The model accounts for the longitudinal carrier, photon, and refractive index distribution. Furthermore, the model handles both active and passive sections that may include gratings. Thus, simulations of components containing, e.g., gain sections, absorptive sections, phase sections, and gratings, placed arbitrarily along the longitudinal direction of the cavity, are possible. Here, the model has been used for studying the DBR laser as a wavelength converter. Particularly, to improve the performance of the DBT converter, the influence of system and device parameters will be discussed. Calculations show that ultrafast wavelength conversion with rise and fall times less than 50 ps can be obtained. Also, a regenerative effect simultaneous with the wavelength conversion is expected, e.g., improvements in the extinction ratio of the signal of more than 6 dB is predicted for correct design and operation of the component 相似文献
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A numerical study of erbium doped active LiNbO3waveguides by the beam propagation method 总被引:1,自引:0,他引:1
A numerical investigation of active waveguides realized on lithium niobate crystals using erbium as active element is presented. A software package is implemented to simulate the propagation of electromagnetic waves in graded-index active waveguides using an active vectorial beam propagation method (ABPM), which enables to calculate the optical field evolution along the propagation axis. A comparative study of the optical signal gain evolution as function of erbium concentration profiles obtained by various doping methods is presented. The optimal doping method, leading to the maximum gain, is determined 相似文献
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The transfer matrix method (TMM) has been applied to analyze the gain and saturation characteristics of semiconductor laser optical amplifiers. This method approximates the amplifier cavity by dividing it into M discrete subsections, and TMM has been applied to analyze the stepwise longitudinal field distribution at each subsection along the amplifier cavity. By incorporating also the carrier rate equations into the analysis, it has been shown that the approximation can accurately describe the carrier density and longitudinal field distribution along the amplifier cavity if M is sufficiently large (i.e., the size of each subsection is about an order of magnitude of one wavelength of the input signal). By assuming that the amplifier is biased below oscillation threshold such that the contribution of spontaneous emissions to the gain characteristics can be neglected, we have shown that our proposed method yields a fast and efficient algorithm in analyzing the gain and saturation characteristics of laser amplifiers. We have compared the results produced by our method to those analyzed using the average photon density (AVPD) approximation technique, as well as to experimental results on a 1.5-μm buried heterostructure semiconductor laser amplifier 相似文献
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The effects of the onset of lasing on the I-V characteristics, the impedance characteristics and the light modulation characteristics of laser diodes have been discussed by introducing the rate equations which involve carrier diffusion process in the active layer interacting with the radiation field intensity. The static I-V characteristics exhibit a kink at lasing threshold current, reflecting the decrease of effective lifetime of carriers. Effective carrier lifetimes decrease with increasing light intensity, which results in a steep attenuation of injected carrier density in the active region. The impedance and light modulation characteristics are obtained in the small signal approximation. The small signal light modulation characteristics depend strongly on whether the laser diode is excited by the constant current modulation or the constant voltage modulation. The impedance is changed drastically by the onset of lasing and exhibits a resonance which coincides exactly with the optical modulation resonance frequency. 相似文献