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1.
本文推演出密度矩阵元拓扑图示的最简约化方法.应用这方法,仅用n 1个拓扑图即可完备表征n阶非线性极化率, 与此同时还给出表达式中每一项的微观通道数.  相似文献   
2.
张培亮  郭奕理 《光学学报》1990,10(10):00-904
本文报道一种光电混合集成的有源双稳态器件,它仅由一只半导体激光器,两只PIN光电探测器及几只电子元器件构成.实验上得到了光学迟滞回线,显示了光开关、光存储、光脉冲整形等功能.文中简述了器件工作原理,光电混合集成制作工艺技术及性能指标.  相似文献   
3.
By utilizing the cross polarization modulation effect in semiconductor optical amplifier(SOA), the extinc tion ratio of cross gain modulation(XGM)wavelength conversion was enhanced, the pattern effect was significantly reduced,and the power penalty of wavelength conversion was reduced by 5 dB simultane-ously. Furthermore, by adjusting the settings of polarization controllers, both inverted and non-inverted wavelength conversion can be achieved right in the same wavelength converter.  相似文献   
4.
对基于半导体光放大器中交叉增益调制效应的波长转换后信号的啁啾特性进行了分析。研究了输入信号光和参考光和功率、波长、转换速率、信号光消光比以及半导体光放大器的偏置电流对转换后信号啁啾的影响。  相似文献   
5.
<正>A cost-effective method of multi-receiver optical orthogonal frequency-division multiplexing(OOFDM) system is proposed to reduce the requirement for the speed of the receiver and the size of fast Fourier transform(FFT).The sampling rate of analog-to-digital converters(ADCs) can be reduced to 1/N of the original signal bandwidth in an N-receiver system.Aided by signal predistortion at the transmitter, aliasing-free signal can be retrieved independently and directly at the low speed receivers.A back-to-back experimental result is given for a two-receiver system.The effect of the electrical filters added before the ADC is studied and the analysis for filters optimization is given.  相似文献   
6.
A method of multi-channel receiving for high bit rate heterodyne direct-detection optical orthogonal frequency-division-multiplexing (OOFDM) system is proposed to reduce the sampling rate demand of analog-to-digital converter (ADC). The sampling rate of ADCs can be reduced to 1/N that of the original signal bandwidth in an N-channel receiving system. Aided by a succeeding digital signal processing (DSP) at the receiver, aliasing free signal can be recovered. A back-to-back experimental result is given for a 4-channel system, based on which, a down conversion process for heterodyne can be reduced. The signal rebuilding algorithm is given and analyzed in its complexity and noise tolerance.  相似文献   
7.
A novel design of all-optical AND gate is proposed by using cross polarization modulation effect in a semiconductor optical amplifier. In this scheme, an additional continuous-wave beam is not required as that in traditional scheme. AND output is obtained on either of two input signal wavelengths. The AND scheme is numerically simulated and experimentally demonstrated at a bit rate of 10 Gb/s successfully.  相似文献   
8.
本文报道了在数十气压H_2中输出三级Stokes和六级anti-Stokes受激喇曼散射。着重研究了SRS能量转移中的受激喇曼过程(SRP)和四波参量过程(FWPP)。对前人报道得很少的高压H_2中的离轴Stokes圆环与轴上anti-Stokes圆斑进行了较系统的实验研究,并用非线性光学参量与非参量过程的有关理论对实验结果进行了讨论。  相似文献   
9.
我们着重研究了高压H2气Q(1)振动跃迁(4155cm-1)受激喇曼散射(SRS)中,参与非线性相互作用的几个参数(介质分子密度、跃迁线宽、泵浦光子密度以及非线性作用长度)对受激阈值与能量转换效率的影响。给出了自零到24atmH2气压范围内阈值随H2气压变化的实验结果,它与根据Dicke-Doppler展宽和碰撞展宽的联合效应的分析是一致的。讨论了由于受激喇曼过程(SRP)和四波混频参量过程(FWPP)共同影响下能量转换效率、压力-色散效应对高阶反斯托克斯的能量输出的重要影响。 关键词:  相似文献   
10.
We investigate the phase-preserving amplitude regenerative characteristics of the return-to-zero (RZ) differential- phase-shift-keying (DPSK) wavelength conversion based on four-wave m/xing (FWM) in a semiconductor optical amplifier (SOA). The Q-factor and the optical signal-to-noise ratio (OSNR) before and after conversion are experimentally obtained and analysed in different input noise power levels. In both the continuous-wave and synchronous clock pumping cases, we find that there is amplitude clamping in the FWM conversion due to the gain saturation of SOA, which can suppress the amplitude fluctuation of the converted DPSK signal before and after demodulation. We have achieved 2-dB Q penalty improvement in our experiment demonstration of lOGbit/s RZ-DPSK signal with OSNR lower than 19dB.  相似文献   
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