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1.
在未来的通信领域中,全光逻辑门是全光计算机和全光网络的基本单元。目前已经提出了很多实现全光逻辑门的结构和方法,但是全光逻辑的技术瓶颈也出现了,就是怎样能够将单个的全光逻辑门级联起来实现更复杂的逻辑关系。现存的全光逻辑门结构一般不具有很好的可以实现多级连接的级联性,而且现有的对于级联性的分析大都停留在理论层面,而没有与实际情况相结合,所以对于实际应用来说意义很小。提出了一种新型的基于高非线性Sagnac 干涉仪的超高速全光NOT 门,建立了它的数学模型,采用了与实际情况更加接近的高斯脉冲模拟输入光,并且在仿真结果的基础上分析了系统的级联性,对级联性的分析考虑了光纤损耗和走离效应的影响。得到的基本结论表明,所提出的全光逻辑门的结构能够在实际情况下保持良好的级联性。 相似文献
2.
Quantum gates are the important breakthrough in current computation and high-end data processing. Several quantum logic gates have been implemented in last few decades. In this paper, the idea of all-optical (photonic) Fredkin gate is proposed, which performs the swapping operation by a control signal. Corresponding simulation is also conducted with MATLAB, which shows the same result as the theoretical prediction. 相似文献
3.
Novel scheme for ultrafast all-optical XOR operation 总被引:1,自引:0,他引:1
Randel S. de Melo A.M. Petermann K. Marembert V. Schubert C. 《Lightwave Technology, Journal of》2004,22(12):2808-2815
A novel scheme for all-optical exclusive-OR (XOR) operating at 160 Gb/s is proposed and analyzed by means of numerical simulations. It consists of a Mach-Zehnder interferometer (MZI) where a semiconductor optical amplifier (SOA) is placed in each of its arms. This SOA-MZI setup is coupled to a delay interferometer, which acts as a signal regenerator. It is shown that error-free operation can be achieved at a data rate of 160 Gb/s, indicating that the proposed scheme is not limited by the SOA recovery time. 相似文献
4.
Header recognition and packet detection in all-optical networks using on/off optical ultrafast signalling at a fixed wavelength can be implemented by means of recently demonstrated optical sampling AND gates. A novel packet structure in which the header is spread in a TDM fashion over the optical packet allows the number of such AND gates to be minimised in the routing and receiving blocks thereby best exploiting the required electronics.<> 相似文献
5.
Wei Wang Poulsen H.N. Rau L. Hsu-Feng Chou Bowers J.E. Blumenthal D.J. 《Lightwave Technology, Journal of》2005,23(3):1105-1115
The Raman gain enhancement of a regenerative ultrafast all-optical cross-phase modulation (XPM) wavelength converter (WC) is quantitatively investigated and experimentally demonstrated to operate error free at 40 and 80 Gb/s. The regenerative nature of the converter is shown by experimentally demonstrating a negative 2-dB power penalty at 80 Gb/s. It is also shown that the Raman gain greatly enhances the wavelength conversion efficiency at 80 Gb/s by 21 dB at a Raman pump power of 600 mW using 1 km of highly nonlinear fiber. An analytical theory based on nonlinear phase-shift enhancement of the fiber-effective length is presented and shows the relationship between a nonlinear enhancement and Raman gain as a function of pump power and fiber design parameters. Measured parameters are used in the analytical model, and a good fit between experiment and theory is shown for two different types of fiber: one dispersion-shifted and one highly nonlinear fiber. The ultrafast response time of Raman gain makes this technique applicable to fiber-based ultrafast WCs. In addition, the applicability to other nonlinear fiber wavelength conversion techniques is discussed. 相似文献
6.
In all-optical gate switches that employ the cascade of second-harmonic generation and difference frequency mixing in quasi-phase-matched (QPM) lithium niobate (LN) devices, walkoff between the fundamental and second-harmonic pulses causes crosstalk of the switch. We numerically calculate the switching performance of QPM-LN waveguide devices with consideration for the crosstalk effect, and discuss the favorable choice of the nonlinear optical tensor element for the LN crystal. In the analyses, the device length is maximized for a given bit rate under the condition that the crosstalk is maintained below a critical level that is determined by the allowable power penalty for the switched signal. It is shown that the time offset between the gate and signal pulses can compensate for the walkoff, and can significantly improve the switching efficiency. In ultrafast operation beyond 1 Tbps, the use of the nonlinear optical tensor element d/sub 31/ is found to be favorable when compared to the use of the commonly used maximum tensor element d/sub 33/. 相似文献
7.
Yunfeng Zhou Jian Wu Jintong Lin 《Quantum Electronics, IEEE Journal of》2005,41(6):823-827
A novel scheme of all-optical XOR is proposed based on Sagnac interferometric structure. Using a semiconductor optical amplifier (SOA) as nonlinear medium, the operations of this scheme with 80 Gb/s return to zero pseudorandom bit sequence are simulated correctly with fairly high performance. Through numerical analysis, and by comparison of the performances between 40 and 80 Gb/s operation, parameters of the SOA and the signals are discussed, and this scheme is proved to exceed the speed limitation imposed by carrier lifetime of the SOA. This scheme is potentially capable of XOR operation speed to >100 Gb/s. 相似文献
8.
The authors propose a novel method of designing all-optical ultrafast gate switches that employ the cascade of the second harmonic generation and difference frequency mixing in quasi-phase matched LiNbO/sub 3/ devices. In this design method, the device length is maximized under the condition that crosstalk of the switch is maintained below a certain allowable value at a given bit rate. Following the design method, the authors find that the switching efficiency can significantly be enhanced by compensation for the walkoff between the fundamental and second harmonic pulses. 相似文献
9.
We investigated an all-optical logic AND operation at 10 Gb/s using nonlinear transmission of electroabsorption modulator pumped with two counterpropagating data streams. The transmitted pump itself was used as the output of the optical gate to obtain high extinction ratio, and high-output peak powers. The gate has been tested using 231 -1 long pseudorandom bit sequence. The logical output of the gate has an extinction ratio of more than 10 dB with good eye opening. Our measurements of the gate transmission window show that all-optical logic operation up to 100 Gb/s is feasible 相似文献
10.
L. Rau R. Doshi S. Rangarajan Yijen Chiu D.J. Blumenthal J.E. Bowers 《Photonics Technology Letters, IEEE》2003,15(4):560-562
Analog performance of an all-optical ultrafast wavelength converter is measured and reported for the first time. The wavelength-conversion process is based on nonlinear cross-phase modulation in an optical fiber combined with an optical filter to convert phase modulation to amplitude modulation. The spurious-free dynamic range (SFDR) of the converter is measured to be 82 dB/spl middot/Hz/sup 2/3/. We define a new metric called the SFDR power penalty, which measures the degradation in SFDR relative to baseline the back-to-back analog optical link. The SFDR power penalty was measured to be 5 dB/spl middot/Hz/sup 2/3/ and is shown to be a function of the input optical power. This metric is used to characterize the linear region of the optical wavelength converter. 相似文献
11.
12.
Demonstration of ultrafast all-optical wavelength conversion utilizing birefringence in semiconductor optical amplifiers 总被引:6,自引:0,他引:6
M.F.C. Stephens M. Asghari R.V. Penty I.H. White 《Photonics Technology Letters, IEEE》1997,9(4):449-451
High-extinction-ratio wavelength conversion has been demonstrated in a semiconductor optical amplifier using a mixture of cross-gain and cross-phase modulation in a polarization rotation technique. 40-ps-wide pulses at 1311 nm have been generated using 47-ps, 5.7-mW peak-power input pulses at 1300 nm. Excellent agreement with experiment has been obtained using a computer model. 相似文献
13.
Demonstration of the nonlinear fibre loop mirror as an ultrafast all-optical demultiplexer 总被引:3,自引:0,他引:3
The all fibre nonlinear optical loop mirror (NOLM) is used in the two wavelength version to show good contrast stable switching of selected pulses from a stream of short pulses. The polarisation properties of the device enable operation as a genuine four port demultiplexer.<> 相似文献
14.
Kung-Li Deng Koo Il Kang I. Glask P. Prucnal 《Photonics Technology Letters, IEEE》1997,9(11):1496-1498
Based on a passive k-stage feed-forward delay line structure, this letter presents a novel scheme which allows fast tuning among as many as 2/sup k//spl times/2/sup k/ ultrafast time-division multiplexed (TDM) channels in all-optical networks. At a lower speed, a simple selection rule is applied at the input and output of the structure to set the state of the delay. In the experimental demonstration, the delay line can be tuned to any of the 1024 50-Mb/s channels in a 50-Gb/s all-optical TDM network with a five-stage structure and two E/O modulators. The average reconfiguration time is about 20 ns. 相似文献
15.
16.
A novel photonic network, MATRIX (for multi-wavelength all-optical transparent information exchange), is proposed in this paper. The all-optical multihop network supports wavelength continuity and provides a very high network capacity. Spatial reuse of wavelengths as well as the multiplicity of fibers in optical fiber cables are exploited and enable the interconnection of N2 network nodes with merely N wavelengths. The node structure is simple since neither tunable devices nor wavelength converters are required. Packets are routed through the network by photonic fast packet switching as well as by wavelength and experience a maximum hop number of two. Multiple optical paths between any pair of nodes provide a good network survivability 相似文献
17.
We will review three recently-proposed high-speed, all-optical Exclusive OR (XOR) gates operating at 40 and 85?Gb/s, which were demonstrated using ultrafast nonlinear interferometers (UNIs) incorporating semiconductor optical amplifiers (SOAs). The first 40-Gb/s XOR gate was obtained using a dual UNI configuration. The second is a 40-Gb/s XOR gate without additional probe beam required, where the only inputs launched into the setup were data A and B. The XOR logic of data A and B is the sum of two components (A)B and(A)B , each of which was obtained from the output of UNI via cross-phase modulation (XPM) in SOAs. Furthermore, an 85-Gb/s XOR gate is, by far, the fastest XOR gate realized by SOAs, which was also demonstrated using a dual UNI structure. The operating speed of the XOR gate was enhanced by incorporating the recently proposed turbo-switch configuration. In addition, the SOA switching pulse energies of these XOR gates were lower than 100 fJ. 相似文献
18.
Optical gate switching for one signal beam using another control beam is presented in a Fabry-Perot semiconductor laser amplifier. High-speed switching, where the signal output is on without the control beam and off with it, is demonstrated employing modulation of an 800 Mbit/s pulse pattern. 相似文献
19.
Parameswaran K.R. Fujimura M. Chou M.H. Fejer M.M. 《Photonics Technology Letters, IEEE》2000,12(6):654-656
We present an all-optical gate implemented in periodically poled lithium niobate (PPLN) (LiNbO3). Efficient mixing is achieved by using a phase-matched guided-wave interaction. A control wave at 1.537 μm is used to gate a signal at 1.552 μm, where a control power of 185 mW is sufficient to achieve 96% depletion of a low-power signal. A simple switch configuration is described whereby high-contrast low-power all-optical switching can be performed 相似文献
20.
为了能够同时对多波长信号进行加密操作,两路相干光信号进行直接干涉前,通过对其中一路光信号进行Pi相移,Pi相移后两路信号的干涉结果即为两信号异或(XOR)逻辑结果。基于此原理,提出一种应用于波分复用(WDM)系统,能够同时对多波长复用信号进行XOR加密的方案。方案通过直接电光调制得到不同波长相干光信号与光密钥,且通过相移单元同时对多波长光密钥进行Pi相移,相移后相同波长的光密钥与光信号的耦合干涉输出便是对光信号的XOR加密结果,并输出多波长复用的加密信号。通过8×10Gbit/ps的WDM信号的加密仿真得到该方案加密输出误码率(EBR)为0,Q因子为164,证实了方案的可行性与有效性。分析了脉冲占空比对加密输出信号Q因子的影响。通过理论与仿真分析了输入归零码信号占空比对加密信号质量的影响得出,当信号占空比小于0.43时,加密输出信号Q因子能够稳定在164左右。 相似文献