[Show abstract][Hide abstract] ABSTRACT: We propose and experimentally demonstrate an all-optical Manchester NOT gate. A logic NOT signal is realized for a 10 Gb/s Manchester encoded signal, based on cross-gain modulation (XGM) in a reflective semiconductor optical amplifier (RSOA).
[Show abstract][Hide abstract] ABSTRACT: Simultaneous all-optical frequency down-conversion technique based on cross-phase modulation in a high nonlinearity dispersion-shifted fiber is proposed and verified by simulation, and its application to a wavelength-division-multiplexing (WDM) radio over fiber (ROF) is proposed. Error-free simultaneous all-optical frequency down-conversion of the 16 WDM ROF upstream channels is achieved. The simulated results show the performance of WDM signals is in good accordance with a single signal without any interference, and the power difference of two beat frequencies of the down-conversion signal is independent of the optical local oscillator power. The wavelength span of larger than 20 nm for down-conversion signal can be obtained.
[Show abstract][Hide abstract] ABSTRACT: All-optical flexible 20-Gb/s logic and gate based on cascaded sum- and difference-frequency generation in a periodically poled lithium niobate waveguide is proposed and experimentally demonstrated. The theoretical analyses further indicate that 40-, 80-, and 160-Gb/s ultrahigh-speed logic and operations can potentially be performed. Moreover, it is expected that the and output can be tuned in a wide wavelength range (67 nm) with slight fluctuation of the Q-factor and extinction ratio.
[Show abstract][Hide abstract] ABSTRACT: Birefringence in semiconductor optical amplifier (SOA) has begun to receive increasing attentions in recent years, in this paper we investigate the effect of birefringence on spectral broadening of ultrashort optical pulse, based on Jones Matrix method, Fourier transform method and a multi-section model, which takes into account the polarization dependency of phase modulation. The time-dependent carrier distribution, pulse amplification process and pulse spectrum evolution along SOA is simulated. It is found that a considerable part of spectral broadening comes from birefringence, this kind of additional spectral broadening depends on bias current, optical power and pulse shape of input pulse.
Full-text · Article · Aug 2003 · Proceedings of SPIE - The International Society for Optical Engineering
[Show abstract][Hide abstract] ABSTRACT: This paper aims at numerically simulating gain recovery enhancement effect in semiconductor optical amplifiers (SOAs) when a CW pump light is applied. The effective carrier lifetime reduction behaviors are simulated for different CW wavelengths. Gain saturation behaviors at the signal wavelength as well as gain and phase-shift dynamics introduced by short pulse amplification in presence of the CW pump light are also simulated for different CW wavelengths and powers. The results confirms the feasibility of enhancing the recovery rate of SOA by a CW pump light near the material transparency wavelength.
Preview · Article · Dec 2002 · Proceedings of SPIE - The International Society for Optical Engineering
[Show abstract][Hide abstract] ABSTRACT: The fiber-optic Mach-Zehnder (M-Z) interferometer can be used as wavelength-multiplexers and demultiplexers. The ΔL and ΔΦ directly influence the properties of M-Z. Through lengthening the ΔL, M-Z can demultiplex many more wavelengths. But the longer ΔL is, the more seriously the temperature will influence M-Z. We explored a method to solve this problem, making M-Z work stably. The wavelength spacing is 0.8 nm, and the extinction ratio is high.
[Show abstract][Hide abstract] ABSTRACT: A novel scheme for XGM wavelength conversion based on
single-port-coupled SOA has been achieved with improved extinction ratio
performance. In wavelength upconversion between 1549.8 nm and 1562.6 nm
at 2.5 Gbit/s, the output extinction ratio can be higher than 15 dB.
Theoretical calculation shows that its extinction ratio and input
dynamic range are better than that in conventional schemes based on
identical long and double long, double-port-coupled SOA
[Show abstract][Hide abstract] ABSTRACT: A novel XGM wavelength conversion scheme exploiting semiconductor
laser amplifier in a loop mirror (SLAOLM) has been demonstrated. Results
showed that this scheme is helpful for extinction ratio and noise
performance improvement simultaneously, due to the coexistence of gain
saturation and phase modulation effect
[Show abstract][Hide abstract] ABSTRACT: Summary form only given. The XGM wavelength conversions reported before are all based on gain saturation effect in which the phase of the converted signal is inverted to the input signal, that will increase the complexity in signal processing and the system cost. Furthermore, due to the inverting operation of the converter, the converted pulses are blue shifted on the leading edge while red shifted on the trailing edge. This leads to a pronounced pulse broadening when transmitted over standard nondispersion shifted fiber. In-phase wavelength conversion based on cross-gain modulation (XGM) in SOA, to our knowledge, is the first time to be demonstrated by adjusting structure parameters and selecting appropriate bias current of the SOA
No preview · Article · Jan 2000 · Filtration Industry Analyst