Four-wave Mixing In Dispersion-shifted Fiber Research Articles

Fiber-based narrow-band single-photon source with high heralding efficiency

According to the correlated photon pairs produced by spontaneous four-wave mixing in dispersion-shifted fiber, we present a telecom-band single-photon source by using mode-locked laser. Single-photons with a -3 dB bandwidth of 1.1 nm are heralded with more than 50% probability. The measured second-order correlation g(2)(0) is equal to 0.090.01. Our source is well suit for quantum communication systems.

Experimental Investigation of Quality of Service in an IP All-Optical Network Adopting Wavelength Conversion

We experimentally show how the virtual private large-area network service (VPLS) technique, a layer 2 service, can improve optical network performance in terms of quality of service (QoS), and how a VPLS network behaves when it adopts all-optical wavelength conversion (AOWC), a new optical process that will be introduced in future optical networks. The advantages of VPLS are based on the capability to generate logical reliable paths in each wavelength channel, permitting suitable partitioning of the bandwidth according to the user requirements. In particular, we show the advantages of VPLS in access networks based on passive optical networks, and we test QoS properties of VPLS paths when an AOWC process occurs both in the core and in the access networks. The experimental investigation is carried out in a wide-area, all-optical gigabit Ethernet testbed with an access section based on an Ethernet passive optical network. As far as the core segment is concerned, we chose a high-efficiency AOWC process based on four-wave mixing in dispersion-shifted fiber; conversely in the access segment we chose a cheaper AOWC process based on cross gain modulation in a semiconductor optical amplifier. The reported results show that gigabit Ethernet transmission, with the relative layer 2 techniques, is also well suitable for wide-area WDM architectures, and in particular it is able to guarantee end-to-end QoS for huge bandwidth services such as high-definition TV and also in the case of congestion, restoration, and wavelength conversion processes.

High-brightness, low-noise, all-fiber photon pair source

We demonstrate an all-fiber photon pair source for the critical telecom C-band. We achieve high pair generation rates in excess of 10 MHz while maintaining coincidence-to-accidental ratios (CARs) greater than 100. This is one of the brightest and lowest-noise photon pair sources ever demonstrated. We achieve the high pair rate through CW-pumped spontaneous four-wave mixing in dispersion-shifted fiber. We achieve the high CAR by cooling the fiber to 4 K to suppress the Raman generation and detecting the photons with low jitter and low dark count superconducting single-photon detectors.

All-Optical Multicast Switch Employing Raman-Assisted FWM in Dispersion-Shifted Fiber

We demonstrate an all-optical multicast switch with the capability to select five reconfigurable channel groups with six output multicast channels using three control wavelengths at 10 Gb/s using Raman-assisted four-wave mixing in dispersion-shifted fiber. All the output channels comply with the 100 GHz (i.e., 0.8 nm) spaced International Telecommunication Union (ITU) grid.

Detailed numerical analysis of a four-wave mixing in dispersion-shifted fiber based all-optical wavelength converter of 10 Gb/s single sideband optical signal

We analyze the Q factor and the conversion efficiency of all-optical wavelength converter based on four-wave mixing in dispersion-shifted fibers at 10 Gb/s employing single sideband signal. We find that the Q factor of the converted signal is always higher for upper-single sideband signal with upward conversion in wavelength and for lower-single sideband signal with downward conversion. The four-wave mixing efficiency is higher when the pump wavelength is deviated positively relative to the fiber zero-dispersion wavelength. The used of low dispersion slope allows broad bandwidth and broad dynamic range of pump wavelength. From this study we depict the working characteristics of an all-optical wavelength converter for upper and lower single side band signals, providing guidelines to the utilization of these very promising technologies in the implementation of the future high bit rate all-optical networks.

The influence of pump wavelength on the performance of wavelength conversion of 10-Gb/s single-side-band optical signal based on four-wave mixing in dispersion-shifted fiber

We experimentally study the influence of the pump wavelength on wavelength-conversion performance based on the four-wave mixing effect in dispersion-shifted fiber of 10-Gb/s single-side-band optical signals. In our experiment more than 10 nm for a 3-dB Q factor penalty was achieved for this configuration. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 493–495, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21026

Polarization-Insensitive All-Optical Wavelength Conversion Using Dispersion-Shifted Fiber With a Fiber Bragg Grating and a Faraday Rotator Mirror

We demonstrate a simple technique for polarization-insensitive all-optical wavelength conversion based on four-wave mixing in dispersion-shifted fiber (DSF) with a fiber Bragg grating and a Faraday rotator mirror. The experimental residual polarization sensitivity is reduced from more than 22-2 dB with 4 km of DSF, and the power penalty incurred in wavelength conversion for 10-Gb/s nonreturn-to-zero data is less than 1 dB for a 20-nm conversion distance. Theoretically, this technique will have negligible polarization sensitivity when the propagation loss of the pump through the DSF approaches zero.

Distributed measurements of chromatic dispersion and nonlinear coefficient in low-PMD dispersion-shifted fibers

We report on the investigation of distributed chromatic dispersion (CD) and distributed nonlinear coefficient (NLC) measurements based on phase mismatched four-wave mixing in dispersion-shifted fibers (DSFs). Experimental results of the distributed CD maps for low polarization-mode dispersion (PMD) DSF fibers are discussed. We also report how nonnegligible values of PMD can adversely affect the distributed CD measurements. A new method to measure the distributed NLC map in low-PMD DSF fibers is also proposed and demonstrated experimentally.

Influence of phase mismatch on a spectral inverter based on four-wave mixing in dispersion-shifted fiber at 10 Gb/s

We investigate the influence of phase mismatch on the performance of a spectral inverter based on four-wave mixing in a commercial dispersion-shifted fiber. The inverter operates at 10 Gb/s. When the pump wave is tuned /spl plusmn/0.3 mn around the zero-dispersion wavelength of the fiber, the power penalty at 10/sup -9/ bit-error rate remains within the range of 1-2 dB, although the conjugate power is reduced considerably by almost 6 dB. A numerical calculation of the inverter's efficiency is also presented, which takes into account longitudinal variation of the zero-dispersion wavelength along the fiber.