Interferometric FBG Interrogation for Characterization and Sensing - INVITED

Results on grating characterization and sensing of temperature, strain, and load induced birefringence with high spatial resolution in silica and plastic optical fibers using optical low coherence reflectometry are reported

Annealing of UV Ar+ and ArF excimer laser fabricated Bragg gratings: SMF-28e fiber

Fiber Bragg gratings fabricated in pristine SMF-28e fibers using pulsed ArF-excimer and cw 244-nm Ar+ laser were annealed using tempering rates from 0.0038 to 0.25 K/s. Demarcation energy mapping allowed for the determination of the frequency factors and the master curves for the SMF-28e fiber under different irradiation conditions. A Gaussian decomposition of the underlying energy distribution revealed several individual activation energy distributions characteristic for the fiber with peak energies and widths that were independent of the laser used. From a fit of the integrated Gaussian distributions to the master curves the relative contributions of the individual energy distributions that appeared in both irradiation conditions were calculated. The difference in the activation energy spectra obtained from the two laser irradiations are explained by the relative contributions of the individual distributions that differ. Using the analytical description of the master curve, thermal stability maps were obtained

Workshop: Towards high capacity fibers for space and mode division multiplexed transmission

The demand for capacity is growing exponentially with about 40-60% per year passing the installed network capacity. For the last two decades the transmission capacity per fiber has increased by more than three orders of magnitude: Single channel (wavelength and polarization) electronically time-division multiplexed (ETDM) transmission showed a growth of one order of magnitude over the last two decades reaching 100 Gb/s; and multi-channel wavelength division multiplexing (WDM) increased the transmission capacity for a decade with a growth rate of 78% over the last decade, reaching more than 10 Tb/s. However, WDM has been leveling off since the turn of the millennium due to the full exploitation of the EDFA gain bandwidth and the lack of active ions in silica able to cover the full fiber bandwidth. Research in the last years has focused on coherent detection combined with powerful digital signal processing thus upgrading the installed fiber network to increase the available capacity per fiber. Although 100 Tb/s have recently been demonstrated, additional channels dimensions (on top of wavelength and polarization) will be required to avoid the capacity crunch and to keep up with the increase of capacity demand in the decades to come. As breakthrough technologies emerge space division (SDM) and/or mode division multiplexing (MDM) with the development of novel fibers, novel multiplexing and de-multiplexing components, and novel signal processing techniques. In this workshop, we will review and discuss some of the emerging technological options and consider their potential: Development of different types of multi-core fibers, allowing for coupling or suppressing the coupling between cores; few-mode and multimode fibers; multiplexing and de-multiplexing of optical signals with these novel fibers; signal processing schemes; and the combination of different multiplexing technologies for transmission

Stress changes in H2-loaded SMF optical fibers induced by cw-Ar+ 244 nm irradiation

Bragg gratings were inscribed in H2-loaded SMF-28e optical fibers and measured for axial stress changes for various exposure doses. Mean refractive index changes as high as 7.5 × 10-3 were observed under cw-244 nm irradiation of 143 W/cm2. Bragg grating reflectivity >99% was achieved for 0.7 mm long (1/e2) gratings. Axial stress measurements realized before and after UV exposure of the fibers, show two competing dose-dependent photosensitivity mechanisms: Negative stress changes at the early stages of exposure and positive stress changes for high exposures

Workshop: Next-Generation Fibers for High Capacity Transmission—Radical Solutions

Driven by the exponentially growing demand for capacity, it is already apparent that the next generation of telecommunication networks will be radically different from previous implementations; coherent detection along with powerful digital signal processing will be deployed to maximize the available capacity of each fiber strand within the network. However, applied in isolation these techniques will only delay the inevitable "capacity crunch" by a few years and without radical innovation in the basic internet infrastructure future internet growth will be severely constrained. Research on new transmission fibers and amplifiers is therefore now urgently required. In this workshop we will review and discuss some of the potential technological options and consider their potential and viability of these from a capacity, power handling and energy sustainability perspective. Speakers