Design and fabrication of an intrinsically gain flattened Erbium doped fiber amplifier

Abstract

International audienceWe report design and subsequent fabrication of an intrinsically gain flattened Erbium doped fiber amplifier (EDFA) based on a highly asymmetrical and concentric dual-core fiber, inner core of which was only partially doped. Phase-resonant optical coupling between the two cores was so tailored through optimization of its refractive index proile parameters that the longer wavelengths within the C-band experience relatively higher amplification compared to the shorter wavelengths thereby reducing the difference in the well-known tilt in the gains between the shorter and longer wavelength regions. The fabricated EDFA exhibited a median gain > 28 dB (gain excursion below ±2.2 dB within the C-band) when 16 simultaneous standard signal channels were launched by keeping the I/P level for each at -20 dBm/channel. Such EDFAs should be attractive for deployment in metro networks, where economics is a premium, because it would cut down the cost on gain flattening filter head

Application Specific Optical Fibers

“…Use of an intrinsically gain flattened EDFA would cut down the cost on the GEF head. This motivated some investigators [e.g., Nagaraju et al, 2009] to investigate design of an inherently gain flattened EDFA by exploiting a wavelength filtering mechanism inherent in a co-axial dual-core fiber design scheme. An example of the design of such a gain-flattened EDFA is shown in Fig.…”

“…6, which was based on a highly asymmetric dual-core concentric fiber design (see Fig. 6), whose inner core was only partially doped with erbium [Nagaraju et al, 2009]. Refractive index profile (RIP) of the designed inherently gain flattened EDFA and the RIP of the corresponding fabricated preform are shown in Fig.…”

Design and fabrication of an asymmetric twin-core fiber directional coupler for gain-flattened EDFA

“…Such inherently gain equalized EDFAs are attractive for metro-centric networks because low cost components and less number of components (to cut down the network maintenance cost) have been a major driver in a metro network design. Exploitation of a wavelength filtering mechanism inherent in a co-axial dual-core fiber design scheme to realize a gain flattened EDFA was reported by us earlier [1]. Laming et al were possibly first to propose in 1993 a scheme for gain equalization utilizing a twin core amplifier [2].…”

Impact of Elliptical Holes Filled with Ethanol on Confinement Loss and Dispersion in Photonic Crystal Fibers

“…We are interested to fibers formed by a doped silica core which present a difference n between the core and the cladding [3][4]. This photonic cladding it is composed of holes filled with ethanol in the silica.…”