Wideband Erbium-doped Fiber Amplifier Research Articles

An efficient wideband hafnia-bismuth erbium co-doped fiber amplifier with flat-gain over 80 nm wavelength span

Abstract A new wideband erbium doped fiber amplifier (EDFA) is proposed and demonstrated, utilizing a newly fabricated hafnia-bismuth erbium co-doped fiber (HB-EDF) as a gain medium. The proposed amplifier is tested in both double-pass series and parallel configurations, using 22 cm and 150 cm long HB-EDFs to realize amplification in C and L-band wavelength region, respectively. Both series and parallel configurations obtained a wideband operation at wavelength region from 1520 to 1610 nm. At input signal power of −10 dBm, the parallel HB-EDFA achieved a flat gain of 12.1 dB with a gain ripple of less than 2 dB, along the wavelength region of 80 nm from 1525 to 1605 nm. Within the flat gain region, the noise figure was less than 11.8 dB. Overall, the parallel HB-EDFA has a better performance than the series HB-EDFA.

New topology of wide band EDFA using split band double pass amplification

ABSTRACTA novel design of high and broad gain that covers C and L bands is demonstrated experimentally. The techniques, used in this paper, combine two double pass with split band structure. The signals travel in separate paths after being splitted using a coupler band splitter. The topology of this new configuration uses this technique to broaden the gain at its maximum range of amplification. The presented paper is to study the performance of the augmented gain of the EDFA configuration using what it can be called double pass wide band amplification. The results show a broadening range of 80 nm between 1520 nm and 1600 nm in the C and L band and high gain of 45 dB for the range 1525 nm and 1580 nm and lower gain for the range 1580 nm and 1600 nm. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2093–2096, 2016

Flat-gain wide-band erbium doped fiber amplifier with hybrid gain medium

A new erbium-doped fiber amplifier (EDFA) is demonstrated using a combination of zirconia-based erbium-doped fiber (Zr-EDF) and silica-based Erbium-doped fiber (Si-EDF) as the gain medium. The EDFA comprises a 2 m long Zr-EDF and 9 m long Si-EDF optimized for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fiber Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.

Study of ASE noise power, noise figure and quantum conversion efficiency for wide-band EDFA

High gain and low noise figure (NF) are desired features of any erbium doped fiber amplifier (EDFA) based configuration. In this paper, the effect of wavelength and bandwidth on amplified spontaneous emission noise power (PASE) for wide-band erbium doped fiber amplifier (W-EDFA) has been discussed in particular. We present the noise figure (NF) as a function of inversion parameter (nsp) for different wavelengths. Finally we presented quantum conversion efficiency (QCE) varying with different pump power and signal power at 980 and 1480nm pumps. We observe that; amplified spontaneous emission noise power (PASE) increases exponentially with the inversion parameter (nsp) and the effect of change wavelengths on a noise figure are a non-significant. The 980nm pumped device offer significant advantages in terms of a much better quantum conversion efficiency performance than 1480nm pumped.

Flat-gain wide-band erbium doped fiber amplifier by combining two difference doped fibers

A new erbium-doped fibre amplifier (EDFA) is demonstrated using a combination of newly developed Erbium Zirconia co-doped fiber (Zr-EDF) and the commercial silica-based Erbium-doped fiber (Si-EDF) as the gain medium. Both fibers have a very high concentration of erbium ion. A compact amplifier operating in C-band region is firstly reported using a double-pass configuration. It is shown that average gains of the proposed Zr-EDF amplifier are obtained at approximately 18 dB with a gain variation of ±2 dB within C-band region. A flat-gain and wide band operation is achieved by configuring the amplifier in two stages comprising a 2 m long Zr-EDF and 9 m long Si-EDF optimised for C- and L-band operations, respectively, in a double-pass parallel configuration. A chirp fibre Bragg grating (CFBG) is used in both stages to ensure double propagation of the signal and thus to increase the attainable gain in both C- and L-band regions. At an input signal power of 0 dBm, a flat gain of 15 dB is achieved with a gain variation of less than 0.5 dB within a wide wavelength range from 1530 to 1605 nm. The corresponding noise figure varies from 6.2 to 10.8 dB within this wavelength region.

Modeling of Wide-Band Optical Signal Amplification in an EDFA Network Using Tunable Tap

Optical amplification in C and L band region with wave division multiplexing can provide over 160 channels. The paper provides simulation studies of such a wideband erbium doped fiber amplifier which utilizes a tunable tap at the TLS source end. This isolates and provides two parallel channels for simultaneous amplification in both C and L band. Such a configuration has shown to provide a gain well over 20dB from 1525-1615nm bandwidth with average noise figure of 10dB (approx.). Gain saturation effects beyond -20dBm/channel signal level and, gain spectra at different pump powers and amplifier lengths have also been studied. Full Text: PDF References Robert E. Tench, Proc. IEEE Elecronic Componenets and Technology Conference. 9, (1999). J. F. Massicott, R. Wyatt, and B. J. Ainslie, "Low noise operation of Er 3+ doped silica fibre amplifier around 1.6 ?m", Electron. Lett. 28, 1924 (1992). CrossRef Y. Sun, A. Srivastava, J.Zhou, and J. Sulhoff, "Optical fiber amplifiers for WDM optical networks", Bell Labs Technical Journal. 4, (1999) CrossRef H. Ono, M. Yamada and Y. Ohishi, "Gain-flattened Er/sup 3+/-doped fiber amplifier for a WDM signal in the 1.57-1.60-?m wavelength region", IEEE Photon. Technol. Lett. 9, (1997). CrossRef C. Jiang, W. Hu, Q. Zeng and S. Xiao, "High detectivity GaInAs-InP quantum-well infrared photodetectors grown on Si substrates", IEEE Photon. Technol. Lett. 14, 290 (2002). CrossRef M. A. Mahdi, F. R. M. Adikan, P. Poopalan, S. Selvakennedy, W. Y. Chan, and H. Ahmad, "Long-wavelength EDFA gain enhancement through 1550 nm band signal injection", Opt. Commnun.175, 296 (2000). CrossRef H. Chen, M. Leblanc and G.W. Schinn, "Gain enhanced L-band optical fiber amplifiers and tunable fiber lasers with erbium-doped fibers", Opt. Comm. 216, 119 (2003). CrossRef M. A. Mahdi and H. Ahmad, "Gain enhanced L-band Er/sup 3+/-doped fiber amplifier utilizing unwanted backward ASE", IEEE Photon. Technol. Lett. 13, 1067 (2001). CrossRef S. W. Harun, N. Tamchek, P. Poopalan and H. Ahmad, "Gain clamping in two-stage L-band EDFA using a broadband FBG", IEEE Photon. Technol. Lett. 16, 422 (2004). CrossRef T. Sakamoto. "Wide wavelength band (1535?1560 nm and 1574?1600 nm), 28 × 10 Gbit/s WDM transmission over 320 km dispersion-shifted fibre", Electron. Lett.34, 392 (1998). CrossRef Y. Sun et al., "80 nm ultra-wideband erbium-doped silica fibre amplifier", Electron. Lett. 33,1965 (1997). CrossRef T. Kasamatsu, Y. Tano and T. Ono, 13, 31 (2001). S. K. Liaw and Y. K. Chen, "Self-phase modulation coefficient of multiple-quantum-well optical amplifiers", IEEE Photon. Tech. Lett. 8, 876 (1996). CrossRef A. Srivastava and Y. Sun, Optical Fiber Telecommunications, I. P. Kaminov and T. Li, Eds. (San Diego, CA: Academic 2002, vol. VI A). R. Anthony and S.N. Biswas, "Temperature Dependent Gain Analysis of a Cascaded C-Band EDFA DWDM Network", Elseviers Procedia Technol. 4, 92 (2012). CrossRef G. Luo, J. L. Zyskind, I. A. Nagel, and M. A. Ali, "Experimental and theoretical analysis of relaxation-oscillations and spectral hole burning effects in all-optical gain-clamped EDFA's for WDM networks", IEEE J. Lightwave Technol. 16, 527 (1998). CrossRef I.K. Bu Sohn and J.W. Song, "Gain flattened and improved double-pass two-stage EDFA using microbending long-period fiber gratings", Optical Communications. 236, 141 (2004). CrossRef R. Singh, Sunanda and E.K. Sharma, "Gain flattening by long period gratings in erbium doped fibers", Optical Communications. 240, 123 (2004). CrossRef

OPTICAL AMPLIFIER WITH FLAT-GAIN AND WIDEBAND OPERATION UTILIZING HIGHLY CONCENTRATED ERBIUM-DOPED FIBERS

In this paper, we proposed a flat-gain and wide-band erbium doped fiber amplifier (EDFA) using two chirped fiber Bragg grating (CFBG) in serial configuration for double-pass operation. The amplifier consists of two sections of Erbium-doped fiber (EDF) operating in C-band and L-band respectively. A CFBG is used in each section to reflect the amplified signal back to the active area so that the overall gain spectrum can be enhanced and flattened. It is also observed that the gain of the amplifier produces a relatively higher gain with the Bismuth-based EDF (Bi-EDF) in the first stage compared to that of silica-based EDF (Si-EDF), especially in a longer wavelength region. The small signal gain of more than 19 dB is obtained within a wavelength region from 1545 to 1605 nm by the use of Bi-EDF with a small noise figure penalty. With a Si-EDF, the flat gain spectrum is observed within a wavelength region ranging from 1535 nm to 1605 nm with a gain variation of less than 2 dB at input signal of 0 dBm. This shows that the proposed serial double-pass amplifier may find its broad applications in wavelength division multiplexing long-haul systems as well as local optical networks.

Wideband and compact erbium-doped fiber amplifier using parallel double-pass configuration

In this article, a wide-band erbium doped fiber amplifier (EDFA) that operates in both C- and L-band wavelength regions is demonstrated. The amplifier employs two pieces of 1.5 m and 9 m-long erbium doped fibers (EDFs) optimized for C-band and L-band operations, respectively, in double-pass parallel configuration to achieve a wideband operation from 1530 to 1605 nm. The chirp fiber Bragg grating is used in both stages to allow a double propagation of signal and thus increases the attainable gain in both C- and L-band regions. At an input signal power of −30 dBm, a measured gain varies from 23 to 36 dB within a wide wavelength region from 1530 to 1605 nm. The corresponding noise figure varies from 5.6 to 8.2 dB within this wavelength region. The gain and noise figure of the proposed parallel configuration is much better when compared to that of a serial amplifier.

Design of broadband erbium-doped fiber amplifier using very high-speed integrated circuit hardware description language for next-generation optical network

We mainly concentrate on the problem of gain broadening and flattening of erbium-doped fiber amplifier (EDFA) using dual forward-pumping configuration in which we use pumping both at 980 and 1480 nm wavelengths. The gain cascading of two EDFAs pumped separately at 980 and 1480 nm combines the advantage of high gain characteristics of 980 nm pumping and broad bandwidth characteristics of 1480 nm pumping. The use of increased number of channels in the present dense wavelength division multiplexing (DWDM) optical network requires a flat gain spectrum across the whole usable bandwidth. The use of very high-speed integrated circuit hardware description language (VHDL-AMS) in lightwave system modeling has been explored. Its application in designing wideband EDFA has not been reported thus far. This work facilitates to design broadband EDFA operating in both the C-band and L-band regions with VHDL-AMS. The amplifier design is made of a dual stage, copumped at 980 and 1480 nm, which delivers an average output power of -16 dBm over the entire 3-dB bandwidth of 80 nm.

Wideband EDFA Based on Erbium Doped Crystalline Zirconia Yttria Alumino Silicate Fiber

A wideband erbium-doped fiber amplifier (EDFA) is demonstrated using an Erbium-doped zirconia fiber as the gain medium. With a combination of both Zr and Al, we could achieve a high erbium doping concentration of 4320 ppm in the glass host without any phase separations of rare-earths. The Erbium doped fiber (EDF) is obtained from a fiber preform, which is fabricated in a ternary glass host, zirconia-yttria-aluminum codoped silica fiber using a MCVD process. Doping of Er2O3 into Zirconia yttria-aluminosilicate based glass is done through solution doping process. The maximum gain of 21.8 dB is obtained at 1560 nm with 2 m long of EDF and co-pumped with 1480 nm laser diode. At high input signal of -4 dBm, a flat-gain at average value of 8.6 dB is obtained with a gain variation of less than 4.4 dB within the wavelength region of 1535-1605 nm and using 3 m of EDF and 100 mW pump power. The corresponding noise figure is maintained below 9.6 dB at this wavelength region.

WAVELENGTH SELECTIVE AUXILIARY C-BAND ASE PUMPING FOR L-BAND EDFA

The variation of Gain and Noise Figure (NF) at 1580 nm with length of Erbium doped fiber (EDF) for two auxiliary pumping schemes employing narrowband Amplified Spontaneous Emission (ASE) and ASE filtered up to a particular wavelength in C-band, by considering a serially cascaded two stage wideband amplifier model are investigated. It is shown that indeed, there exists a wavelength range of ASE for achieving maximum gain. The gain can be increased by 14 dB if wavelength bandwidth of 1480–1554 nm is selected instead of pumping with the broadband ASE (1480–1700 nm). By auxiliary pump using ASE sliced in the 1533 nm window, gain as high as 28 dB and NF as low as 5.5 dB can be achieved for shorter fiber length. To achieve gain of 25–30 dB for the L-band signal only a EDF length of 30 m is required in the case of tuned ASE launching at 1533 nm as compared to 40 m and 65 m by optimized ASE bandwidth and broadband. The values of noise figure do not show significant variation in any of the three configurations. It is apparent that using single wavelength ASE pumping at 1533 nm reduces the fiber length by 10 m (compared to optimized ASE bandwidth pumping) and by 32 m (compared to broadband ASE bandwidth pumping), when L-band EDFA is designed for 25–30 dB signal gain and NF less than 6 dB. These results will be important in designing cascaded wideband EDFA for Optical Fiber Communication (OFC) systems.

Hybrid S- to L-band fiber amplifier module with coupled structure

Erbium-doped fiber amplifiers ~EDFAs! with wide bandwidth are considerably interesting for high-capacity transmission in dense wavelength division multiplexing ~DWDM! systems. However, the transmission capacities in DWDM systems are limited by the gain bandwidth of C-band EDFAs ~1530 to 1560 nm!. Furthermore, L-band ~1560 to 1610 nm! fiber amplifier techniques have been achieved, such as EDFAs using a longer erbium-doped fiber ~EDF! than that of C-band EDFAs, fiber Raman amplifiers, or hybrid amplifiers. In addition, a wide-band EDFA from Cto L-band using a coupled structure has also been studied. In other words, two types of wide-band amplifiers with gain bandwidths of around 100 nm have been reported. The first is a coupled-structure amplifier multiplexing the gain bands, namely, the S-band thulium-doped fluoride fiber amplifier ~TDFA! or fiber Raman amplifier and the C-band and L-band erbium-doped fiber amplifiers. The other is a silica-based fiber Raman amplifier ~S-FRA! featuring a multiwavelength pump technique. Recently, a new S-band ~1450 to 1530 nm! amplification technique, which utilizes erbium-doped silica fiber with a depressed cladding design and a 980-nm pump laser to generate EDF gain extension effects, has been

Hybrid doped fiber amplifier with 100-nm bandwidth for coarse wavelength division multiplexing

A hybrid amplifier spanning from 1468 to 1568nm is constructed by cascading a thulium-doped fiber amplifier pumped at 690 and 1400nm and a Cerium co-doped high concentration wideband erbium-doped fiber amplifier. Results show seamless small signal net gain of 10dB and noise figure maintained below 10dB over the 100-nm gain bandwidth, making the amplifier a promising candidate for coarse wavelength division multiplexing in Metropolitan Area and optical access networks.

Dynamically Gain Control in the Serial Structure>tex<$C+L$>/tex<Wide-Band EDFA

The dynamic gain properties of a serial structure of C+L wide-band EDFA are investigated. It is found out that changing of C band (L band) signal has almost no effect on the gain spectra of L band (C band), so that dynamical gain control can be realized by mature fast linear pump control via monitoring of C band and L band input signal respectively. The method was demonstrated experimentally for the first time.

Advantages of low-cost, miniature, intelligent EDFAs for next-generation dynamic metro/access networks

In this paper, the main characteristics of a low-cost, ultra-compact, and intelligent erbium doped fiber amplifier (EDFA) are introduced and compared with those of the conventional wideband EDFAs. Several reliability concerns that might be raised regarding to the cooler-less compact EDFA are then answered. We also review the major characteristics of erbium doped waveguide amplifiers (EDWAs) and compare the performance and cost-effectiveness with the low-cost, ultra-compact, and intelligent EDFA. Meanwhile comparisons with other sorts of optical amplifiers, such as semiconductor optical amplifier/linear optical amplifier (SOA/LOA), and erbium micro fiber amplifier (EMFA), are also included. Finally we summarize the merits of using narrow band EDFAs against wideband EDFAs in metro/access networks.

Optically gain-clamped wideband erbium-doped fiber amplifier using a common figure-eight feedback-loop lasing light

We propose an optically C plus L-band (1530–1600 nm) silica-based wideband gain-clamped (GC) erbium-doped fiber amplifier (EDFA) using a common figure-eight feedback-loop lasing light at 1568 nm, which is just located within the dead-zone between the C- and L-bands, where no WDM channels can be transmitted. The optical gain and noise figure characteristics of this wideband GC–EDFA in terms of the loop attenuation are examined. This wideband GC–EDFA may find important applications in broadband DWDM networks.

Improvement of4I11/2->4I13/2Transition Rate and Thermal Stabilities in Er3+-Doped TeO2

Spectroscopic and thermal analysis indicates that tellurite glasses doped with B2O3 and GeO2 are promising candidate host materials for wide-band erbium doped fiber amplifier (EDFA) with a high 980 nm pump efficiency. In this study, we measured the thermal stabilities and the emission cross-sections for Er3+: 4I13/2 → 4I15/2 transition in this tellurite glass system. We also determined the Judd-Ofelt parameters and calculated the radiative transition rates and the multiphonon relaxation rates in this glass system. The 15 mol% substitution of B2O3 for TeO2 in the Er3+-doped 75TeO2-20ZnO-5K2O glass raised the multiphonon relaxation rate for 4I11/2 → 4I13/2 transition from 4960 s−1 to 24700 s−1, but shortened the lifetime of the 4I13/2 level by 14 % and reduced the emission cross-section for the 4I13/2 → 4I15/2 transition by 11%. The 15 mol% GeO2 substitution in the same glass system also reduced the emission cross-section but increased the lifetime by 7%. However, the multiphonon relaxation rate for 4I11/2 → 4I13/2 transition was raised merely by 1000 s−1. Therefore, a mixed substitution of B2O3 and GeO2 for TeO2 was concluded to be suitable for the 980 nm pump efficiency and the fluorescence efficiency of 4I13/2 → 4I15/2 transition in Er3+-doped tellurite glasses.

Serial topology of wide-band erbium-doped fiber amplifier for WDM applications

We analyze the recently proposed serial topology of a wide-band erbium-doped fiber amplifier (EDFA) covering both the C- and L-bands and compare it with the parallel configuration of C-band and L-band amplifiers. The analysis is based on an application of a comprehensive large-signal numerical model, which takes into consideration propagation of wavelength-division multiplexing (WDM) signals, bidirectional pump, and both the downstream and upstream ASE power spectral components. We have found that in the multiwavelength regime the new topology can provide output power of 3 dBm/channel for 32 C-band and 40 L-band, 0.8-nm-spaced signals with reasonable pump powers to the first and the second stage. In comparison with the usual parallel configuration of C-band and L-band EDFAs, this topology saves about 20% of overall pump power, 10% of the necessary length of erbium-doped fiber (EDF) and achieves lower noise figure for L-band signals.

Coupled structure for wide-band EDFA with gain and noise figure improvements from C to L-band ASE injection

We propose a novel structure for C plus L-band silica based wide-band erbium-doped fiber amplifiers (W-EDFA's), which use backward amplified spontaneous emission from the C-band EDFA as the pump-mediating injection source for the L-band amplifier unit. Experimental results show gain and noise figure improvements of over 2.6 dB and 0.6 dB, respectively, at -3.5 dBm of L-band input signal power. Spatially resolved numerical analysis confirms the pump-mediating effect of C-band backward ASE in the L-band EDFA for the gain and noise figure improvement, which also provides better understanding on the dynamics of C-band injection seed methods.

Demonstration of 52-nm gain bandwidth over 2400 km (540 dB loss) with gain-equalized low-noise wide-band EDFA's

We successfully demonstrate the compensation of 540-dB transmission loss over 52-nm gain bandwidth by using acoustooptic tunable filters in conjunction with silica-based low-noise wide-band amplifiers. A signal-to-noise rate of over 17 dB (optical) over the whole gain bandwidth has been achieved with very small gain variation (4.3 dB), which corresponds to only 0.8% of the total accumulated gain in the 30 erbium-doped fiber amplifier link.