Zero-dispersion Region Research Articles

O-Band $8\times100$ G Data Transmission With 240 GHz Channel Spacing

In this letter, we show an approach to 800G Ethernet based on dense channel allocation in the O-band and successfully demonstrate $8\times 54$ GBaud PAM-4 with narrowest so far 240 GHz channel grid data transmission below HD-FEC over 1 km of standard single mode fiber (SSMF) without any optical amplification, resulting in a total net throughput of 800 Gbit/s. Additionally we study theoretical limits of FWM on 108 Gbit/s channel system in SSMF zero-dispersion region.

Group Delay measurements of ultrabroadband pulses generated in highly nonlinear fibers

Ultra broadband supercontinuum pulses are commonly used as a source of different wavelengths from a wide spectral bandwidth or as a source of very short pulses. However the processes responsible for wide spectral broadening are still under investigation. In this paper we examine the temporal and spectral characteristics of the pulses broadened upon propagation in the highly nonlinear photonics crystal fibers with different dispersion profiles. Generated supercontinuum pulses were experimentally characterized using cross-correlation frequency resolved optical gating technique. Full Text: PDF ReferencesM. Bradler, P. Baum, and E. Riedle, "Femtosecond continuum generation in bulk laser host materials with sub-?J pump pulses", Appl. Phys. B 97, 561 (2009). CrossRef T. M. Kardas, B. Ratajska-Gadomska, W. Gadomski, A. Lapini, and R. Righini, "The role of stimulated Raman scattering in supercontinuum generation in bulk diamond", Opt. Express 21, 24201 (2013). CrossRef A. Brodeur and S. L. Chin, "Band-Gap Dependence of the Ultrafast White-Light Continuum", Phys. Rev. Lett. 80, 4406 (1998). CrossRef R. R. Alfano, ed., The Supercontinuum Laser Source: Fundamentals with Updated References, 2nd ed (Springer, 2006). DirectLink A. L. Gaeta, Phys. "Catastrophic Collapse of Ultrashort Pulses", Rev. Lett. 84, 3582 (2000). CrossRef J. M. Dudley, G. Genty, and S. Coen, "Supercontinuum generation in photonic crystal fiber", Rev. Mod. Phys. 78, 1135 (2006). CrossRef M. Klimczak, B. Siwicki, P. Skibinski, D. Pysz, R. Stepien, A. Heidt, C. Radzewicz, and R. Buczynski, "Coherent supercontinuum generation up to 2.3 ?m in all-solid soft-glass photonic crystal fibers with flat all-normal dispersion", Opt. Express 22, 18824 (2014). CrossRef D. J. Kane and R. Trebino, "Characterization of arbitrary femtosecond pulses using frequency-resolved optical gating", IEEE J. Quantum Electron. 29, 571 (1993). CrossRef J. Dudley, X. Gu, L. Xu, M. Kimmel, E. Zeek, P. O'Shea, R. Trebino, S. Coen, and R. Windeler, "Cross-correlation frequency resolved optical gating analysis of broadband continuum generation in photonic crystal fiber: simulations and experiments", Opt. Express 10, 1215 (2002). CrossRef N. Nishizawa and T. Goto, "Experimental analysis of ultrashort pulse propagation in optical fibers around zero-dispersion region using cross-correlation frequency resolved optical gating", Opt. Express 8, 328 (2001). CrossRef X. Gu, L. Xu, M. Kimmel, E. Zeek, P. O'Shea, A. P. Shreenath, R. Trebino, and R. S. Windeler, "Frequency-resolved optical gating and single-shot spectral measurements reveal fine structure in microstructure-fiber continuum", Opt. Lett. 27, 1174 (2002). CrossRef S. Roy, S. K. Bhadra, and G. P. Agrawal, "Effects of higher-order dispersion on resonant dispersive waves emitted by solitons", Opt. Lett. 34, 2072?2074 (2009). CrossRef S. Bose, S. Roy, R. Chattopadhyay, M. Pal, and S. K. Bhadra, "Experimental and theoretical study of red-shifted solitonic resonant radiation in photonic crystal fibers and generation of radiation seeded Raman soliton", J. Opt. 17, 105506 (2015). CrossRef T. Roger, M. F. Saleh, S. Roy, F. Biancalana, C. Li, and D. Faccio, "High-energy, shock-front-assisted resonant radiation in the normal dispersion regime", Phys. Rev. A 88, (2013). CrossRef G. P. Agrawal, Nonlinear Fiber Optics, Fifth edition (Elsevier/Academic Press, 2013). DirectLink J. Szczepanek, T. Kardas, M. Nejbauer, C. Radzewicz, and Y. Stepanenko, "Simple all-PM-fiber laser system seeded by an all-normal-dispersion oscillator mode-locked with a nonlinear optical loop mirror", Proc. SPIE 9728, 972827 (2016). CrossRef C. Iaconis and I. A. Walmsley, "Self-referencing spectral interferometry for measuring ultrashort optical pulses", IEEE J. Quantum Electron. 35, 501 (1999). CrossRef L. E. Hooper, P. J. Mosley, A. C. Muir, W. J. Wadsworth, and J. C. Knight, "Coherent supercontinuum generation in photonic crystal fiber with all-normal group velocity dispersion", Opt. Express 19, 4902 (2011). CrossRef J. Szczepanek, T. M. Kardas, and Y. Stepanenko, "Sub-160-fs pulses dechriped to its Fourier transform limit generated from the all-normal dispersion fiber oscillator", Optical Society of America Frontiers in Optics conference, FTu3C?2 (2016). CrossRef G. Genty, M. Lehtonen, and H. Ludvigsen, "Effect of cross-phase modulation on supercontinuum generated in microstructured fibers with sub-30 fs pulses", Opt. Express 12, 4614 (2004). CrossRef S. Roy, S. K. Bhadra, K. Saitoh, M. Koshiba, and G. P. Agrawal, "Dynamics of Raman soliton during supercontinuum generation near the zero-dispersion wavelength of optical fibers", Opt. Express 19, 10443 (2011). CrossRef Y. Liu, Y. Zhao, J. Lyngso, S. You, W. L. Wilson, H. Tu, and S. A. Boppart, "Suppressing Short-Term Polarization Noise and Related Spectral Decoherence in All-Normal Dispersion Fiber Supercontinuum Generation", J. Light. Technol. 33, 1814 (2015). CrossRef

超高斯型光脉冲在零色散区传输特性的研究

Based on the non-linear Schrdinger equation which suits the optical soliton propagation,by using the symmetry split-step Fourier transformation,the transmission evolution of super-Gaussin pulse in the zero dispersion region was simulated and the effect of attenuation,high order chromatic dispersion,high order non-linearity and initial chirp on propagation was analyzed.Some conclusions were obtained: attenuation has a great effect on the pulse amplitude but little on the shape of the pulse.The amplitude and pulse width of basic soliton pulse are always at the same standard when the pulse transmitted a certain distance,which is the ideal media for optical communication.As for the high order soliton pulse,it is changing all the time.When all the influence factors come to work together,it has a great effect on the pulse propagation.However,selecting a reasonable combination of these factors,it is possible to get a high order soliton pulse to transmit information.This result has certain amount of valuable reference significance on the study of improving the relay distance between two optical repeaters by strengthening the input power of pulse.

Low Noise C-Band EDFA/DRA Hybrid Amplifier Using the Same Pump Laser

This paper presents the investigation of a hybrid amplifier consisting of Erbium doped fiber amplifiers EDFAs and a distributed Raman amplifier in the C-band. Our simulations take into account all the effects associated with transmitted signals and a pump laser in the optical fiber. The overall noise figure for the proposed hybrid amplifier was less than 10dB, as a limiting case for maximizing the span length and/or minimizing the impairments of fiber nonlinearities. The combination distributed Raman amplifier and EDFAs present better performance than conventional EDFA-only systems. This low noise figure will enable maximum transmission distance. The transmission is discussed of 16 channels spaced 1nm and 1mW of optical power through 100km of fiber. Full Text: PDF References S.K. Kim, S.H. Chang, J.S. Han, M.J. Chu,"Design of hybrid optical amplifiers for high capacity optical transmission", Electron. Telecom. Res. Inst. J. 24, 81 (2002) T.N. Nielson,"Raman Amplifiers in WDM Systems", 12th LEOS Annual Meeting, vol. 2, 471 (1999) T. Suzuki, M. Kakui, M. Hirano, M. Onishi, Y. Nakai, M. Nishimura,"Broadband discrete fiber Raman amplifier with high differential gain operating over 1.65 /spl mu/m-band", Optical Fiber Comm. Conf. MA3 (2001) S. Kawai, H. Masuda, K. Suzuki, K. Aida,"Wide-bandwidth and long-distance WDM transmission using highly gain-flattened hybrid amplifier", IEEE Photon. Technol. Lett. 11, 886 (1999) [CrossRef] W.Y. Oh, S.S. Lee, H. Lee, W. Seo,"16-Channel C-Band Hy-brid Fiber Amplifier Comprising an EDFA and a Single Diode Laser Pumped Dispersion Compensating Raman Amplifier", European Conf. on Comm. 4.4.5, (2000) H. Suzuki, J. Kani, H. Masuda, N. Takachio, K. Iwatsuki, Y. Tada, M. Sumida,"1-Tb/s (100×10 Gb/s) super-dense WDM transmission with 25-GHz channel spacing in the zero-dispersion region employing distributed Raman amplification technology", IEEE Photon. Technol. Lett. 12, 903(2000) [CrossRef] Y. Zhu, W.S. Lee, C. Scahill, C. Fludger, D. Wetly, M. Jones, J. Homan, B. Shaw, A. Hadjifotiou,"1.28 Tbit/s (32×40 Gbit/s) transmission over 1000 km NDSF employing distributed Raman amplification and active gain flattening", Electron. Lett. 33, 43(2001) [CrossRef] B. Zhu, P.B. Hansen, L. Leng, S. Stulz, T.N. Nielsen, C. Doerr, A.J. Stentz, D.S. Vengsarkar, Z.J. Chen, D.W. Peckham, L. Gruner-Nielsen,"800 Gbit/s (80×10.66 Gbit/s) transmission over 3200 km of non-zero dispersion shifted fibre with 100 km amplified spans employing distributed Raman amplification", Electron. Lett. 36, 1860 (2000) [CrossRef] H. Masuda, S. Kawai, K.-I Suzuki,"Optical SNR enhanced amplification in long-distance recirculating-loop WDM transmission experiment using 1580 nm band hybrid amplifier", Electron. Lett. 35, 411 (1999) [CrossRef] D.A. Chestnut, C. J. S. de Matos, J.R. Taylor,"Raman-assisted fiber optical parametric amplifier and wavelength converter in highly nonlinear fiber", J. Opt. Soc. Am. B- 19, 1901 (2002) [CrossRef] A. Carena, V. Curri, P. Poggiolini,"On the optimization of hybrid Raman/erbium-doped fiber amplifiers", IEEE Photon. Technol. Lett. 13, 1170 (2001) [CrossRef] G.E. Tudury, J. Hu, B.S. Marks, A.S. Lenihan, C.R. Menuk, G.M. Carter,"Gain characteristics of a 210 km hybrid Raman/erbium-doped fiber amplified loop", Opt. Comm. 264, 152 (2006) [CrossRef] H. Masuda, Raman Amplifiers for Telecommunications 2, Sub-Systems and Systems (New York, Springer-Verlag 2004) A.W. Naji, B.A. Hamida, X.S. Cheng, M.A. Mahdi, S. Harun, S. Khan, W.F. AL-Khateeb, A.A. Zaidan, B.B. Zaidan, H. Ahmad,"Review of Erbium-doped fiber amplifier", Int. J. Phys.Scien. 6(20), 4674 (2011) A. Sano, T. Kobayashi, E. Yoshida, Y. Miyamoto,"Ultra-high capacity optical transmission technologies for 100 Tbit/s optical transport networks", IEICE Trans. Commun. E94-B (2), 400 (2011)

Stimulated Raman self-scattering of femtosecond pulses. II. The self-compression of Schrödinger solitons in a spectrally inhomogeneous dispersion medium

It is shown that stimulated Raman self-scattering (SRSS) can be efficiently used for the compression of femtosecond optical solitons in optical fibres with the spectrally inhomogeneous frequency dependence of the group-velocity dispersion. The SRS dynamics is studied in detail near the point of the second-order zero dispersion. The saturation of compression of femtosecond solitons in spectrally inhomogeneous fibres in the zero-dispersion region is predicted.

Super-dense WDM transmission technology in the zero-dispersion region employing distributed Raman amplification

This paper describes a practical system design and the transmission performance of high-capacity super-dense-wavelength-division-multiplexing (SD-WDM) transmission in the zero-dispersion region employing distributed Raman amplification (DRA). By combining several semiconductor laser diodes (LDs) of different wavelengths, gain-flattened DRA can be achieved. We quantitatively clarify the relation between the pump power and the maximum input signal power that can be injected into a transmission fiber by taking into account gain saturation due to pump depletion. Based on these analytical results and computer simulations on transmission performance, an SD-WDM transmission experiment is conducted. By employing four-wavelength, backward-pumped DRA and forward-error correction, we successfully demonstrate 1-Tb/s (100 /spl times/ 10 Gb/s) SD-WDM transmission with 25-GHz channel spacing (0.4-b/s/Hz spectral efficiency) in the C-band (zero-dispersion region) over 4 /spl times/ 80 km of dispersion-shifted fiber. These results show that DRA is a powerful technology in realizing high-capacity SD-WDM transmission, particularly in the zero-dispersion region.

Experimental analysis of ultrashort pulse propagation in optical fibers around zero-dispersion region using cross-correlation frequency resolved optical gating

Ultrashort pulse propagation at =1.55 microm in polarization maintaining dispersion shifted fiber is experimentally analyzed using cross-correlated frequency resolved optical gating (X-FROG). The generated soliton pulse is picked out with the spectral filter and is used as the probe pulse. The temporal distributions of the spectral components in the generated pulses are observed. The initial process of the pulse breakup is directly observed for the first time. The results of X-FROG traces are in agreement with the measured cross-correlation traces and the optical spectra. It is shown that the generated soliton pulse and the anti-stokes pulse are partially overlapped and almost copropagate along the fiber.

1-Tb/s (100 x 10 Gb/s) super-dense WDM transmission with 25-GHz channel spacing in the zero-dispersion region employing distributed Raman amplification technology

We achieve 1 Tb/s (100/spl times/10 Gb/s) super-dense WDM (super DWDM) transmission with 25-GHz channel spacing (0.4 bit/s/Hz spectral efficiency) in the zero-dispersion region over a 4/spl times/80 km dispersion-shifted fiber by employing backward pumped distributed Raman amplification and forward error correction. By adopting bi-directional pumping, we present experimental results showing that the transmission distance is extended approximately threefold to 1040 km.

50 GHz spaced, 32 × 10 Gbit/s dense WDM transmissionin zero-dispersion region over 640 km of dispersion-shifted fibre with multiwavelength distributed Raman amplification

The authors present, for the first time, 32/spl times/10 Gbit/s transmission (50 GHz channel spacing) in the zero-dispersion region of dispersion-shifted fibre (DSF) by employing multiwavelength distributed Raman amplification. Each transmission span is bi-directionally pumped at two wavelengths, 1450 and 1465 nm, to construct a wideband distributed Raman amplifier. A hybrid amplifier formed by a gain-flattened erbium-doped fibre amplifier and a gain-flattened distributed Raman amplifier is used to successfully realise dense WDM transmission in the zero-dispersion region over 8/spl times/80 km of DSF.

Erratum: ?Succession of one-soliton pulses in the zero-dispersion region of silica optical fibres: the role of the phase difference between adjacent pulses?

Erratum: ?Succession of one-soliton pulses in the zero-dispersion region of silica optical fibres: the role of the phase difference between adjacent pulses?

Influence of the initial phase difference between pulses on the N-soliton interaction in trains of unequal solitons in optical fibers

A numerical investigation of the influence of the initial phase difference π between the pulses of the N-soliton interaction in trains of unequal solitons in optical fibers is performed. Carrier frequencies in and far away from the zero-dispersion region are considered. It has been shown that the introduction of the initial phase difference π between adjacent pulses in trains of unequal solitons could not be considered as a method for reducing the N-soliton interaction.

Succession of one-soliton pulses in the zero-dispersion region of silica optical fibres: The role of the phase difference between the adjacent pulses

Some features of the propagation of one-soliton successions in the third order dispersion region are presented for the case where the phase difference between adjacent pulses is π rads. We show that this considerably improves the stability of the pulses in the zero-dispersion region. Walk-off can be diminished by increasing the number of pulses in the succession. These features may help optimize the bandwidth of non-linear fibre communication links.

Propagation of one-soliton pulses succession in monomode optical fibers

The stability of one-soliton equidistant pulses succession has been investigated for the number of pulses in the succession varying from 2 to 6. Two cases for the carrier wavelength are presented: far from the zero-dispersion region, and in it. In the first case it is shown that if the phase difference between every two adjacent pulses is equal to π the influence of the interaction forces on the stability of the pulse succession propagation progressively decreases with the increase of the number of the pulses. In the second case it is shown that for small initial distances between the pulses the third-order dispersion can both reduce and amplify the interaction between the solitons, depending on the number of the solitons in the succession.

Single-mode fiber dispersion measurements using optical sampling with a mode-locked laser diode

Pulses from a wavelength-tunable, mode-locked laser diode were measured after 21 km of single-mode fiber propagation by optical sampling with another mode-locked laser diode; a resolution of 0.1 psec/(nm km) is achieved in this chromatic dispersion measurement. In another related experiment, 78-psec-duration pulses from an ordinary, multilongitudinal-mode laser diode are clearly displayed by optical sampling after 36 km of fiber propagation. System bandwidth increases to approximately 500 GHz km as the laser-diode wavelength is temperature tuned through the zero-dispersion region.

Optical transmission in dispersion-shifted single mode spliced fibers and cables

Dispersion-shifted single mode fibers have been fabricated with losses as low as 0.21 dB/km in the zero-dispersion region ( \lambda_{0} \approx 1.5-1.6 \mu m). Low-loss (average = 0.06-dB) fusion splices have been made with the chlorine-hydrogen flame fusion technique. The recoated splices show strengths in excess of 300 kpsi. The fibers have been incorporated into a cable structure with negligible change in loss.