Zero-dispersion Wavelength Of Optical Fiber Research Articles

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

Dynamics of Raman soliton during supercontinuum generation near the zero-dispersion wavelength of optical fibers

We observe unique dynamics of Raman soliton during supercontinuum process when an input pulse experiences initially normal group-velocity dispersion with a negative dispersion slope. In this situation, the blue components of the spectrum form a Raman soliton that moves faster than the input pulse and eventually decelerates because of Raman-induced frequency downshifting. In the time domain, the soliton trajectory bends and becomes vertical when the Raman shift ceases to occur as the spectrum of Raman soliton approaches the zero dispersion point. Parts of the red components of the pulse spectrum are captured by the Raman soliton through cross-phase modulation and they travel with it. The influence of soliton order, input chirp and dispersion slope on the dynamics of Raman soliton is discussed thoroughly.

Simple Method for Measuring the Zero-Dispersion Wavelength in Optical Fibers

We propose a very simple method for measuring the zero-dispersion wavelength of an optical fiber as well as the ratio between the third- and fourth-order dispersion terms. The method is based on the four-wave mixing process when pumping the fiber in the normal dispersion region, and only requires the measurement of two spectra. We provide an experimental demonstration of the method in a photonic crystal fiber and we show that the measured zero-dispersion wavelength is in good agreement with a low-coherence interferometry measurement.

Zero-dispersion wavelength determination in optical fibers using cross-phase modulation

A simple method for determining the zero-dispersion wavelength in optical fibers is proposed. It is based on cross-phase modulation between a tunable continuous-wave signal and copropagating intense pump pulses in an optical fiber. By positioning the pump wavelength in the normal group-velocity dispersion (GVD) regime, the polarity of the generated pulses at the signal wavelength reverses when the signal wavelength is tuned through the zero-dispersion point from the GVD side. The method was experimentally demonstrated for a /spl sim/1 km dispersion-shifted fiber and a measurement accuracy of /spl sim/0.4 nm was obtained. Simulation results also show good agreement with experimental ones.

High-power femtosecond-pulse reshaping near the zero-dispersion wavelength of an optical fiber

Nonlinear propagation of high-power femtosecond pulses close to the zero-dispersion wavelength of a singlemode optical fiber is studied experimentally and numerically. The roles of four-photon mixing, stimulated Raman scattering, and self-steepening in this process are represented through different extensions of the nonlinear Schrödinger equation.

Stability of bound states near the zero-dispersion wavelength in optical fibers

The propagation of weakly nonlinear pulses near the zero-dispersion wavelength (ZDW) in optical fibers is governed by a modified nonlinear Schr\"odinger (NLS) equation with a third-order-derivative dispersive term. This equation is known to admit steady, multihump bound states that would require less peak power to launch than an ordinary NLS soliton pulse of comparable duration and with carrier wavelength in the anomalous dispersion regime. Here, the stability of the two-hump bound state for which third-order dispersion is most significant is examined. Linear stability analysis indicates the presence of a mild instability with ${O(10}^{\ensuremath{-}2})$ growth rate. Numerical solutions of the modified NLS equation, however, reveal that, under certain conditions, nonlinearity has a stabilizing effect, permitting two-hump pulses to propagate for long distances without collapsing. Depending on the type of perturbation, a perturbed bound state evolves to a neighboring state with carrier frequency shifted either towards or away from the ZDW. The evolution of more general pulse profiles near the ZDW is also considered and the effect of fiber loss is discussed.

Accurate Measurements of the Zero-Dispersion Wavelength in Optical Fibers.

We have developed a frequency-domain phase shift system for measuring the zero-dispersion wavelength and the dispersion slope of single-mode optical fibers. A differential phase shift method and nonlinear four-wave mixing technique were also investigated. The frequency-domain phase shift method is used to produce Standard Reference Materials that have their zero-dispersion wavelengths characterized with an expanded uncertainty (k = 2) of ± 0.060 nm.

On the formation of bound states by interacting nonlocal solitary waves

Steady, multi-hump bound states are constructed asymptotically by matching the oscillatory and exponentially varying tail components of weakly nonlocal solitary waves. The asymptotic procedure is applied to the nonlinear Schrödinger (NLS) equation with a third-order-derivative dispersive term that governs the propagation of pulses near the zero-dispersion wavelength in optical fibers. Families of symmetric, locally confined bound states having two, three and four humps are found analytically for discrete values of the third-order dispersion, consistent with numerical solutions of the perturbed NLS equation. The Korteweg-de Vries equation with a fifth-order-derivative dispersive perturbation — a model equation for gravity-capillary waves on a shallow layer — is also considered, and both symmetric and asymmetric two-hump solution families with oscillatory tails are constructed.