Generation of Self-Similar Parabolic Pulses by Designing Normal Dispersion Decreasing Fiber Amplifier as Well as Its Staircase Substitutes
TL;DR: In this article, the virtual gain arising from the unavoidable spatial nonlinear variation was introduced to obtain the self-similar parabolic pulses at smaller optimum length in comparison to NDDF with constant nonlinearity.
Abstract: Generation of self-similar parabolic pulse is analytically and numerically demonstrated by designing parabolic index normal dispersion decreasing fiber (NDDF) amplifiers. The pulse transmission is extensively studied for NDDFs in presence of physical gain as well as virtual gain induced by two different dispersion profiles corresponding to two different physical gain coefficients. Here, we introduce the virtual gain arising from the unavoidable spatial nonlinear variation, which helps to obtain the self-similar parabolic pulses at smaller optimum length in comparison to NDDF with constant nonlinearity. The output power profiles resemble with a perfect parabolic shape giving rise to self-similar pulses with very small misfit parameters. Pulse propagation in presence of spatial gain variation is also studied. To avoid fabrication difficulties, we propose equivalent staircase dispersion profiles consisting of a number of constant dispersion fibers (CDFs), which are simple to manufacture and show performances excellently close to that of the proposed NDDF.
Citations
More filters
01 Jan 2001
TL;DR: The development of new highly nonlinear fibers, referred to as microstructured fibers, holey fibers and photonic crystal fibers, is the next generation technology for all-optical signal processing and biomedical applications as mentioned in this paper.
Abstract: * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The book presents sound coverage of the fundamentals of lightwave technology, along with material on pulse compression techniques and rare-earth-doped fiber amplifiers and lasers. The extensively revised chapters include information on fiber-optic communication systems and the ultrafast signal processing techniques that make use of nonlinear phenomena in optical fibers.New material focuses on the applications of highly nonlinear fibers in areas ranging from wavelength laser tuning and nonlinear spectroscopy to biomedical imaging and frequency metrology. Technologies such as quantum cryptography, quantum computing, and quantum communications are also covered in a new chapter.This book will be an ideal reference for: RD scientists involved with research on fiber amplifiers and lasers; graduate students and researchers working in the fields of optical communications and quantum information. * The only book on how to develop nonlinear fiber optic applications* Two new chapters on the latest developments; Highly Nonlinear Fibers and Quantum Applications* Coverage of biomedical applications
595 citations
TL;DR: In this paper, the relationship between the self-similar propagation region for single pulse and oscillation region for a pair of selfsimilar pulses is investigated. And the results are beneficial in Dense Wavelength Division Multiplexing transmission system which is in heavy demands of light source in wide-range wavelength.
Abstract: The relationship between the self-similar propagation region for single pulse and oscillation region for a pair of self-similar pulses are first investigated in our paper. By introducing self-similar coefficient F and RMS width ratio K, we find that self-similar propagation region starts from z = 1.8LD to z = 18LD while F ≤ 10%. The optimum output of self-similar pulse is also achieved when F and K reach a minimum value simultaneously at z = 3.5LD. The sinusoidal fit oscillation region of self-similar pulse pair ranges from 5/8LD to 2LD while F varies from 40.27 to 7.99%, and the dark soliton fit oscillation region ranges from 2LD to 6LD while F varies from 7.99 to 5.32%, indicating that the sinusoidal fit oscillation region almost occurs before the pulses enter the self-similar propagation region and the dark soliton fit oscillation region occurs within the self-similar pulse propagation region. Furthermore, the oscillation characteristics of interacting pulses are also studied numerically by using split-step Fourier method. The results are beneficial in Dense Wavelength Division Multiplexing transmission system which is in heavy demands of light source in wide-range wavelength.
8 citations
TL;DR: In this article, three different silica-based normal dispersion fibers are designed to identify the best possible one for efficient parabolic pulse generation, which is the best choice for fiber optic manufacturers for parabolic similariton formation due to its smaller optimum length, no effect of higher order dispersion, high nonlinearity and less input power requirement.
Abstract: Three different silica based normal dispersion fibers are designed to identify the best possible one for efficient parabolic pulse generation. Two of them resemble commonly used single core fibers and optimized in such a way that one has lower dispersion and nonlinear coefficient whereas the other possesses higher dispersion and lower nonlinearity. A silica based multi-cladded highly nonlinear fiber (ND-HNLF) is designed as well by successfully restricting its effective area to a very lower value. The comparative analysis among the three fibers suggests that the ND-HNLF would be the best choice for fiber optic manufacturers for parabolic similariton formation due to its smaller optimum length, no effect of higher order dispersion, high nonlinearity and less input power requirement. From our proposed ND-HNLF, a highly nonlinear dispersion decreasing fiber (HN-NDDF) is also designed and optimized by properly varying different fiber parameters as a function of fiber length. Our study also reveals that the HN-NDDF with a typical property of virtual gain would be beneficial for producing parabolic self-similar pulses at smaller optimum lengths with adequate spectral broadening in comparison to that of ND-HNLF.
7 citations
Cites background or methods from "Generation of Self-Similar Paraboli..."
...5 (Ghosh et al. 2009)....
[...]
...where D(z), T(z) and C(z) represent the normalized variation of GVD, TOD and nonlinear coefficient along the length of the fiber (Ghosh et al. 2009)....
[...]
...At the same time, we consider a normal dispersion decreasing fiber amplifier with a typical dispersion profile as given by (Ghosh et al. 2009; Wabnitz and Finot 2008)...
[...]
...It is already known that the effective gain coefficient d (Ghosh et al. 2009) of the NDDF depends on the variation of dispersion and nonlinearity in addition to the physical gain coefficient d0 (Ghosh et al....
[...]
...2009; Wabnitz and Finot 2008), d is the effective gain coefficient (Ghosh et al. 2009; Wabnitz and Finot 2008) and...
[...]
TL;DR: Based on the nonlinear Schrodinger equation and the linearly chirped parabolic pulse generation in the dispersion decreasing fiber with normal dispersion, a novel scheme for the generation of the self-similar parabolic pulses via a comb-like profiled dispersion fiber, with normal group-velocity dispersion has been proposed and the corresponding model is established as discussed by the authors.
7 citations
TL;DR: A multicladded normally dispersive erbium-doped fiber amplifier (ND-EDFA) is designed for a short length to operate at the wavelength of 1550 nm with a dispersion of −6.5 ps∕kmnm and parabolic pulse gener- ation through the proposed fiber is studied in this paper.
Abstract: A multicladded normally dispersive erbium-doped fiber amplifier (ND-EDFA) is designed for a short length to operate at the wavelength of 1550 nm with a dispersion of −6.5 ps∕kmnm and parabolic pulse gener- ation through the proposed fiber is studied. The proposed ND-EDFA shows a flattened gain spectrum in C-band. The nonlinear Schrodinger equation is solved numerically in presence of fiber gain, nonlinearity, and dispersion to investigate the pulse propagation through the proposed fiber. While continuous wave (CW) sources are considered, parabolic self- similar pulses with structure factor of 0.072 are created at suitable values of optimum fiber length when input pulse properties and fiber parameters are optimized accordingly. Side by side with a low repetition rate laser source, the pulse propagation equation is controlled by the gain dispersion term and dipole relaxation time, such that the evolution of Gaussian pulses may lead to nonparabolic regime. The effects of pulse parameters like power level, pulse width, and dipole relaxation time on the propagation of input Gaussian pulses through the so-designed ND-EDFA are investi- gated. Our results depict that the pulses with same input energy reshape into exactly parabolic shape for CW laser source or nonparabolic profile for
6 citations
References
More filters
Book•
01 Jan 1989TL;DR: The field of nonlinear fiber optics has advanced enough that a whole book was devoted to it as discussed by the authors, which has been translated into Chinese, Japanese, and Russian languages, attesting to the worldwide activity in the field.
Abstract: Nonlinear fiber optics concerns with the nonlinear optical phenomena occurring inside optical fibers. Although the field ofnonlinear optics traces its beginning to 1961, when a ruby laser was first used to generate the second-harmonic radiation inside a crystal [1], the use ofoptical fibers as a nonlinear medium became feasible only after 1970 when fiber losses were reduced to below 20 dB/km [2]. Stimulated Raman and Brillouin scatterings in single-mode fibers were studied as early as 1972 [3] and were soon followed by the study of other nonlinear effects such as self- and crossphase modulation and four-wave mixing [4]. By 1989, the field ofnonlinear fiber optics has advanced enough that a whole book was devoted to it [5]. This book or its second edition has been translated into Chinese, Japanese, and Russian languages, attesting to the worldwide activity in the field of nonlinear fiber optics.
15,770 citations
TL;DR: Self-similarity analysis of the nonlinear Schrödinger equation with gain results in an exact asymptotic solution corresponding to a linearly chirped parabolic pulse which propagates self-similarly subject to simple scaling rules.
Abstract: Ultrashort pulse propagation in high gain optical fiber amplifiers with normal dispersion is studied by self-similarity analysis of the nonlinear Schrodinger equation with gain. An exact asymptotic solution is found, corresponding to a linearly chirped parabolic pulse which propagates self-similarly subject to simple scaling rules. The solution has been confirmed by numerical simulations and experiments studying propagation in a Yb-doped fiber amplifier. Additional experiments show that the pulses remain parabolic after propagation through standard single mode fiber with normal dispersion.
742 citations
"Generation of Self-Similar Paraboli..." refers background in this paper
...In this approach, the reshaping of pulses in parabolic form leads to acquire the properties of optical similariton [1], through certain conserving relations between energy, pulse width, and frequency chirp due to phase modulation....
[...]
...I N recent years, linearly chirped parabolic pulses in normal dispersion optical fibers have drawn considerable research interests [1]–[13]....
[...]
Book•
30 Jan 2001TL;DR: The development of new highly nonlinear fibers, referred to as microstructured fibers, holey fibers and photonic crystal fibers, is the next generation technology for all-optical signal processing and biomedical applications as discussed by the authors.
Abstract: * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The book presents sound coverage of the fundamentals of lightwave technology, along with material on pulse compression techniques and rare-earth-doped fiber amplifiers and lasers. The extensively revised chapters include information on fiber-optic communication systems and the ultrafast signal processing techniques that make use of nonlinear phenomena in optical fibers.New material focuses on the applications of highly nonlinear fibers in areas ranging from wavelength laser tuning and nonlinear spectroscopy to biomedical imaging and frequency metrology. Technologies such as quantum cryptography, quantum computing, and quantum communications are also covered in a new chapter.This book will be an ideal reference for: RD scientists involved with research on fiber amplifiers and lasers; graduate students and researchers working in the fields of optical communications and quantum information. * The only book on how to develop nonlinear fiber optic applications* Two new chapters on the latest developments; Highly Nonlinear Fibers and Quantum Applications* Coverage of biomedical applications
702 citations
01 Jan 2001
TL;DR: The development of new highly nonlinear fibers, referred to as microstructured fibers, holey fibers and photonic crystal fibers, is the next generation technology for all-optical signal processing and biomedical applications as mentioned in this paper.
Abstract: * The only book describing applications of nonlinear fiber optics * Two new chapters on the latest developments: highly nonlinear fibers and quantum applications* Coverage of biomedical applications* Problems provided at the end of each chapterThe development of new highly nonlinear fibers - referred to as microstructured fibers, holey fibers and photonic crystal fibers - is the next generation technology for all-optical signal processing and biomedical applications. This new edition has been thoroughly updated to incorporate these key technology developments.The book presents sound coverage of the fundamentals of lightwave technology, along with material on pulse compression techniques and rare-earth-doped fiber amplifiers and lasers. The extensively revised chapters include information on fiber-optic communication systems and the ultrafast signal processing techniques that make use of nonlinear phenomena in optical fibers.New material focuses on the applications of highly nonlinear fibers in areas ranging from wavelength laser tuning and nonlinear spectroscopy to biomedical imaging and frequency metrology. Technologies such as quantum cryptography, quantum computing, and quantum communications are also covered in a new chapter.This book will be an ideal reference for: RD scientists involved with research on fiber amplifiers and lasers; graduate students and researchers working in the fields of optical communications and quantum information. * The only book on how to develop nonlinear fiber optic applications* Two new chapters on the latest developments; Highly Nonlinear Fibers and Quantum Applications* Coverage of biomedical applications
595 citations
"Generation of Self-Similar Paraboli..." refers background or methods in this paper
...Considering a bidirectionally pumped distributed amplifier the gain variation is given by [17]...
[...]
...The output rms pulse widths [16], [17] and spectral widths [16], [17] of the linearly chirped parabolic pulses are estimated and are plotted as a function of propagating distance in km in Fig....
[...]
...The propagation of pulses in optical fibers with varying dispersion is well described by NLSE with gain [15]–[17]...
[...]
TL;DR: In this article, a direct numerical integration of the wave equation is used to establish the validity of approximating the fundamental mode of graded-index fibers by a Gaussian function, and the fundamental modes of fibers, whose index profile can be expressed as a power law, are indeed very nearly Gaussian in shape.
Abstract: Direct numerical integration of the wave equation is used to establish the validity of approximating the fundamental mode of graded-index fibers by a Gaussian function. We show that the fundamental modes of fibers, whose index profile can be expressed as a power law, are indeed very nearly Gaussian in shape (that is probably also true for graded-index fibers with convex profiles other than a power law). Graphs and empirical analytical expressions are presented for the optimum Gaussian beam width parameter and for the propagation constant of the fundamental mode.
445 citations