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Goëry Genty - One of the best experts on this subject based on the ideXlab platform.
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extreme events prediction in optical fibre Modulation Instability using machine learning
European Quantum Electronics Conference, 2019Co-Authors: L. Salmela, Mikko Narhi, Cyril Billet, Juha Toivonen, J M Dudley, Coraline Lapre, Goëry GentyAbstract:The study of instabilities that drive extreme events is central to nonlinear science. One of the most celebrated example of nonlinear Instability is Modulation Instability (MI) which describes the exponential amplification of noise on top of an input signal. When seeded by noise, MI has been shown to be associated with the emergence of high intensity localized temporal breathers with random statistics and it has also been suggested that MI may be linked to the formation of extreme events or rogue waves [1], Real-time techniques such as the dispersive Fourier transform (DFT) are commonly used to measure ultrafast instabilities [2], Although conceptually simple and easy to implement, the DFT only provides spectral information, limiting the knowledge of associated temporal properties. Here, we show how machine learning can overcome this restriction to study time-domain properties of optical fibre Modulation Instability based only on spectral intensity measurements. Specifically, we train a supervised neural network (NN) to correlate the spectral and temporal properties of Modulation Instability using numerical simulations, and then we apply the neural network model to analyse high dynamic range experimental MI spectra to yield the probability distribution for the highest temporal peaks in the Instability field [3].
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Machine learning analysis of extreme events in optical fibre Modulation Instability
Nature Communications, 2018Co-Authors: M. Närhi, John Michaël Dudley, Cyril Billet, L. Salmela, Juha Toivonen, Goëry GentyAbstract:A central research area in nonlinear science is the study of instabilities that drive extreme events. Unfortunately, techniques for measuring such phenomena often provide only partial characterisation. For example, real-time studies of instabilities in nonlinear optics frequently use only spectral data, limiting knowledge of associated temporal properties. Here, we show how machine learning can overcome this restriction to study time-domain properties of optical fibre Modulation Instability based only on spectral intensity measurements. Specifically, a supervised neural network is trained to correlate the spectral and temporal properties of Modulation Instability using simulations, and then applied to analyse high dynamic range experimental spectra to yield the probability distribution for the highest temporal peaks in the Instability field. We also use unsupervised learning to classify noisy Modulation Instability spectra into subsets associated with distinct temporal dynamic structures. These results open novel perspectives in all systems exhibiting Instability where direct time-domain observations are difficult.
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Real time measurements of spontaneous breathers generated by Modulation Instability in optical fibre
2017Co-Authors: John Michaël Dudley, Goëry Genty, Mikko Narhi, Benjamin Wetzel, Cyril Billet, Jean Merolla, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R MorandottiAbstract:Modulation Instability is a fundamental process of nonlinear physics, leading to the unstable breakup of a constant amplitude solution of a particular physical system. There has been particular interest in studying Modulation Instability in the cubic nonlinear Schrödinger equation (NLSE) which models a wide range of nonlinear systems including superfluids, fiber optics, plasmas and Bose-Einstein condensates. Modulation Instability in the NLSE is also a significant current area of study in the context of understanding the emergence of high amplitude or high intensity events that satisfy "rogue wave" statistical criteria. Here, exploiting recent advances in real time ultrafast optical metrology via an optical time lens system, we perform real-time measurements in an NLSE optical fibre system of the unstable breakup of a continuous wave field, simultaneously characterising emergent Modulation Instability breathers, and their associated statistics. Our results allow quantitative comparison between experiment, modelling, and theory, and we show very good agreement in both extracted intensity profiles and associated statistics.
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Direct Measurement of Temporal Rogue Waves Generated by Spontaneous Modulation Instability
2016Co-Authors: Mikko Narhi, Goëry Genty, Benjamin Wetzel, Cyril Billet, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R Morandotti, Jean-marc Merolla, John Michaël DudleyAbstract:We measure the real time intensity profiles of localized structures emerging from spontaneous Modulation Instability. We show that the results can be interpreted in terms of analytical solutions of the nonlinear Schrödinger equation.
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Real-time measurements of spontaneous breathers and rogue wave events in optical fibre Modulation Instability
Nature Communications, 2016Co-Authors: Mikko Narhi, Goëry Genty, Benjamin Wetzel, Cyril Billet, Jean Merolla, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R Morandotti, John Michaël DudleyAbstract:Modulation Instability is a fundamental process of nonlinear science, leading to the unstable breakup of a constant amplitude solution of a physical system. There has been particular interest in studying Modulation Instability in the cubic nonlinear Schrödinger equation, a generic model for a host of nonlinear systems including superfluids, fibre optics, plasmas and Bose–Einstein condensates. Modulation Instability is also a significant area of study in the context of understanding the emergence of high amplitude events that satisfy rogue wave statistical criteria. Here, exploiting advances in ultrafast optical metrology, we perform real-time measurements in an optical fibre system of the unstable breakup of a continuous wave field, simultaneously characterizing emergent Modulation Instability breather pulses and their associated statistics. Our results allow quantitative comparison between experiment, modelling and theory, and are expected to open new perspectives on studies of Instability dynamics in physics.
John Michaël Dudley - One of the best experts on this subject based on the ideXlab platform.
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Machine learning analysis of extreme events in optical fibre Modulation Instability
Nature Communications, 2018Co-Authors: M. Närhi, John Michaël Dudley, Cyril Billet, L. Salmela, Juha Toivonen, Goëry GentyAbstract:A central research area in nonlinear science is the study of instabilities that drive extreme events. Unfortunately, techniques for measuring such phenomena often provide only partial characterisation. For example, real-time studies of instabilities in nonlinear optics frequently use only spectral data, limiting knowledge of associated temporal properties. Here, we show how machine learning can overcome this restriction to study time-domain properties of optical fibre Modulation Instability based only on spectral intensity measurements. Specifically, a supervised neural network is trained to correlate the spectral and temporal properties of Modulation Instability using simulations, and then applied to analyse high dynamic range experimental spectra to yield the probability distribution for the highest temporal peaks in the Instability field. We also use unsupervised learning to classify noisy Modulation Instability spectra into subsets associated with distinct temporal dynamic structures. These results open novel perspectives in all systems exhibiting Instability where direct time-domain observations are difficult.
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Real time measurements of spontaneous breathers generated by Modulation Instability in optical fibre
2017Co-Authors: John Michaël Dudley, Goëry Genty, Mikko Narhi, Benjamin Wetzel, Cyril Billet, Jean Merolla, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R MorandottiAbstract:Modulation Instability is a fundamental process of nonlinear physics, leading to the unstable breakup of a constant amplitude solution of a particular physical system. There has been particular interest in studying Modulation Instability in the cubic nonlinear Schrödinger equation (NLSE) which models a wide range of nonlinear systems including superfluids, fiber optics, plasmas and Bose-Einstein condensates. Modulation Instability in the NLSE is also a significant current area of study in the context of understanding the emergence of high amplitude or high intensity events that satisfy "rogue wave" statistical criteria. Here, exploiting recent advances in real time ultrafast optical metrology via an optical time lens system, we perform real-time measurements in an NLSE optical fibre system of the unstable breakup of a continuous wave field, simultaneously characterising emergent Modulation Instability breathers, and their associated statistics. Our results allow quantitative comparison between experiment, modelling, and theory, and we show very good agreement in both extracted intensity profiles and associated statistics.
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Direct Measurement of Temporal Rogue Waves Generated by Spontaneous Modulation Instability
2016Co-Authors: Mikko Narhi, Goëry Genty, Benjamin Wetzel, Cyril Billet, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R Morandotti, Jean-marc Merolla, John Michaël DudleyAbstract:We measure the real time intensity profiles of localized structures emerging from spontaneous Modulation Instability. We show that the results can be interpreted in terms of analytical solutions of the nonlinear Schrödinger equation.
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Real-time measurements of spontaneous breathers and rogue wave events in optical fibre Modulation Instability
Nature Communications, 2016Co-Authors: Mikko Narhi, Goëry Genty, Benjamin Wetzel, Cyril Billet, Jean Merolla, Shanti Toenger, Thibaut Sylvestre, Frédéric Dias, R Morandotti, John Michaël DudleyAbstract:Modulation Instability is a fundamental process of nonlinear science, leading to the unstable breakup of a constant amplitude solution of a physical system. There has been particular interest in studying Modulation Instability in the cubic nonlinear Schrödinger equation, a generic model for a host of nonlinear systems including superfluids, fibre optics, plasmas and Bose–Einstein condensates. Modulation Instability is also a significant area of study in the context of understanding the emergence of high amplitude events that satisfy rogue wave statistical criteria. Here, exploiting advances in ultrafast optical metrology, we perform real-time measurements in an optical fibre system of the unstable breakup of a continuous wave field, simultaneously characterizing emergent Modulation Instability breather pulses and their associated statistics. Our results allow quantitative comparison between experiment, modelling and theory, and are expected to open new perspectives on studies of Instability dynamics in physics.
L O Silva - One of the best experts on this subject based on the ideXlab platform.
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self Modulation Instability of ultra relativistic particle bunches with finite rise times
arXiv: Plasma Physics, 2014Co-Authors: J Vieira, L D Amorim, Y Fang, W B Mori, P Muggli, L O SilvaAbstract:We study the evolution of the self-Modulation Instability using bunches with finite rise times. Using particle-in-cell simulations we show that unlike long bunches with sharp rise times, there are large variations of the wake amplitudes and wake phase velocity when bunches with finite rise times are used. These results show that use of bunches with sharp rise times is important to seed the self-Modulation Instability and to ensure stable acceleration regimes.
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self Modulation Instability of ultra relativistic particle bunches with finite rise times
Plasma Physics and Controlled Fusion, 2014Co-Authors: J Vieira, L D Amorim, Y Fang, W B Mori, P Muggli, L O SilvaAbstract:We study the evolution of the self-Modulation Instability for bunches with finite rise times. Using particle-in-cell simulations we show that, unlike with long bunches with sharp rise times, there are large variations of the wake amplitude and phase velocity with finite rise time bunches. These results show that bunches with sharp rise times are important to seed the self-Modulation Instability and to ensure stable acceleration.
Demetrios N. Christodoulides - One of the best experts on this subject based on the ideXlab platform.
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(1+1)-Dimensional Modulation Instability of spatially incoherent light
Journal of The Optical Society of America B-optical Physics, 2002Co-Authors: Marin Soljacic, Mordechai Segev, Suzanne Sears, Demetrios N. ChristodoulidesAbstract:We present a comprehensive study of the one-dimensional Modulation Instability of partially spatially incoherent light in noninstantaneous self-focusing media. For this Instability to occur, the nonlinearity has to exceed a specific threshold that depends on the coherence properties of the beam. Above this threshold a uniform-intensity partially spatially coherent wave front becomes unstable and breaks up into periodic trains of one-dimensional stripes.
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Modulation Instability and pattern formation in spatially incoherent light beams
Science, 2000Co-Authors: Detlef Kip, Marin Soljacic, Mordechai Segev, Eugenia D Eugenieva, Demetrios N. ChristodoulidesAbstract:We report on the experimental observation of Modulation Instability of partially spatially incoherent light beams in noninstantaneous nonlinear media and show that in such systems patterns can form spontaneously from noise. Incoherent Modulation Instability occurs above a specific threshold that depends on the coherence properties (correlation distance) of the wave packet and leads to a periodic train of one-dimensional filaments. At a higher value of nonlinearity, the incoherent one-dimensional filaments display a two-dimensional Instability and break up into self-ordered arrays of light spots. This discovery of incoherent pattern formation reflects on many other nonlinear systems beyond optics. It implies that patterns can form spontaneously (from noise) in diverse nonlinear many-body systems involving weakly correlated particles, such as atomic gases at (or near) Bose-Einstein condensation temperatures and electrons in semiconductors at the vicinity of the quantum Hall regime.
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Modulation Instability of incoherent beams in noninstantaneous nonlinear media
Physical review letters, 2000Co-Authors: Marin Soljacic, Mordechai Segev, Tamer H. Coskun, Demetrios N. Christodoulides, Ashvin VishwanathAbstract:We show that Modulation Instability can exist with partially spatially incoherent light beams in a noninstantaneous nonlinear environment. For such incoherent Modulation Instability to occur, the value of the nonlinearity has to exceed a threshold imposed by the degree of spatial coherence.
Stuart G. Murdoch - One of the best experts on this subject based on the ideXlab platform.
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characterization of chromatic dispersion in photonic crystal fibers using scalar Modulation Instability
Optics Express, 2005Co-Authors: G K L Wong, Stuart G. Murdoch, A Y H Chen, R J Kruhlak, R Leonhardt, J D Harvey, N Y JolyAbstract:A simple and accurate method is proposed for characterizing the chromatic dispersion of high air-filling fraction photonic crystal fibers. The method is based upon scalar Modulation Instability generated by a strong pump wave propagating near the zero-dispersion wavelength. Measuring the Modulation Instability sideband frequency shifts as a function of wavelength gives a direct measurement of the fiber’s chromatic dispersion over a wide wavelength range. To simplify the dispersion calculation we introduce a simple analytical model of the fiber’s dispersion, and verify its accuracy via a full numerical simulation. Measurements of the chromatic dispersion of two different types of high air-filling fraction photonic crystal fibers are presented.
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Nonlinear dynamics of polarization Modulation Instability in optical fiber
Journal of The Optical Society of America B-optical Physics, 1997Co-Authors: Stuart G. Murdoch, Rainer Leonhardt, John HarveyAbstract:The nonlinear dynamics of polarization Modulation Instability in the strong conversion regime is investigated both theoretically and experimentally. We observe oscillations in the polarization Modulation Instability sidebands’ power as a function of input-pump power. These oscillations correspond to the changing direction of the flow of energy between the sidebands and the pump. With the inclusion of Raman gain between the three waves, good agreement is found between theory and experiment.
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Polarization Modulation Instability in weakly birefringent fibers
Optics letters, 1995Co-Authors: Stuart G. Murdoch, Rainer Leonhardt, John D. HarveyAbstract:Modulation Instability generated by the coherent interaction of two polarization modes in a weakly birefringent optical fiber has been observed in the normal dispersion regime. In contrast to previous observations of cross-phase-Modulation Instability in the visible, the two generated sidebands have the same polarization, which is orthogonal to that of the pump, and their frequency shift is readily controlled by variation of the birefringence of the fiber. The frequency of the Modulation and its qualitative features agree with those theoretically predicted.
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The effect of resonant dispersion and gain on Modulation Instability
Optics Communications, 1995Co-Authors: Stuart G. Murdoch, John D. Harvey, Nelson ChristensenAbstract:The effect of resonant dispersion on the development of both scalar and polarisation Modulation Instability in a doped amplifying fiber is considered. Polarisation Modulation Instability can occur in a gain fiber even when scalar Modulation Instability is suppressed. Resonant dispersion is shown to have an important influence on the Modulation Instability spectrum.