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Related papers: Modulational instability in $\cal{PT}$-symmetric B…

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We report that conventional saturable periodic structures, in sharp contrast to the conventional systems with different nonlinearities which exhibit the typical S- shaped optical bi- and multi-stable states, reveal some unusual and unique…

Optics · Physics 2024-08-21 S. Vignesh Raja , A. Govindarajan , M. Lakshmanan

To explore resonance phenomena in the nonlinear region, we show by experimental measurements and theoretical analyses that resonance happens in modulation instability (MI) from non-instantaneous nonlinearities in photorefractive crystals.…

Pattern Formation and Solitons · Physics 2018-08-01 Ray-Ching Hong , Chun-Yan Lin , You-Lin Chuang , Chien-Ming Wu , Yonan Su , Jeng Yi Lee , Chien-Chung Jeng , Ming-Feng Shih , Ray-Kuang Lee

This paper presents some numerical simulations of the full one-dimensional Maxwell-Lorentz equations that describe light propagation in fiber Bragg gratings in order to confirm that the standard nonlinear coupled mode equations fail to…

Pattern Formation and Solitons · Physics 2007-05-23 C. Martel , C. M. Casas

The modulational instability of broadband optical pulses in a four-state atomic system is investigated. In particular, starting from a recently derived generalized nonlinear Schr\"odinger equation, a wave-kinetic equation is derived. A…

Pattern Formation and Solitons · Physics 2007-05-23 M. Marklund , P. K. Shukla , R. Bingham , J. T. Mendonca

The interaction between two co-propagating electrostatic wavepackets characterized by arbitrary carrier wavenumber is considered. A one-dimensional (1D) non-magnetized plasma model is adopted, consisting of a cold inertial ion fluid…

Plasma Physics · Physics 2024-03-26 N. Lazarides , Giorgos P. Veldes , Amaria Javed , Ioannis Kourakis

The phenomenon of PT (parity- and time-reversal) symmetry breaking is conventionally associated with a change in the complex mode spectrum of a non-Hermitian system that marks a transition from a purely oscillatory to an exponentially…

The effect of retaining the material dispersion terms in the nonlinear coupled mode equations (NLCME) that describe light propagation in fiber Bragg gratings is analyzed. It is found that dispersion is responsible for new instabilities of…

Pattern Formation and Solitons · Physics 2007-05-23 C. Martel

The nonlinear dynamics of a balanced parity-time symmetric optical microring arrangement are analytically investigated. By considering gain and loss saturation effects, the pertinent conservation laws are explicitly obtained in the Stokes…

The unique spectral behavior exhibited by a class of non-uniform Bragg periodic structures, namely chirped and apodized fiber Bragg gratings (FBGs) influenced by parity and time reversal ($\mathcal{PT}$) symmetry, is presented. The…

Optics · Physics 2020-03-18 S. Vignesh Raja , A. Govindarajan , A. Mahalingam , M. Lakshmanan

We study the modulational instability induced by periodic variations of group-velocity dispersion in the proximity of the zero dispersion point. Multiple instability peaks originating from parametric resonance coexist with the conventional…

Optics · Physics 2023-07-19 Andrea Armaroli , Fabio Biancalana

We analyse the nonlinear dynamics of Fabry-Perot cavities of arbitrary finesse filled by a dispersive Kerr medium, pumped by a continuous wave laser or a synchronous train of flat-top pulses. The combined action of feedback, group velocity…

Solitons are studied in a model of a fiber Bragg grating (BG) whose local reflectivity is subjected to periodic modulation. The superlattice opens an infinite number of new bandgaps in the model's spectrum. Averaging and numerical…

Pattern Formation and Solitons · Physics 2009-11-11 K. Yagasaki , I. M. Merhasin , B. A. Malomed , T. Wagenknecht , A. R. Champneys

We revisit the problem of modulation instability (MI) in optical fibers, including higher-order dispersion terms, self-steepening, and Raman response. We derive expressions for the MI gain and use them to explore the role of self-steepening…

A simple analytical model is developed to analyze and explain the complex dynamics of the multi-peak modulation instability spectrum observed in dispersion oscillating optical fibers [M. Droques et al., 37, 4832-4834 Opt. Lett., (2012)]. We…

Optics · Physics 2015-06-12 M. Droques , A. Kudlinski , G. Bouwmans , G. Martinelli , A. Mussot

In this paper, modulation instability and nonlinear supratransmission are investigated in a one-dimensional chain of atoms using cubic-quartic nonlinearity coefficients. As a result, we establish the discrete nonlinear evolution equation by…

Pattern Formation and Solitons · Physics 2023-08-09 Alphonse Houwe , Souleymanou Abbagari , Lanre Akinyemi , Serge Yamigno Doka , Kofane Timoleon Crepin

We theoretically investigate the phenomenon of modulation instability for systems obeying nonlinear Schr\"odinger equation, which are under the influence of an external homogeneous synthetic magnetic field. For an initial condition, the…

Quantum Gases · Physics 2021-01-13 Karlo Lelas , Ozana Čelan , David Prelogović , Hrvoje Buljan , Dario Jukić

When a monochromatic beam of light propagates through a periodic structure with the incident angle satisfying the Bragg condition, its Fourier spatial spectra oscillates between the resonant modes situated on the edges of the Brillouin…

Optics · Physics 2018-02-09 Paulo A. Brandão , Solange B. Cavalcanti

We study, both theoretically and experimentally, modulational instability in optical fibers that have a longitudinal evolution of their dispersion in the form of a Dirac delta comb. By means of Floquet theory, we obtain an exact expression…

This paper analyses theoretically and numerically the effect of varying grating amplitude on the extremely asymmetrical scattering (EAS) of bulk and guided optical modes in non-uniform strip-like periodic Bragg arrays with stepwise and…

Optics · Physics 2007-05-23 D. K. Gramotnev , T. A. Nieminen

The classical theory of modulation instability (MI) attributed to Bespalov-Talanov in optics and Benjamin-Feir for water waves is just a linear approximation of nonlinear effects and has limitations that have been corrected using the exact…