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We study the traversal times of electromagnetic pulses across dispersive media with negative dielectric permittivity ($\varepsilon$) and magnetic permeability ($\mu$) parameters. First we investigate the transport of optical pulses through…

Materials Science · Physics 2008-12-08 Lipsa Nanda , S. Anantha Ramakrishna

Gonz\'alez et al. (2003) have reported the discovery of an anomalous radiation component from ~ 1 -- 200 MeV in GRB 941017. This component varies independently of and contains >~ 3 times the energy found in the prompt ~ 50 keV -- 1 MeV…

Astrophysics · Physics 2009-11-10 C. D. Dermer , A. Atoyan

Anomalous diffusion is the fundamental ansatz of phenomenological theories of passive scalar turbulence, and has been confirmed numerically and experimentally to an extraordinary extent. The purpose of this survey is to discuss our recent…

Analysis of PDEs · Mathematics 2025-09-05 Scott Armstrong , Vlad Vicol

A strong light pulse propagating in a nonlinear medium causes an effective change in the local refractive index. With a suitable tuning of the pulse velocity, the leading and trailing edge of the pulse were predicted to behave as analogue…

Optics · Physics 2012-08-07 Stefano Finazzi , Iacopo Carusotto

In conventional plasmonic media and plasmonic metamaterials, such as metallic wire mesh, longitudinal mode of electromagnetic wave manifests itself in frequency overlapping transverse modes, which impedes clear observation of…

Optics · Physics 2023-07-13 Weijie Dong , Xiaoxi Zhou , Xinyang Pan , Haitao Li , Gang Wang , Yadong Xu , Bo Hou

We report an experimental observation of the collision between a linear wave propagating in the anomalous dispersion region of an optical fiber and a dark soliton located in the normal dispersion region. This interaction results in the…

The stochastic motion in a nonhomogeneous medium with traps is studied and diffusion properties of that system are discussed. The particle is subjected to a stochastic stimulation obeying a general L\'evy stable statistics and experiences…

Statistical Mechanics · Physics 2015-06-11 Tomasz Srokowski

Providing efficient nonlinear optical frequency conversion is essential for numerous applications. Fundamentally, dispersion limits the efficiency of such processes through mismatch of the phase velocities and the group velocities of the…

Optics · Physics 2020-07-27 Georgiy Shoulga , Alon Bahabad

The diffusion process near low order synchro-betatron resonances driven by beam-beam interactions at a crossing angle is investigated. Macroscopic observables such as beam emittance, lifetime and beam profiles are calculated. These are…

Accelerator Physics · Physics 2015-06-05 Tanaji Sen

Transparent media exhibiting anomalous dispersion have been of considerable interest since Wang, Kuzmich, and Dogariu [Nature {\bf 406}, 277 (2000)] first observed light propagate with superluminal and negative group velocities without…

Quantum Physics · Physics 2011-02-01 James Owen Weatherall , Christopher P. Search

Gonz\'alez et al. (2003) have reported the discovery of an anomalous radiation component from ~ 1 -- 200 MeV in GRB 941017. This component varies independently of and contains > 3 times the energy found in the prompt ~ 50 keV -- 1 MeV…

Astrophysics · Physics 2009-11-10 C. D. Dermer , A. Atoyan

The reflection spectrum of a probe light in a -type three-level atomic system coupled by an off-resonant standing-wave is investigated experimentally and theoretically. We show that the maximum value of reflection coefficient occurs when…

Quantum Physics · Physics 2011-02-24 Hai-Tao Zhou , Miao-jun Guo , Da-Wei Wang , Jun-Xiang Zhang , Shi-Yao Zhu

A strong light pulse propagating in a nonlinear Kerr medium produces a change in the refractive index, which makes light travel at different speeds inside and outside the pulse. By tuning the pulse velocity, an analog black hole horizon can…

Optics · Physics 2013-03-19 Stefano Finazzi , Iacopo Carusotto

We study the causes of anomalous dispersion in Darcy-scale porous media characterized by spatially heterogeneous hydraulic properties. Spatial variability in hydraulic conductivity leads to spatial variability in the flow properties through…

Fluid Dynamics · Physics 2017-11-22 Alessandro Comolli , Marco Dentz

We study the propagation of a Laguerre-Gaussian (LG) beam through a dispersive atomic medium. We restrict ourselves to applying a weak probe field and three strong coupling fields to the medium, which leads to developing a four-level double…

Optics · Physics 2020-07-23 Zahra Amini Sabegh , Mohammad Mahmoudi

The problem of anomalous diffusion in the momentum space is considered on the basis of the appropriate probability transition function (PTF). New general equation for description of the diffusion of heavy particles in the gas of the light…

Statistical Mechanics · Physics 2015-05-13 S. A. Trigger

There is experimental and theoretical evidence that the broad rapidity distribution of net proton yield in central heavy-ion collisions at SPS energies could be a signal of non-equilibrium properties of the system. We show that the broad…

High Energy Physics - Phenomenology · Physics 2015-06-25 A. Lavagno

Angular dispersion can counterbalance normal group-velocity dispersion (GVD) that increases the wave-vector length in a dispersive medium. By tilting the wave vector, angular dispersion reduces the axial wave number in this case to match…

Optics · Physics 2022-02-03 Layton A. Hall , Ayman F. Abouraddy

We report on the time-resolved detection of the anomalous velocity, constituting charge carriers moving perpendicular to an electric driving field, in undoped GaAs quantum wells. For this we optically excite the quantum wells with…

Mesoscale and Nanoscale Physics · Physics 2015-12-23 Shekhar Priyadarshi , Klaus Pierz , Mark Bieler

Robust topological edge modes may evolve into complex-frequency modes when a physical system becomes non-Hermitian. We show that, while having negligible forward optical extinction cross section, a conjugate pair of such complex topological…

Mesoscale and Nanoscale Physics · Physics 2016-12-02 C. W. Ling , Ka Hei Choi , T. C. Mok , Z. Q. Zhang , Kin Hung Fung