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Related papers: Pulsed light beams in vacuum with superluminal and…

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Propagation of ultrashort optical pulses in a dense resonant medium is considered in the semiclassical limit. In our analysis, we place emphasis on several main points. First, we study transformations of spectra in the process of pulse…

Optics · Physics 2011-07-20 Denis Novitsky

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

We present an electronic circuit which simulates wave propagation in dispersive media. The circuit is an array of phase shifter composed of operational amplifiers and can be described with a discretized version of one-dimensional wave…

Quantum Physics · Physics 2009-11-10 T. Nakanishi , K Sugiyama , M. Kitano

We describe a pulsed rotating supersonic beam source, evolved from an ancestral device [M. Gupta and D. Herschbach, J. Phys. Chem. A 105, 1626 (2001)]. The beam emerges from a nozzle near the tip of a hollow rotor which can be spun at…

Ultra-broadband hyperbolic Airy beams are experimentally realized and spatio-temporally characterized. Transmissive (refractive) and reflective cubic phase elements were used to impose a cubic phase on the input beam. Nondispersing beams…

Optics · Physics 2018-08-29 Andreas Valdmann , Peeter Piksarv , Heli Valtna-Lukner , Peeter Saari

Electromagnetically induced transparency in an optically thick, cold medium creates a unique system where pulse-propagation velocities may be orders of magnitude less than $c$ and optical nonlinearities become exceedingly large. As a…

Quantum Physics · Physics 2009-11-10 Danielle A. Braje , Vlatko Balic , G. Y. Yin , S. E. Harris

Although a plethora of techniques are now available for controlling the group velocity of an optical wave packet, there are very few options for creating accelerating or decelerating wave packets whose group velocity varies controllably…

Optics · Physics 2021-02-02 Murat Yessenov , Ayman F. Abouraddy

Powerful incoherent laser pulses can propagate in focusing Kerr media much longer distances than can coherent pulses, due to the fast phase mixing that prevents transverse filamentation. This distance is limited by 4-wave scattering, which…

Plasma Physics · Physics 2016-09-28 V. M. Malkin , N. J. Fisch

We analyze the propagation of fast-light pulses through a finite-length resonant gain medium both analytically and numerically. We find that intrinsic instabilities can be avoided in attaining a substantial peak advance with an ultra-short…

Quantum Physics · Physics 2007-05-23 B. D. Clader , Q-Han Park , J. H. Eberly

The speed of light in vacuum, $c$, is a fundamental constant of nature. Photons belonging to a structured beam of finite transverse size, generated by a spatial light modulator, have been observed to travel with a group velocity, $v_g$,…

Over the past 15 years, several groups have engineered media that are both strongly dispersive and roughly transparent for some finite bandwidth. Relationships and intuitive models that are satisfactory when it is reasonable to neglect…

Optics · Physics 2010-06-01 Douglas H. Bradshaw

We demonstrate that an ultrashort high intensity laser pulse can propagate for hundreds of Rayleigh ranges in a prepared neutral hydrogen channel by generating its own plasma waveguide as it propagates; the front of the pulse generates a…

Plasma Physics · Physics 2020-11-11 L. Feder , B. Miao , J. E. Shrock , A. Goffin , H. M. Milchberg

A remarkable phenomenon of superoscillations implies that electromagnetic waves can locally oscillate in space or time faster than the fastest spatial and temporal Fourier component of the entire function. This phenomenon allows to focus…

Optics · Physics 2025-04-18 Yijie Shen , Nikitas Papasimakis , Nikolay I. Zheludev

When a negative slope of the dispersion curve is encountered, the propagating light may be either 'fast light' or 'backward propagating'. We show that causality considerations select only one of which for each scenario, and demonstrate that…

Optics · Physics 2008-07-31 Eyal Feigenbaum , Noam Kaminski , Meir Orenstein

The present paper discusses certain special Gaussian beams that, thanks to some polynomial prefactors, have uniquely designed holes in the irradiance. Such holes, or rather tubes, can constitute potential valleys for negatively polarizable…

Optics · Physics 2025-02-13 Tomasz Radozycki

We present experimental evidence that light storage, i.e. the controlled release of a light pulse by an atomic sample dependent on the past presence of a writing pulse, is not restricted to small group velocity media but can also occur in a…

Atomic Physics · Physics 2009-11-11 A. Lezama , A. M. Akulshin , A. I. Sidorov , P. Hannaford

We theoretically investigate the response of optical phase conjugators to incident probe pulses. In the stable (sub-threshold) operating regime of an optical phase conjugator it is possible to transmit probe pulses with a superluminally…

Optics · Physics 2009-10-31 M. Blaauboer , A. G. Kofman , A. E. Kozhekin , G. Kurizki , D. Lenstra , A. Lodder

We investigate the spatio-temporal evolution of a Gaussian probe pulse propagating through a four-level $N$-type atomic medium. At two-photon resonance of probe-and control fields, weaker probe pulses may propagate through the medium with…

Quantum Physics · Physics 2015-09-01 Rajitha K. V. , Tarak N. Dey , Jörg Evers , Martin Kiffner

We compute the stationary profiles of a coherent beam of Bose condensed atoms propagating through a guide. Special emphasis is put on the effect of an obstacle present on the trajectory of the beam. The obstacle considered (such as a bend…

Condensed Matter · Physics 2009-11-07 P. Leboeuf , N. Pavloff

We investigate theoretically the formation of two-component light with superluminal group velocity in a medium controlled by four Raman pump fields. In such an optical scheme only a particular combination of the probe fields is coupled to…

Quantum Physics · Physics 2016-08-10 V. Kudriašov , J. Ruseckas , A. Mekys , A. Ekers , N. Bezuglov , G. Juzeliūnas