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Slow light of an amplitude modulated Gaussian (AMG) pulse in cesium vapor is demonstrated and studied, as an appropriate amplitude modulation to a single pulse can expand its spectrum and thus increase the utilization efficiency of the…

Quantum Physics · Physics 2015-05-13 Wenzhuo Tang , Bin Luo , Yu Liu , Hong Guo

We show that atoms from wide velocity interval can be concurrently involved in Doppler-free two-photon resonant far from frequency degenerate four-wave mixing with the aid of auxiliary electromagnetic field. This gives rise to substantial…

Quantum Physics · Physics 2016-09-08 Alexander K. Popov , Alexander S. Bayev

Optical amplification is critical for optical signal transmission. While the emergence of erbium-doped fiber amplifiers has revolutionized optical communications in fiber-based systems, on-chip amplification remains essential for integrated…

We demonstrate superluminal light propagation using two frequency multiplexed pump beams to produce a gain doublet in a photorefractive crystal of Ce:BaTiO3. The two gain lines are obtained by two-wave mixing between a probe field and two…

Quantum Physics · Physics 2008-09-24 H. N. Yum , M. Salit , G. S. Pati , S. Tseng , P. R. Hemmer , M. S. Shahriar

We propose and experimentally demonstrate an optical pulse sampling method for photonic blind source separation. The photonic system processes and separates wideband signals based on the statistical information of the mixed signals and thus…

Signal Processing · Electrical Eng. & Systems 2021-07-23 Taichu Shi , Yang Qi , Weipeng Zhang , Paul R. Prucnal , Jie Li , Ben Wu

We study inelastic collisions of counter-propagating self-induced transparency solitons in a homogeneously broadened two-level medium. The energy of the pulse can be almost totally absorbed in the medium due to asymmetric collision with a…

Optics · Physics 2012-04-11 Denis Novitsky

Contemporary observational and theoretical studies on the temporal nature of microscopic measurements renewed the discussion about the fundamental constants, leading to the possibility of light speed variation and superluminal pulse…

General Physics · Physics 2007-05-23 R Assumpcao

We consider the simultaneous propagation of a pair of Raman-resonant, frequency-modulated (chirped) laser pulses in an optically thick medium, modeled by an ensemble of $\Lambda$-atoms. A self-organization ('matching`) effect is shown for…

Quantum Physics · Physics 2014-03-19 N. Sandor , G. Demeter , D. Dzsotjan , G. P. Djotyan

A setup to frequency-convert an arbitrary image encoded in the spatial profile of a probe field onto a signal field using four-wave mixing in a thermal atom vapor is proposed. The atomic motion is exploited to cancel diffraction of both…

Quantum Physics · Physics 2015-06-17 L. Zhang , J. Evers

Efficiency is a critical factor limiting the applications of nonlinear plasmonic devices. We show by theory and experiments that high efficiency four-wave mixing (FWM) is achieved in nanometer size plasmonic hotspots, which open up…

Optics · Physics 2020-06-16 Hui Yi , Xiaodan Wang , Tian Yang

Electromagnetic waves propagating in a layered superconductor with arbitrary momentum with respect to the main crystallographic directions display an unavoidable mixing between longitudinal and transverse degrees of freedom. Here we show…

Superconductivity · Physics 2024-06-14 Niccolò Sellati , Jacopo Fiore , Claudio Castellani , Lara Benfatto

We consider pulse propagation through a two component composite medium (metal inclusions in a dielectric host) with or without cavity mirrors. We show that a very thin slab of such a medium, under conditions of localized plasmon resonance,…

Optics · Physics 2009-11-13 M. Kulkarni , N. Seshadri , V. S. C. Manga Rao , S. Dutta Gupta

The propagation of a weak probe field in a laser-driven four-level atomic system is investigated. We choose mercury as our model system, where the probe transition is in the ultraviolet region. A high-resolution peak appears in the optical…

Quantum Physics · Physics 2009-11-13 M. Mahmoudi , M. Sahrai , J. Evers

A high-intensity laser pulse propagating through a medium triggers an ionization front that can accelerate and frequency-upshift the photons of a second pulse. The maximum upshift is ultimately limited by the accelerated photons outpacing…

Plasma Physics · Physics 2019-09-25 A. J. Howard , D. Turnbull , A. S. Davies , P. Franke , D. H. Froula , J. P. Palastro

We experimentally demonstrate a novel nonlinear effect in optical fibers: upconversion luminescence generation excited by multiphoton absorption of femtosecond infrared pulses. We directly estimate the average number of photons involved in…

Optics · Physics 2020-09-29 F. Mangini , M. Ferraro , M. Zitelli , A. Niang , A. Tonello , V. Couderc , S. Wabnitz

Pulse propagation is studied in an EIT medium with the control field having a periodically varying phase (chirp). Based both on numerical calculations and on an approximate approach neglecting absorption and nonadiabatic effects, it is…

Quantum Physics · Physics 2016-08-24 Andrzej Raczynski , Jaroslaw Zaremba , Sylwia Zielinska-Raczynska

In recent years it has become clear that the transport of excitons and charge carriers in molecular systems can be enhanced by coherent coupling with photons, giving rise to the formation of hybrid excitations known as polaritons. Such…

Materials Science · Physics 2023-01-19 M. Balasubrahmaniyam , Arie Simkovich , Adina Golombek , Guy Ankonina , Tal Schwartz

Using spectral hole-burning-based ultraslow group velocity in a dilute solid medium, we report enhanced photon echo efficiency three orders of magnitude higher than that in a nonslow light regime. The enhancement is due to exponentially…

Quantum Physics · Physics 2011-03-02 J. Hahn , B. S. Ham

Results of experimental pump-probe spectroscopy of a quantum dash optical amplifier biased at transparency are presented. Using strong pump pulses we observe a competition between free carrier absorption and two-photon induced stimulated…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Per Lunnemann , Sara Ek , Kresten Yvind , Rozenn Piron , Jesper Mørk

A recent paper showed how to construct a lens that focuses near field radiation and hence produce resolution unlimited by wavelength. The prescription requires lossless materials with negative refractive index: finite loss cuts off the…

Condensed Matter · Physics 2009-11-07 S. Anantha Ramakrishna , J. B. Pendry
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