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Related papers: Pushing the limits of negative group velocity

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We show that Coherent Population Oscillations effect allows to burn a narrow spectral hole (26Hz) within the homogeneous absorption line of the optical transition of an Erbium ion-doped crystal. The large dispersion of the index of…

We present a simple electronic circuit which produces negative group delays for base-band pulses. When a band-limited pulse is applied as the input, a forwarded pulse appears at the output. The negative group delays in lumped systems share…

Quantum Physics · Physics 2009-11-07 T. Nakanishi , K. Sugiyama , M. Kitano

We show that short pulses propagating in zero-gap periodic systems can be reversed with 100% efficiency by using weak non-adiabatic tuning of the wave velocity at time-scales that can be much slower than the period. Unlike previous schemes,…

Optics · Physics 2015-05-28 Yonatan Sivan , John B. Pendry

We investigate coherent propagation through a large optical density Tm$^{3+}$:YAG crystal. Using an ultra-stable laser, fiber filtering and site selection, we investigate the transmitted pulse temporal profile. The plane wave condition is…

Quantum Physics · Physics 2011-06-15 J. Ruggiero , T. Chanelière , J. -L. Le Gouët

The propagation of a weak probe field in a four-level N-type quantum system in the presence of spontaneously generated coherence (SGC) is theoretically investigated. The optical properties of the system are studied and it is shown that the…

Atomic and Molecular Clusters · Physics 2013-03-05 Lida Ebrahimi Zohravi , Majid Abedi , Mohammad Mahmoudi

We demonstrate a remarkably effective single-stage compression technique for ultrafast pulses in the visible electromagnetic spectrum using second-harmonic pulses at 515 nmderived from a 1030 nm Yb-based femtosecond regenerative amplifier.…

More than 4 orders of magnitude of cavity-linewidth narrowing in a rare-earth-ion-doped crystal cavity, emanating from strong intracavity dispersion caused by off-resonant interaction with dopant ions, is demonstrated. The dispersion…

Quantum Physics · Physics 2015-07-07 Mahmood Sabooni , Qian Li , Lars Rippe , R. Krishna Mohan , Stefan Kroll

Reflectionless potentials (RPs) represent a class of potentials that offer total transmission in the context of one dimensional scattering. Optical realization of RPs in stratified medium can exhibit broadband omnidirectional antireflection…

We have analyzed the transmission properties of pulses through one-dimensional periodic structures in order to systematically explore the best conditions to achieve the maximum delay with the minimum possible distortion. In the absence of…

Optics · Physics 2015-06-03 O. del Barco , M. Ortuño

Electron acceleration has been optimized based on 3D PIC simulations of a short laser pulse interacting with low-density plasma targets to find the pulse propagation regime that maximizes the charge of high-energy electron bunches. This…

Plasma Physics · Physics 2020-01-08 M. G. Lobok , A. V. Brantov , V. Yu. Bychenkov

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

Valley photonic crystal is one type of photonic topological insulator, whose realization only needs P-symmetry breaking. The domain wall between two valley-contrasting photonic crystals support robust edge states which can wrap around sharp…

Applied Physics · Physics 2025-01-16 Fu-Long Shi , Yuan Cao , Xiao-Dong Chen , Jian-Wei Liu , Wen-Jie Chen , Min Chen , Jian-Wen Dong

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

Electromagnetic pulses with tilted pulse fronts are instrumental in enhancing the efficiency of many light-matter interaction processes, with prominent examples including terahertz generation by optical rectification, dielectric laser…

Optics · Physics 2019-03-05 Liang Jie Wong , Ido Kaminer

In this article, we experimentally demonstrate a new way of controlling the group velocity of an optical pulse by using a combination of spectral hole burning, slow light effect and linear Stark effect in a rare-earth-ion-doped crystal. The…

Optics · Physics 2017-03-15 Qian Li , Adam Kinos , Axel Thuresson , Lars Rippe , Stefan Kröll

Reconfigurable intelligent surface (RIS) as a smart reflector is revolutionizing research for next-generation wireless communications. Complementing this is a concept of using RIS as an efficient propagation medium for potentially superior…

Signal Processing · Electrical Eng. & Systems 2023-08-04 Z. Chu , K. F. Tong , K. K. Wong , C. B. Chae , C. H. Chan

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

We study optical pulse propagation through a hollow-core fiber filled with a radially inhomogeneous cloud of cold atoms. A co-propagating control field establishes electromagnetically induced transparency. In analogy to a graded index…

Atomic Physics · Physics 2019-07-31 Roman Sulzbach , Thorsten Peters , Reinhold Walser

Many fundamental processes of structural changes at surfaces occur on a pico- or femtosecond time scale. In order to study such ultra-fast processes, we have combined modern surface science techniques with fs-laser pulses in a pump-probe…

Mesoscale and Nanoscale Physics · Physics 2023-12-01 Michael Horn von Hoegen

We study the effect of the chirped laser pulse on the transmission and associated ion acceleration by the sub-wavelength target. In the chirped laser pulses, the pulse frequency has a temporal variation about its fundamental frequency,…

Plasma Physics · Physics 2018-11-06 Shivani Choudhary , Amol R. Holkundkar
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