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Related papers: Needle beams and structured space-time wavepackets

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Structured waves are ubiquitous for all areas of wave physics, both classical and quantum, where the wavefields are inhomogeneous and cannot be approximated by a single plane wave. Even the interference of two plane waves, or a single…

Slow light propagation is an important phenomenon in quantum optics. Here, we theoretically study the properties of slow light in a simple optomechanical system considering an effect of non-rotating wave approximation (NRWA) that was…

Quantum Physics · Physics 2021-02-23 Xiao-Bo Yan

We experimentally demonstrate temporal pumping of elastic waves in an electromechanical waveguide. An aluminum beam covered by an array of piezoelectric patches connected to shunt circuits with controllable resistances enables the spatial…

Software-defined metasurfaces (SDMs) comprise a dense topology of basic elements called meta-atoms, exerting the highest degree of control over surface currents among intelligent panel technologies. As such, they can transform impinging…

Emerging Technologies · Computer Science 2019-05-08 Christos Liaskos , Ageliki Tsioliaridou , Shuai Nie , Andreas Pitsillides , Sotiris Ioannidis , Ian Akyildiz

The next generation of cellular networks will exploit mmWave frequencies to dramatically increase the network capacity. The communication at such high frequencies, however, requires directionality to compensate the increase in propagation…

Networking and Internet Architecture · Computer Science 2019-11-11 Marco Giordani , Michele Polese , Arnab Roy , Douglas Castor , Michele Zorzi

We introduce stripe-like quasi-nondiffracting lattices that can be generated via spatial spectrum engineering. The complexity of the spatial shapes of such lattices and the distance of their almost diffractionless propagation depend on the…

Experiment, theory, and simulation are employed to understand the dispersion of colloidal particles in a periodic array of oscillating harmonic traps generated by optical tweezers. In the presence of trap oscillation, a non-monotonic and…

Soft Condensed Matter · Physics 2023-01-18 Joseph M. Barakat , Sho C. Takatori

A fully nonlinear, time-asymptotic theory of resonant particle trapping in large-amplitude quasi-parallel Alfven waves is presented. The effect of trapped particles on the nonlinear dynamics of quasi-stationary Alfvenic discontinuities and…

Plasma Physics · Physics 2007-05-23 M. V. Medvedev , P. H. Diamond , M. N. Rosenbluth , V. I. Shevchenko

Dispersive shock waves (DSWs) are expanding nonlinear wave trains that arise when dispersion regularizes a steepening front, a phenomenon observed in fluids, plasmas, optics, and superfluids. Here we report the first experimental…

Accelerator Physics · Physics 2025-10-23 H. McCright , I. G. Abel , I. Haber , P. G. O'Shea , B. L. Beaudoin

A theoretical investigation is made of acoustic wave propagation in a periodically stubbed waveguide. In general the waveguide segments and stubs are made of different materials. The acoustic wave in such a system has two independent…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 X. F. Wang , M. S. Kushwaha , P. Vasilopoulos

We demonstrate both theoretically and experimentally nonparaxial Mathieu and Weber accelerating beams, generalizing the concept of previously found accelerating beams. We show that such beams bend into large angles along circular,…

We present new theoretical foundations for unsupervised Spike-Timing-Dependent Plasticity (STDP) learning in spiking neural networks (SNNs). In contrast to empirical parameter search used in most previous works, we provide novel theoretical…

Computer Vision and Pattern Recognition · Computer Science 2022-02-23 Ali Safa , Ilja Ocket , André Bourdoux , Hichem Sahli , Francky Catthoor , Georges Gielen

In image segmentation, there is often more than one plausible solution for a given input. In medical imaging, for example, experts will often disagree about the exact location of object boundaries. Estimating this inherent uncertainty and…

Computer Vision and Pattern Recognition · Computer Science 2020-12-23 Miguel Monteiro , Loïc Le Folgoc , Daniel Coelho de Castro , Nick Pawlowski , Bernardo Marques , Konstantinos Kamnitsas , Mark van der Wilk , Ben Glocker

This article demonstrates the realization of an extraordinary beam splitter based on nonreciprocal and synchronized photonic transitions in obliquely illuminated space-time-modulated (STM) slabs which impart the coherent temporal frequency…

Optics · Physics 2019-02-06 Sajjad Taravati , Ahmed A. Kishk

An electron or electron-positron beam streaming through a plasma is notoriously prone to micro-instabilities. For a dilute ultrarelativistic infinite beam, the dominant instability is a mixed mode between longitudinal two-stream and…

The propagation and transmission of Bessel beams through nano-layered structures has been discussed recently. Within this framework we recognize the formation of unguided diffraction-free waves with the spot size approaching and…

Optics · Physics 2016-01-20 Carlos J. Zapata-Rodriguez

We report on the observation and quantitative assessment of self-trapped pulsating beams in a highly non-local nonlinear regime. The experiments were conducted in nematic liquid crystals and allow a meaningful comparison with the prediction…

Optics · Physics 2009-11-10 Claudio Conti , Marco Peccianti , Gaetano Assanto

We study the temporal evolution of speckle patterns in transmission of short wave pulses through a disordered waveguide. In the diffuse regime, the short-range spatial structure of speckles is the same as for continuous wave (cw)…

Disordered Systems and Neural Networks · Physics 2007-05-23 S. E. Skipetrov

We investigate wavelet-like localized solutions in nonlinear waveguides, enabled by complementary propagation constants embedded in domains of anomalous dispersion. They are carrier-envelope-phase stable and independent of fine details of…

Optics · Physics 2024-10-10 O. Melchert , A. Demircan

Huygens' metasurfaces have demonstrated almost arbitrary control over the shape of a scattered beam, however, its spatial profile is typically fixed at fabrication time. Dynamic reconfiguration of this beam profile with tunable elements…

Applied Physics · Physics 2018-12-04 Mingkai Liu , David A. Powell , Yair Zarate , Ilya V. Shadrivov
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