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Related papers: Diffraction-free space-time beams

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Optical fields with rich and well-developed spatio-temporal structure, including ultra-short structured light pulses, are essentially non-monochromatic and contain a continuous spectrum of monochromatic constituents. However, some…

Optics · Physics 2024-04-12 Aleksandr Bekshaev

Polarization de-multiplexing and multiplexing by means of conical refraction is proposed to increase the channel capacity for free space optical communication applications. The proposed technique is based on the forward-backward optical…

Optics · Physics 2015-02-25 Alex Turpin , Yurii Loiko , Todor K. Kalkandjiev , Jordi Mompart

Photonic time-stretch overcomes the speed limitation of conventional digitizers, and enables the observation of non-repetitive and statistically rare phenomena that occur on short timescales. In most of the time-stretch applications, large…

Optics · Physics 2019-03-15 Liao Chen , Xin Dong , Ningning Yang , Lei Zhang , Xi Zhou , Zihui Lei , Chi Zhang , Xinliang Zhang

In a recent work [20], we predicted and experimentally validated a new physical mechanism for altering the propagation path of a monochromatic beam. Specifically, we showed that by properly tailoring the spatial distribution of the linear…

Optics · Physics 2023-05-24 J. M. Nichols , D. V. Nickel , G. K. Rohde , F. Bucholtz

Space-time (ST) wave packets are a class of pulsed optical beams whose spatio-temporal spectral structure results in propagation invariance, tunable group velocity, and fascinating refractive phenomena. Here, we investigate the refraction…

We propose a framework for designing coherent optical environments that enable versatile and dynamic optical manipulation. In contrast to conventional material-based near-field platforms, our approach employs a structured coherent light…

Optics · Physics 2025-10-07 Xiaoshu Zhao , Xu Yuan , Hongxia Zheng , Huajin Chen , Zhifang Lin

The instabilities arising in a one-dimensional beam sustained by the diffusive photorefractive nonlinearity in out-of-equilibrium ferroelectrics are theoretically and numerically investigated. In the "scale-free model", in striking contrast…

Optics · Physics 2012-01-19 Viola Folli , Eugenio DelRe , Claudio Conti

We report experimental observation and theoretical explanation of novel propagation regimes for optical beams in an artificial nonlinear material with outstanding photorefractive properties. Nondiffractive beams, which keep their shapes…

"Space-time" (ST) wave packets constitute a broad class of pulsed optical fields that are rigidly transported in linear media without diffraction or dispersion, and are therefore propagation-invariant in absence of optical nonlinearities or…

The propagation dynamics of two-dimensional (2D) ring-Airy beams is studied in the framework of the fractional Schr\"{o}dinger equation, which includes saturable or cubic self-focusing or defocusing nonlinearity and L\'{e}vy index ((LI)…

Optics · Physics 2022-12-16 Pengfei Li , Yanzhu Wei , Boris A. Malomed , Dumitru Mihalache

The change of the effective dimension of spacetime with the probed scale is a universal phenomenon shared by independent models of quantum gravity. Using tools of probability theory and multifractal geometry, we show how dimensional flow is…

High Energy Physics - Theory · Physics 2012-08-16 Gianluca Calcagni

Light can be confined transversely and delivered axially in a waveguide. However, waveguides are lossy static structures whose modal characteristics are fundamentally determined by the boundary conditions, and thus cannot be readily changed…

Space-time modulation of refractive index can produce synthetically moving interfaces with arbitrary apparent velocities, including superluminal motion, offering new ways to control light in dynamic media. On the other hand, space-time wave…

Optics · Physics 2025-12-16 Zeki Hayran , John B. Pendry

We propose a novel theoretical framework to demonstrate vector beams whose degree of polarization does not change on atmospheric propagation. Inspired by the Fresnel equations, we derive the reflective and refractive field of vector beams…

We report the first demonstration of wrinkled membranes as a kind of optical focusing devices, which are low cost, light weight and flexible. Our device consists of concentric wrinkle rings on a gold-PDMS bilayer membrane, which converts…

Optics · Physics 2015-12-04 Ran Li , Hui Yi , Xiao Hu , Leng Chen , Guangsha Shi , Weimin Wang , Tian Yang

We study the propagation of structured optical scalar beams in a spacetime background parameterized by a second-rank symmetric tensor. An analytic expression for the Green's function in a cylindrical coordinate system is obtained for…

Optics · Physics 2022-10-28 C. A. Escobar , A. Martín-Ruiz , M. Mondragón , R. Jáuregui

Space-time structuring of light - where spatial and temporal degrees of freedom are deliberately coupled and controlled - is an emerging area of optics that enables novel configurations of electromagnetic fields. Of particular importance…

Time-varying photonic systems open new possibilities for controlling light, enabling photonic time crystals, time reflection and refraction, frequency conversion, synthetic gauge fields, optical nonreciprocity, among others. These effects…

Optics · Physics 2026-01-27 Zeki Hayran , John B. Pendry , Prasad P. Iyer , Francesco Monticone

In this letter, we demonstrate a novel diffraction-free Bloch surface wave (DF-BSW) sustained on all-dielectric multilayers that does not diffract after being passed through three obstacles or across a single mode fiber. It can propagate in…

The propagation distance of a pulsed beam in free space is ultimately limited by diffraction and space-time coupling. "Space-time" (ST) wave packets are pulsed beams endowed with tight spatio-temporal spectral correlations that render them…

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