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Conventional surface-relief gratings are inefficient at deflecting normally-incident light by large angles. This constrains their use in many applications and limits the overall efficiency of any optical instrument integrating gratings.…

Optics · Physics 2021-11-19 Ashutosh Patri , Stephane Kena-Cohen , Christophe Caloz

The theory of turbulent photon filamentation in lasers with high Fresnel numbers is presented. A survey of experimental observations of turbulent filamentation is given. Theoretical description is based on the method of eliminating field…

Statistical Mechanics · Physics 2007-05-23 V. I. Yukalov

We present the experimental observation of the superlensing effect in a slab of a one-dimensional photonic crystal made of tilted dielectric elements. We show that this flat lens can achieve subwavelength resolution in different frequency…

Optics · Physics 2015-05-13 Salvatore Savo , Emiliano Di Gennaro , Antonello Andreone

Periodic photonic structures enable precise control over the light-matter interaction through band structure engineering. Certain lattice geometries exhibit dispersionless flat bands, characterized by vanishing group velocity and diverging…

Gravitational lensing allows us to probe the structure of matter on a broad range of astronomical scales, and as light from a distant source traverses an intervening galaxy, compact matter such as planets, stars, and black holes act as…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-09 Hugh Garsden , Geraint F. Lewis

Linear birefringence, as implemented in wave plates, is a natural way to control the state of polarization of light. We report on a general method for designing miniature planar wave plates using surface plasmons. The resonant optical…

Optics · Physics 2015-05-18 Aurelien Drezet , Cyriaque Genet , Thomas W. Ebbesen

This paper presents the results of a Fresnel Interferometric Array testbed. This new concept of imager involves diffraction focussing by a thin foil, in which many thousands of punched subapertures form a pattern related to a Fresnel zone…

Astrophysics · Physics 2008-08-07 Denis Serre , Laurent Koechlin , Paul Deba

Despite the recent advances in augmented reality (AR), which has shown the potential to significantly impact on our daily lives by offering a new way to manipulate and interact with virtual information, minimizing visual discomfort due to…

An aerodynamic lens injector was developed specifically for the needs of single-particle diffractive imaging experiments at free-electron lasers. Its design allows for quick changes of injector geometries and focusing properties in order to…

Bacteria light harvesters are interpreted as Vicsek fractal, based upon their morphology, even though such fractals contain only one, or perhaps two, generations. After using fractal dimensions to describe the geometry, we progress to use…

Optics · Physics 2020-09-04 Julian Juhi-Lian Ting

A microwave lens with highly reduced reflectance, as compared to conventional dielectric lenses, is proposed. The lens is based on two-dimensional or three-dimensional transmission-line networks that can be designed to have an effective…

Optics · Physics 2009-11-13 Pekka Alitalo , Olli Luukkonen , Joni Vehmas , Sergei Tretyakov

The 4f lens system is a standard Fourier-optics building block for angular control in optical platforms such as spatial light modulators, imaging systems, and data storage devices. This work presents the first nanoscale implementation of an…

Optics · Physics 2025-09-09 Mahmoud A. A. Abouelatta , Karim Achouri

To effectively apply passive speckle reduction methods, it is essential to use an illumination system that maximally exploits the non-ideal temporal coherence and angular diversity (spatial coherence reduction) of laser light. This study…

Optics · Physics 2025-04-28 A. Lapchuk , O. Prygun , D. Manko , I. Gorbov , Y. Morozov

Every signal propagating through the universe is diffracted by the gravitational fields of intervening objects, aka gravitational lenses. Diffraction is most efficient when caused by compact lenses, which invariably produce additional…

General Relativity and Quantum Cosmology · Physics 2024-04-29 Miguel Zumalacárregui

Diffractive neural network (DNN), which can perform machine learning tasks based on the light propagation and diffraction, has recently emerged as a promising optical computing paradigm due to its high parallel processing speed and low…

Optics · Physics 2026-01-27 Yudong Tian , Haifeng Xu , Yuqing Liu , Xiangyu Zhao , Jierong Cheng , Chongzhao Wu

While many unsupervised learning models focus on one family of tasks, either generative or discriminative, we explore the possibility of a unified representation learner: a model which addresses both families of tasks simultaneously. We…

Computer Vision and Pattern Recognition · Computer Science 2024-09-25 Soumik Mukhopadhyay , Matthew Gwilliam , Yosuke Yamaguchi , Vatsal Agarwal , Namitha Padmanabhan , Archana Swaminathan , Tianyi Zhou , Jun Ohya , Abhinav Shrivastava

In this research, we report the experimental evidence of the directional Fano resonances at the scattering of a plane, linearly polarized electromagnetic wave by a homogeneous dielectric sphere with high refractive index and low losses. We…

The scientific community has witnessed tremendous expansion of research on layered (i.e. two-dimensional, 2D) materials, with increasing recent focus on applications to photonics. Layered materials are particularly exciting for manipulating…

Materials Science · Physics 2020-11-17 Akshay Singh , Seong Soon Jo , Yifei Li , Changming Wu , Mo Li , R. Jaramillo

Most of the physically based techniques for rendering translucent objects use the diffusion theory of light scattering in turbid media. The widely used dipole diffusion model (Jensen et al. 2001) applies the diffusion-theory formula derived…

Graphics · Computer Science 2010-11-16 Konstantin Kolchin

We predict new phenomena, such as soliton steering and soliton fission, in optical lattices that fade away exponentially along the propagation direction. Such lattices, featuring tunable decay rates, arise in photorefractive crystals in the…

Optics · Physics 2009-11-11 Yaroslav V. Kartashov , Victor A. Vysloukh , Lluis Torner