English
Related papers

Related papers: Generalized axicon-based generation of nondiffract…

200 papers

General properties of linear propagation of discretized light in homogeneous and curved waveguide arrays are comprehensively investigated and compared to those of paraxial diffraction in continuous media. In particular, general laws…

Optics · Physics 2015-05-14 S. Longhi

Extremely anisotropic metal-dielectric multilayer metamaterials are designed to have the effective permittivity tensor of a transverse component (parallel to the interfaces of the multilayer) with zero real part and a longitudinal component…

Optics · Physics 2015-06-23 Lei Sun , Xiaodong Yang , Wei Wang , Jie Gao

Accelerator-based light sources such as storage rings and free-electron lasers use relativistic electron beams to produce intense radiation over a wide spectral range for fundamental research in physics, chemistry, materials science,…

Accelerator Physics · Physics 2015-06-19 Erik Hemsing , Gennady Stupakov , Dao Xiang , Alexander Zholents

Diffractionless propagation of optical beams through atomic vapors is investigated. The atoms in the vapor are operated in a three-level Raman configuration. A suitably chosen control beam couples to one of the transitions, and thereby…

Quantum Physics · Physics 2015-05-30 T. N. Dey , J. Evers

Diffraction-free optical beams propagate freely without change in shape and scale. Monochromatic beams that avoid diffractive spreading require two-dimensional transverse profiles, and there are no corresponding solutions for profiles…

Optics · Physics 2017-11-02 H. Esat Kondakci , Ayman F. Abouraddy

We suggest a method to generate coherent short pulses by generating a frequency comb using lasing without inversion in the transient regime. We use a universal method to study the propagation of a pulse in various spectral regions through…

New techniques for the optical generation of plasma waveguides -- optical fibres for ultra-intense light pulses -- have become vital to the advancement of multi-GeV laser wakefield acceleration. Here, we demonstrate the fabrication and…

Plasma Physics · Physics 2025-03-04 N. Tripathi , B. Miao , A. Sloss , E. Rockafellow , J. E. Shrock , S. W. Hancock , H. M. Milchberg

We propose a simple method for the detection of Bessel beams with arbitrary radial and azimuthal indices, and then demonstrate it in an all-digital setup with a spatial light modulator. We confirm that the fidelity of the detection method…

Pushing the limits of precision and reproducibility in ultrafast laser-based nanostructuring requires detailed control over the properties of the illumination. Most traditional methods of laser-based manufacturing rely on the simplicity of…

Optics · Physics 2023-06-13 Camilo Florian , Xiaohan Du , Craig B. Arnold

We show that in addition to well known Bessel, Hermite-Gauss, and Laguerre-Gauss beams of electromagnetic radiation, one may also construct exponential beams. These beams are characterized by a fall-off in the transverse direction described…

Optics · Physics 2009-11-13 Iwo Bialynicki-Birula , Zofia Bialynicka-Birula

We theoretically investigate droplet quasi-Bessel beams for different shapes of the round-tip axicon. Exact solutions for the Fresnel diffraction integrals describing the axial distribution of the electric field amplitude behind the axicon…

Optics · Physics 2022-09-07 V. Yu. Mylnikov , G. S. Sokolovskii

We introduce a novel and simple modulation technique to tailor optical beams with a customized amount of orbital angular momentum (OAM). The technique is based on the modulation of the angular spectrum of a seed beam, which allows us to…

Bessel beams are becoming a very useful tool in many areas of optics and photonics, because of the invariance of their intensity profile over an extended propagation range. Finite-Difference-Time-Domain (FDTD) approach is widely used for…

Optics · Physics 2021-02-26 Kazem Ardaneh , Remo Giust , Benoit Morel , Francois Courvoisier

Flat-top beam, known for its ability to generate a consistently even irradiation area, holds vast utility in many fields of scientific and industrial applications. In this paper, a reflective laser beam shaping method based on two…

Optics · Physics 2024-05-16 Zhihao Chen , Xiaonan Ning , Jiucheng Chen , Jianfei Hua , Wei Lu

The primary axes of interest in image-generating diffusion models are image quality, the amount of variation in the results, and how well the results align with a given condition, e.g., a class label or a text prompt. The popular…

Computer Vision and Pattern Recognition · Computer Science 2024-12-20 Tero Karras , Miika Aittala , Tuomas Kynkäänniemi , Jaakko Lehtinen , Timo Aila , Samuli Laine

Guiding unconditional diffusion models typically requires either retraining with conditional inputs or per-step gradient computations (e.g., classifier-based guidance), both of which incur substantial computational overhead. We present a…

Machine Learning · Computer Science 2026-02-13 Qingsong Wang , Mikhail Belkin , Yusu Wang

An alternative method to generate J0 Bessel beams with controlled spatial partial coherence properties is introduced. Far field diffraction from a discrete number of source points on an annular region is calculated. The average for…

In this paper, we develop a theoretical analysis to efficiently handle superpositions of waves with concentrated wavevector and frequency spectra, allowing an easy analytical description of fields with interesting transverse profiles.…

Quasi-Bessel beams produced by axiparabolas are increasingly used in high-intensity laser applications, yet their longitudinal profiles exhibit unwanted oscillations that limit their effectiveness. Here we identify the physical origin of…

The effects of coherence of quantum transitions and the interference of resonant nonlinear optical processes on the spectra of absorption, amplification, and nonlinear-optical generation are considered. The most favorable conditions are…

Quantum Physics · Physics 2007-05-23 A. K. Popov