Results 81 to 90 of about 1,705,952 (334)
Defect Analysis of the β– to γ–Ga2O3 Phase Transition
Advanced Functional Materials, EarlyView.The role of defects at all the relevant stages of the β$\beta$‐ to γ$\gamma$‐Ga2O3 polymorph transition is investigated using a multi method approach. The positron annihilation spectroscopy based results show that the defect density decreases after the transition, and that changes in defect configuration within the γ phase occur with increasing ...
Umutcan Bektas +9 more
wiley +1 more source
Orbital angular momentum beam instabilities in engineered nonlinear colloidal media
, 2017 In this letter, we experimentally demonstrate the evolution of the optical vortex beams of different topological charges propagating in engineered nano-colloidal suspension of negative polarizability with saturable nonlinearities.
Johnson, Eric +5 more
core +1 more source
Optics Express, 2020 Coherent beam combining (CBC) technology has distinct advantages in generating high power vortex beam. In this paper, a circularly arranged coherent beam array (CBA) with discrete vortex phases is constructed to generate vortex beams.
Tao Yu, H. Xia, Wenke Xie, Yiming Peng
semanticscholar +1 more source
Dielectric cross-shaped-resonator-based metasurface for vortex beam generation at mid-IR and THz wavelengths [PDF]
Nanophotonics, 2019 Metasurfaces are engineered thin surfaces comprising two-dimensional (2D) arrays of sub-wavelength-spaced and sub-wavelength-sized resonators. Metasurfaces can locally manipulate the amplitude, phase, and polarization of light with high spatial ...
Raghu Dharmavarapu +9 more
semanticscholar +1 more source
Clean‐Limit 2D Superconductivity in a Thick Exfoliated Kagome Film
Advanced Functional Materials, EarlyView.This study reports clean‐limit 2D superconductivity in a thick kagome system, analogous to the 3D case. It observes a drop in superfluid stiffness near the superconducting transition and a cusp‐like feature in the angular dependence of the upper critical field.
Fei Sun +3 more
wiley +1 more source
Polarization multiplexing and bifocal optical vortex metalens
Results in Physics, 2020 In this article, we demonstrate several optical vortex metalens (OVMs) based on the Pancharatnam–Berry (PB) geometric phase concept utilizing silicon nanobricks.
Wei Wang +4 more
doaj +1 more source
, 2011 The propagation of electron beams carrying angular momentum in crystals is studied using a multislice approach for the model system Fe. It is found that the vortex beam is distorted strongly due to elastic scattering.
Löffler, Stefan, Schattschneider, Peter
core +2 more sources
Vortex evolution in parametric wave mixing [PDF]
, 1999 We investigate the evolution of vortex wave front dislocations in multiple-wave second-harmonic generation processes in quadratic nonlinear media. Vortices nested in finite-size host beams are shown to nucleate and to annihilate in pairs, and to move ...
Molina Terriza, Gabriel +2 more
core +2 more sources
Ultrafast generation and control of an electron vortex beam via chiral plasmonic near fields [PDF]
Nature Materials, 2018 Vortex-carrying matter waves, such as chiral electron beams, are of significant interest in both applied and fundamental science. Continuous-wave electron vortex beams are commonly prepared via passive phase masks imprinting a transverse phase modulation
G. Vanacore +14 more
semanticscholar +1 more source
Optical vortex braiding with Bessel beams
Optics Letters, 2020 We propose the braiding of optical vortices in a laser beam with more than 2 π rotation by superposing Bessel modes with a plane wave. We experimentally demonstrate this by using a Bessel–Gaussian beam and a coaxial Gaussian, and we present measurements of three complete braids. The amount of braiding is fundamentally limited only
Andrew A. Voitiv +3 more
openaire +3 more sources