Results 41 to 50 of about 8,222 (253)

Energy backflow in a focal spot of the cylindrical vector beam [PDF]

Компьютерная оптика, 2018
Using Richards-Wolf formulae it is shown that a tightly focused azimuthally-radially polarized m-th order laser beam with an arbitrary apodization function produces a reverse energy flow in the focal plane (m=2).
Sergey Stafeev, Anton Nalimov, Victor Kotlyar   +2 more
doaj   +1 more source

Transverse intensity at the tight focus of a second-order cylindrical vector beam

Компьютерная оптика, 2021
In this paper, an effect of a reverse energy flow at the focus of a second-order cylindrical vector beam which passed through amplitude zone plate was investigated with a scanning near-field optical microscope.
E.S. Kozlova, S.S. Stafeev , S.A. Fomchenkov, V.V. Podlipnov, V.V. Kotlyar   +4 more
doaj   +1 more source

Focusing fractional-order cylindrical vector beams

Computer Optics, 2021
By numerically simulating the sharp focusing of fractional-order vector beams (0≤m≤1, with azimuthal polarization at m=1 and linear polarization at m=0), it is shown that the shape of the intensity distribution in the focal spot changes from elliptical (m=0) to round (m=0.5) and ends up being annular (m=1).
S.S. Stafeev, V.D. Zaitsev
openaire   +2 more sources

Slip Localization Intensification Mediated by Grain Boundary Sliding in a Polycrystalline Nickel‐Based Superalloy

Advanced Engineering Materials, EarlyView.
The temperature dependence of fatigue behavior in nickel‐based superalloys is investigated through high‐resolution measurements of plastic localization. While increasing temperature reduces localization and enhances fatigue performance in René 88DT, Inconel 718 exhibits a sharp degradation at intermediate temperature due to intensified slip ...
M. Calvat, D. Anjaria, I. Woo, C. Bean, D. Texier, J. C. Stinville   +5 more
wiley   +1 more source

Fatigue Crack Initiation and Growth in Nanocrystalline Ni at Multiple Length‐Scales

Advanced Engineering Materials, EarlyView.
Overview of miniaturized in situ SEM fatigue setup and resultant fatigue crack growth data for nanocrystalline Ni. The presented study focuses on the analysis of fatigue crack growth rate (FCGR) in focused ion beam‐notched microcantilevers prepared from nanocrystalline (NC) Ni as a model material.
Igor Moravcik, Alexander Jelinek, Markus Alfreider, Jutta Luksch, Anton Hohenwarter, Florian Schaefer, Christian Motz, Daniel Kiener   +7 more
wiley   +1 more source

Influence of Si Content and Milling Duration on the Microstructure and Mechanical–Tribological Properties of AlCoCrFeNiSi High‐Entropy Alloys

Advanced Engineering Materials, EarlyView.
Si‐doped AlCoCrFeNi high‐entropy alloys are synthesized by mechanical alloying to reveal the effect of Si content and milling time on phase evolution, microstructural refinement, and tribological behavior. A transition from FCC to BCC structure, significant grain refinement, and enhanced hardness and wear resistance are achieved, with the 4 at% Si ...
Mustafa Okumuş, Mehmet Emin Demir, Sercan Özpınar   +2 more
wiley   +1 more source

Exploring Curvature Effects in Direct‐Written 3D Curved Hollow Magnetic Nanoshells

Advanced Functional Materials, EarlyView.
Fabricated by a hybrid FEBID/CVD method, 3D PtC/Co3Fe core–shell heterostructures with engineered curvature and shell thickness exhibit complex reversal modes with axially symmetric N'eel‐type domain walls. XMCD‐PEEM combined with full‐scale micromagnetic simulations reveal how curvature and thickness govern the domain wall energy landscape and shape ...
Oleksii M. Volkov, Fabrizio Porrati, Florian Kronast, Riccardo Hertel, Pavlo Makushko, Olha Bezsmertna, Alexander Kuprava, Mohamad‐Assaad Mawass, Sven Barth, Michael Huth, Denys Makarov   +10 more
wiley   +1 more source

A Non‐Reciprocal Architected Porous Medium

Advanced Functional Materials, EarlyView.
ABSTRACT In several fluid flow, energy‐dumping, and energy‐harvesting applications, a dominant flow direction or dominant resistance direction is desirable. In this study, we propose a simple modular geometry that doubles flow resistance in one direction relative to the opposite direction, while maintaining laminar viscous flow.
Clément Vezies, Pablo Zavattieri, Nicolás Silin   +2 more
wiley   +1 more source

Coating Artificial Spider Silk Fiber with Magnetic FeCo: An Effective Strategy for Creating a Flexible Magneto‐Responsive Material

Advanced Functional Materials, EarlyView.
An original method is presented for producing artificial spider silk fibers with magnetic and magnetomechanical responsiveness, which consists in coating them with a nanometer‐thick layer of FeCo alloy by sputtering deposition. The challenge of combining organic materials and inorganic magnetic nanostructures is addressed, thus taking a step forward ...
Filippo Lanaro, Federico Spizzo, Gabriele Greco, Benjamin Schmuck, Anna Rising, Lucia Del Bianco   +5 more
wiley   +1 more source

Optical trapping and optical binding using cylindrical vector beams

Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali, 2011
We report on the use of cylindrical vector beams for optical manipulation of micron and sub-micron sized particles using the methods of a single-beam gradient force trap (optical tweezers) and an evanescent-field surface trap (optical binding).
S. E. Skelton, M. Sergides, R. Patel, E. Karczewska, O. M. Marago', P. H. Jones   +5 more
doaj   +1 more source