Laser beams
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Dynamic Beam Switching by Liquid Crystal Tunable Dielectric Metasurfaces Open
Dynamic steering of laser beams by ultrathin optical metasurfaces is a significant research advance for possible applications in remote ranging and sensing. A unique platform for such important functionalities is offered by dielectric meta…
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Bessel Beam: Significance and Applications—A Progressive Review Open
Diffraction is a phenomenon related to the wave nature of light and arises when a propagating wave comes across an obstacle. Consequently, the wave can be transformed in amplitude or phase and diffraction occurs. Those parts of the wavefro…
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Physics and Measurement of Aero-Optical Effects: Past and Present Open
The field of aero-optics is devoted to the study of the effects of turbulent flow fields on laser beams projected from airborne laser systems. This article reviews the early and present periods of research in aero-optics. Both periods gene…
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Adversarial Laser Beam: Effective Physical-World Attack to DNNs in a Blink Open
Though it is well known that the performance of deep neural networks (DNNs) degrades under certain light conditions, there exists no study on the threats of light beams emitted from some physical source as adversarial attacker on DNNs in a…
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Vortex beams in turbulent media: review Open
The review covers publications concerned with propagation of laser beams through turbulent media described by the Kolmogorov theory and generalizations thereof to describe signal transmission in optical communications and detection systems…
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Bayesian Optimization of a Laser-Plasma Accelerator Open
Generating high-quality laser-plasma accelerated electron beams requires carefully balancing a plethora of physical effects and is therefore challenging-both conceptually and in experiments. Here, we use Bayesian optimization of key laser …
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Beam shaping technology and its application in metal laser additive manufacturing: A review Open
Laser additive manufacturing (AM) technology is widely applied in manufacturing critical components (e.g., rocket fuel nozzles, satellite antenna mounts and human implants, etc.) in automotive, medical, aerospace and other fields due to th…
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Spatial beam intensity shaping using phase masks on single-mode optical fibers fabricated by femtosecond direct laser writing Open
Submicrometer dielectric phase masks allow for the realization of the miniaturization of high-quality optical elements. In this Letter we demonstrate spatial intensity beam shaping using phase masks attached to optical single-mode fibers. …
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Single-tube on-beam quartz-enhanced photoacoustic spectroscopy Open
Quartz-enhanced photoacoustic spectroscopy (QEPAS) with a single-tube acoustic microresonator (AmR) inserted between the prongs of a custom quartz tuning fork (QTF) was developed, investigated, and optimized experimentally. Due to the high…
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Approaching the diffraction-limited, bandwidth-limited Petawatt Open
J-KAREN-P is a high-power laser facility aiming at the highest beam quality and irradiance for performing state-of-the art experiments at the frontier of modern science. Here we approached the physical limits of the beam quality: diffracti…
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Non-ideal axicon-generated Bessel beam application for intra-volume glass modification Open
The extended focal depth of Bessel beams is a very attracting property for glass cutting applications. However, Bessel beam generation with a non-ideal conical lens induces beam pattern distortions. We present our novel results on bulk mod…
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Optimal Beam Loading in a Laser-Plasma Accelerator Open
Applications of laser-plasma accelerators demand low energy spread beams and high-efficiency operation. Achieving both requires flattening the accelerating fields by controlled beam loading of the plasma wave. Here, we optimize the generat…
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Propagation of the power-exponent-phase vortex beam in paraxial ABCD system Open
The general analytical formula for the propagation of the power-exponent-phase vortex (PEPV) beam through a paraxial ABCD optical system is derived. On that basis the evolution of the intensity distribution of such a beam in free space and…
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Post-Processing of FDM 3D-Printed Polylactic Acid Parts by Laser Beam Cutting Open
In this paper, the post-processing of 3D-printed poly lactic acid (PLA) parts is investigated. Workpieces are manufactured by fused deposition modeling (FDM) 3D printing, while they may have defects in some areas such as edges. A post-proc…
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Spatio-spectral metrology at focus of ultrashort lasers: a phase-retrieval approach Open
This is an erratum on the manuscript entitled 'Spatio-spectral metrology at focus of ultrashort lasers: a phase-retrieval approach', by A. Borot and F. Quéré [Opt. Express26, 26444 (2018)].
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Coherent Beam Combination of Ultrafast Fiber Lasers Open
The performance of fiber laser systems has drastically increased over recent\ndecades, which has opened up new industrial and scientific applications for\nthis technology. However, currently a number of physical effects prevents\nfurther p…
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Freeform microlens array homogenizer for excimer laser beam shaping Open
We presented a novel technique to design microlens optical beam homogenizing system for excimer lasers. As a new approach by applying freeform surface microlens array, the homogenizer can yield somehow superior beam shaping results with la…
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Non-photochemical laser-induced nucleation Open
Non-photochemical laser-induced nucleation (NPLIN) is the formation of a new phase from a metastable phase by the action of light on matter. Using millijoule, nanosecond laser pulses at visible and near-infrared wavelengths, it is possible…
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Influence of Ring-Shaped Beam Profiles on Process Stability and Productivity in Laser-Based Powder Bed Fusion of AISI 316L Open
A major factor slowing down the establishment of additive manufacturing processes as production processes is insufficient reproducibility and productivity. Therefore, this work investigates the influence of ring-shaped beam profiles on pro…
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Efficient optical trapping with cylindrical vector beams Open
Radially and azimuthally polarized beams can create needle-like electric and magnetic fields under tight focusing conditions, respectively, and thus have been highly recommended for optical manipulation. There have been reports on the supe…
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Nonparaxial abruptly autofocusing beams Open
We study nonparaxial autofocusing beams with pre-engineered trajectories. We consider the case of linearly polarized electric optical beams and examine their focusing properties, such as contrast, beam width, and numerical aperture. Such b…
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Supercontinuum generation in a multi-plate medium Open
We analyze femtosecond supercontinuum generation in a distribution of thin solid plates to show that the distributed scheme inhibits processes leading to pulse breakup while allowing spectral expansion to proceed as desired. We introduce b…
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Single femtosecond laser beam induced nanogratings in transparent media - Mechanisms and applications Open
Single femtosecond laser beam induced nanograting structure in transparent media has attracted extensive attention in many fields of science and technology in the past decades. Considering the excellent physicochemical properties and promi…
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Microscopic Engine Powered by Critical Demixing Open
We experimentally demonstrate a microscopic engine powered by the local reversible demixing of a critical mixture. We show that, when an absorbing microsphere is optically trapped by a focused laser beam in a subcritical mixture, it is set…
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Bessel beams with spatial oscillating polarization Open
Bessel beams are widely used in optical metrology mainly because of their large Rayleigh range (focal length). Radial/azimuthal polarization of such beams is of interest in the fields of material processing, plasma absorption or communicat…
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Generation and propagation of a new kind of power-exponent-phase vortex beam Open
A general analytical formula for the propagation of the new kind of power-exponent-phase vortex beam through a paraxial ABCD optical system is derived. With two different calculation methods, the evolution of the intensity distribution and…
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Spatiotemporal light-beam compression from nonlinear mode coupling Open
We experimentally demonstrate simultaneous spatial and temporal compression in the propagation of light \npulses in multimode nonlinear optical fibers.We reveal that the spatial beam self-cleaning recently discovered in \ngraded-index mult…
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Tunable narrow-linewidth laser at 2 μm wavelength for gravitational wave detector research Open
We present and characterize a narrow-linewidth external-cavity diode laser at 2 μ m, and show that it represents a low-cost, high-performance alternative to fiber lasers for research into 2 μ m photonic technologies for next-generation gra…
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Efficient generation and tight focusing of radially polarized beam from linearly polarized beam with all-dielectric metasurface Open
We propose a single layer all-dielectric metasurface lens to simultaneously convert and focus an incident linear polarization into a radial beam with high efficiency and high numerical aperture (NA). It shows a better focusing property com…
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Experimental phase control of a 100 laser beam array with quasi-reinforcement learning of a neural network in an error reduction loop Open
An innovative scheme is proposed for the dynamic phase control of a laser beam array. It is based on a simple neural network included in a phase correction loop that predicts the complex field array from the intensity of the induced scatte…