Publications associées à Laser scanning

Transfer learning application of self-supervised learning in ARPES

There is a growing recognition that electronic band structure is a local property of materials and devices, and there is steep growth in capabilities to collect the relevant data. New photon sources, from small-laboratory-based lasers to free electron lase ...

IOP Publishing Ltd2023

Third-harmonic generation monitoring of femtosecond-laser-induced in-volume functional modifications

Christian Enz, Yves Bellouard, Assim Boukhayma, Andrea Kraxner, Olivier Bernard

During the last two decades, ultrafast in-volume laser-based processing of transparent materials has emerged as a key 3D-printing method for manufacturing a variety of complex integrated photonic devices and micro-parts. Yet, identifying suitable laser pro ...

2023

Tailored deformation behavior of 304L stainless steel through control of the crystallographic texture with laser-powder bed fusion

Roland Logé, Christian Leinenbach, Markus Strobl, Efthymios Polatidis

Laser-powder bed fusion (L-PBF) has gained significant research interest, not only for its profound advantage of producing near-net shape complex geometries of metallic parts, but also for the possibility of producing tailored microstructures. Here we expl ...

ELSEVIER SCI LTD2022

Dual chirped microcomb based parallel ranging at megapixel-line rates

Tobias Kippenberg, Junqiu Liu, Maxim Karpov, Anton Lukashchuk

Photonic integrated systems can be harnessed for fast and efficient optical telecommunication and metrology technologies. Here the authors develop a dual-soliton microcomb technique for massively parallel coherent laser ranging that requires only a single ...

Nature Portfolio2022

Creating and controlling exceptional points of non-Hermitian Hamiltonians via homodyne Lindbladian invariance

Fabrizio Minganti

The exceptional points (EPs) of non-Hermitian Hamiltonians (NHHs) are spectral degeneracies associated with coalescing eigenvalues and eigenvectors, which are associated with remarkable dynamical properties. These EPs can be generated experimentally in ope ...

AMER PHYSICAL SOC2022

Additive manufacturing of a precious bulk metallic glass

Roland Logé, Jamasp Jhabvala, Güven Kurtuldu, Antonia Neels, Navid Sohrabi, Annapaola Parrilli

For the first time, a high-density amorphous and crack-free bulk metallic glass (BMG) based on a precious metal (PdCuNiP) was produced via additive manufacturing (AM). Laser powder-bed fusion (LPBF) was used for the fabrication of the samples, and led to a ...

2021

Design-to-Fabrication Workflow for Raw-Sawn-Timber using Joinery Solver

Petras Vestartas

Currently, the Swiss timber industry in mountain areas largely exports unprocessed lumber and imports finished timber products due to the lack of digital tools. By using new digital design-to-production workflows, it is possible to investigate new building ...

EPFL2021

Laser engraving device for multiple laser beams

Andreas Schueler, Luc Burnier

The present invention concerns a laser engraving device (1) for engraving a target surface (17). The laser engraving device (1) comprises: a beam splitter (7) for dividing a processing laser beam (25) into a plurality of engraving laser beams (27); a first ...

2020

Operando X-ray diffraction during laser 3D printing: from machine design to experiments and computer simulations

Samy Hocine

The importance of additive manufacturing, also known as 3D printing, has grown exponentially in the recent years thanks to its high flexibility to manufacture intricate parts. This process can be divided into many different sub-categories, depending on the ...

EPFL2020

SCALAR: Simultaneous Calibration of 2-D Laser and Robot Kinematic Parameters Using Planarity and Distance Constraints

Teguh Santoso Lembono

In this paper, we propose SCALAR, a calibration method to simultaneously calibrate the kinematic parameters of a 6-DoF robot and the extrinsic parameters of a 2-D laser range finder (LRF) attached to the robot's flange. The calibration setup requires only ...

2019

ULTRASTABLE LASER SYSTEM FOR SPECTROSCOPY OF THE 1.14 mu m INNER-SHELL CLOCK TRANSITION IN Tm AND ITS ABSOLUTE FREQUENCY MEASUREMENT

Sergey Fedorov

We characterize a 1.14 mu m ultrastable semiconductor laser system for precision spectroscopy of Tm inner-shell clock transition using a frequency comb. We stabilize both the repetition and the carrier-envelope offset frequencies of a commercial Ti : sapph ...

SPRINGER2019

A 1.5-W frequency-doubled semiconductor disk laser tunable over 40 nm at around 745 nm

Elyahou Kapon, Vladimir Iakovlev, Alexei Sirbu

We report on a semiconductor disk laser emitting 1.5 W of output power at the wavelength of 745 nm via intracavity frequency doubling. The high power level and the >40 nm tuning range make the laser a promising tool for medical treatments that rely on phot ...

Spie-Int Soc Optical Engineering2016

Study and Modelling of the Melt Pool Dynamics during Selective Laser Sintering and Melting

Tatiana Polivnikova

Selective laser sintering (SLS) and Selective Laser Melting (SLM) are parent layer manufacturing processes that allow generating complex 3D parts by consolidating layers of powder material on top of each other. Consolidation is obtained by processing the s ...

EPFL2015

High-precision x-ray FEL pulse arrival time measurements at SACLA by a THz streak camera with Xe clusters

Leonid Rivkin, Christoph Peter Hauri, Rasmus Ischebeck, Ishkhan Gorgisyan, Junqiu Liu

The accurate measurement of the arrival time of a hard X-ray free electron laser (FEL) pulse with respect to a laser is of utmost importance for pump-probe experiments proposed or carried out at FEL facilities around the world. This manuscript presents the ...

Optical Society of America2014

Spectral cola or how to turn green laser light red

Thibaud Humair, Xavier François Mettan, Csaba Forro

A green laser pointer shone through a glass of cola will appear red when looking from above the glass. Lowering the laser so that it is deeper in the cola, the colour will vary from orange to deep red. Fluorescence and absorption spectra were recorded cons ...

Iop Publishing Ltd2014

Nanostructuring and lattice dynamics of materials by femtosecond lasers

Ahmad Odeh

Physically, the colour of an object is a complex result of its intrinsic surface properties, its transmission properties and its emission properties, all of which contribute to the mix of wavelengths in the light leaving the surface of the object. Structur ...

EPFL2013

Analysis and Control of Optical Modes in VCSELs and VCSEL-Arrays

Elodie Lamothe

In this thesis, we studied the modal structure and the polarization of the optical field emitted by vertical-cavity surface-emitting lasers (VCSELs) emitting in the short- and long-wavelength domains (0.9-1.3μm). Our study concerns two types of components: ...

EPFL2013

Design of a miniature laser scanning head for high-bandwidth, low-amplitude beam steering

Yves Bellouard, Reymond Clavel

In laser micro-manufacturing, one of the challenges is to achieve fast scanning speed for fast fabrication of complex 3D microstructures. For microstructures with nanoscale features, it is often desirable to steer laser beams from a few microns to a few te ...

2012

Application of Adaptive Optics to Focusing and Imaging

Daniel Iwaniuk

Adaptive optics is used to abate aberrations with a wavefront correction. It is widely used in astronomy and is starting to expand into applications of laser focusing and imaging with high numerical apertures, e.g. microscopy. The physical background of fo ...

EPFL2012

An innovative method to build support structures with a pulsed laser in the selective laser melting process

Rémy Glardon, Eric Boillat, Jamasp Jhabvala, Cédric André

In selective laser melting machines, continuous laser are usually used to melt the powder. The support structures, which are inevitable when dealing with elaborated pieces, necessitate a complex design by CAD in order to be easily removed. This paper propo ...

Springer-Verlag2012