Publications related to Laser engraving

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

In situ monitoring of femtosecond laser-induced modifications in dielectrics

Olivier Bernard

Over the last decades, the progress made in the generation of laser pulses shorter than a picosecond (10^-12 s) has allowed us to reach extreme optical power intensities exceeding 10^15 W cm^-2. This tremendous power has triggered an abundance of original ...

EPFL2023

Single-Layer Subwavelength Femtosecond-Laser-Induced Confined Nanocrystallization in Multistack Dielectrics

Yves Bellouard, Ruben Ricca

We demonstrate extreme laser-induced modification confinement in a stack of dielectric layers, along the optical axis, without the use of tight focusing. Specifically, we show that an aperiodic distribution of layer thicknesses can effectively lead to the ...

American Physical Society (APS)2023

On the interaction of femtosecond laser pulses with layered dielectric materials

Ruben Ricca

Materials properties are strictly dependent on their microstructure. The internal symmetries and the disposition of the constituting atoms of a material, which depend on its crystallographic structure, greatly affect its response to mechanical, electromagn ...

EPFL2023

Femtosecond laser-induced modifications and self-organization in complex glass systems

Gözden Torun

Ultrashort laser pulses, i.e., pulses emitted shorter than a picosecond, can tailor material properties by introducing permanent modifications locally in three dimensions. Remarkably, under a certain exposure condition, these modifications are accompanied ...

EPFL2023

A hybrid Selective Laser Sintering based process for the additive manufacturing of architectured composites

Erwan Philippe Guenier

Additive Manufacturing also commonly referred as 3D printing has been given a lot of interest lately. Market is growing exponentially and the aim for obtaining more complex and ready-to use parts is emerging. All the 3D printing processes consist in buildi ...

EPFL2023

Photonic assembly tunable via the pockels effect and method for use in frequency-modulated lidar

Tobias Kippenberg, Viacheslav Snigirev, Grigorii Likhachev

A photonic assembly, a laser setup comprising said photonic assembly and a method for performing frequency-modulated continuous-wave light detection and ranging using said laser setup are disclosed. The photonic assembly (1) comprises an active photonic ch ...

2023

Enhancement of Pressure-Sensitive Adhesive by CO2 Laser Treatment

Dario Floreano, Yegor Piskarev, Jun Shintake, Vivek Ramachandran, Michael Dickey, Jianhang Yang

Pressure-sensitive adhesives (PSAs) are polymeric films that can be adhered to and detached from surfaces without leaving residue. Researchers are looking to enhance the bond strength between PSAs and different substrates. It can be achieved by tuning PSA' ...

2022

Few-femtosecond resolved imaging of laser-driven nanoplasma expansion

Matthias Bucher, Christoph Bostedt

The free expansion of a planar plasma surface is a fundamental non-equilibrium process relevant for various fields but as-yet experimentally still difficult to capture. The significance of the associated spatiotemporal plasma motion ranges from astrophysic ...

IOP Publishing Ltd2022

Abnormal temperature dependent elastic properties of fused silica irradiated by ultrafast lasers

Yves Bellouard, Pieter Vlugter

Materials with thermal-invariant elastic properties are of interest for resonant device frequency and dimensional stability of precision devices. Here, we demonstrate that the temperature coefficient of elasticity (TCE) of amorphous silica can be locally r ...

2022

Effect of femtosecond laser-induced high pressure on fused silica polymorphism

Arunkrishnan Radhakrishnan

High-pressure studies in silica are of great interest to earth and planetary sciences. Highpressure phases are rarely found in nature as a result of shock events like meteorite impacts or volcanic events in nature. Recreating these phases remains a challen ...

EPFL2022

Thermal Modelling and Experimental Validation in the Perspective of Tool Steel Laser Polishing

Eric Boillat, Alexandre Masserey, Bastian Meylan

Laser polishing (LP) is a process that allows a significant reduction of the surface roughness of a metal workpiece via re-melting a shallow layer of material. However, the practical use of LP is limited due to the difficulty of satisfying the high surface ...

MDPI2022

NIR Fluorescence lifetime macroscopic imaging with a time-gated SPAD camera

Edoardo Charbon, Claudio Bruschini, Arin Can Ülkü

The performance of SwissSPAD2 (SS2), a large scale, widefield time-gated CMOS SPAD imager developed for fluorescence lifetime imaging, has recently been described in the context of visible range and fluorescence lifetime imaging microscopy (FLIM) of dyes w ...

SPIE-INT SOC OPTICAL ENGINEERING2022

Engineering Absorption for Foil Applications

Sebastian Mader

Light matter interactions such as extinction, reflection, and transmission can be described by classical optics. Dur-ing the past decades, research focused on a novel resonant extinction type called plasmonics that allows for en-hancement of both types of ...

EPFL2022

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials. Part II: Experimental verification of modelling approaches by infiltration of Si-Zr alloy into idealized microchannels

Ludger Weber, Caroline Hain, Giovanni Bianchi, Alberto Ortona, Manoj Kondibhau Naikade

In this work, the mechanisms leading to the pore closure in reactive melt infiltration (RMI) of carbon by pure silicon and a near eutectic Si-8 at-pct Zr alloy at 1500 and 1700 degrees C under vacuum were studied. Various geometrical configurations of micr ...

ELSEVIER SCI LTD2022

Laser Processing Methods for Perovskite Solar Cells and Modules

Mohammad Khaja Nazeeruddin

The perovskite photovoltaic technology is now transitioning from basic research to the pre-industrialization phase. In order to achieve reliable and high-performance commercial perovskite solar modules, high throughput manufacturing technologies must now b ...

WILEY-V C H VERLAG GMBH2021

The fragmentation mechanism of gold nanoparticles in water under femtosecond laser irradiation

Marcel Drabbels, Gabriele Bongiovanni, Ulrich Lorenz, Jonathan Mark Voss, Pavel Olshin, Chengcheng Yan

Plasmonic nanoparticles in aqueous solution have long been known to fragment under irradiation with intense ultrafast laser pulses, creating progeny particles with diameters of a few nanometers. However, the mechanism of this process is still intensely deb ...

2021

Time-Resolved Transmission Electron Microscopy: Instrumentation and Applications

Pavel Olshin

In recent decades, in situ electron microscopy has attracted considerable attention. The method enables real time observations of the transformations of nanoparticles under various stimuli with atomic spatial resolution. Time-resolved electron microscopy a ...

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

Laser coating of a Zr-based metallic glass on an aluminum substrate

Roland Logé, Stefano Mischler, Jamasp Jhabvala, Alejandro Roda Buch, Navid Sohrabi

Cladding of a Zr-based metallic glass (MG) on an aluminum substrate was conducted using a layer-wise laser additive manufacturing (AM) method, leading to relative densities higher than 99%. The thickness of the cladding was about 300 μm. The effect of lase ...

2020