Publications associées à Femtosecond pulse shaping

Femtosecond-laser direct-write photoconductive patterns on tellurite glass

Yves Bellouard, Gözden Torun, Anastasia Romashkina

We report the formation of arbitrary photoconductive patterns made of tellurium (Te) nanocrystals by exposing a tellurite (TeO2-based) glass to femtosecond laser pulses. During this process, Te/TeO2-glass nanocomposite interfaces with photoconductive prope ...

American Physical Society (APS)2024

Numerical Study of the Attosecond Free-Electron Laser Pulse Generation in the Soft X-ray Regime at the SwissFEL

Longdi Zhu

Isolated attosecond pulses from an X-ray free-electron laser are in high demand for attosecond science, which enables the probing of electron dynamics by X-ray nonlinear spectroscopy and single-particle imaging. The aim of this thesis is to simulate attos ...

EPFL2024

Influence of ionization and cumulative effects on laser-induced crystallization in multilayer dielectrics

Yves Bellouard, Victor Carle Adrien Boureau, Ruben Ricca

Crystallization of amorphous layers has been demonstrated under various radically different laser-exposure conditions, including continuous wave (cw) and pulsed lasers. Here, we investigate the specific role of ionization in the crystallization of dielectr ...

2024

Laser-based manufacturing of freeform glass micro-optics through topological transformation

Samuel Youcef Benketaf

Glass has been the material of choice for making optical elements, in large part due to its intrinsic properties: a temperature-dependent viscosity, which enables shaping the material into a broad variety of functional and artistic glassware. Silica glass ...

EPFL2024

Formation Mechanism of Elemental Te Produced in Tellurite Glass Systems by Femtosecond Laser Irradiation

Yves Bellouard, Gözden Torun

The formation of elemental trigonal tellurium (t-Te) on tellurite glass surfaces exposed to femtosecond laser pulses is discussed. Specifically, the underlying elemental crystallization phenomenon is investigated by altering laser parameters in common tell ...

Wiley2023

Terahertz waveform synthesis in integrated thin-film lithium niobate platform

Ileana-Cristina Benea-Chelmus, Jérôme Faist, Francesca Fabiana Settembrini

Bridging the "terahertz gap" relies upon synthesizing arbitrary waveforms in the terahertz domain enabling applications that require both narrow band sources for sensing and few-cycle drives for classical and quantum objects. However, realization of custom ...

Nature Portfolio2023

Tunable pump compression and fast modulation for pulsed THz generation

Ileana-Cristina Benea-Chelmus, Alessandro Tomasino, Yazan Lampert Almahmoud, Shima Rajabali

We demonstrate tunable dispersion compensation of femtosecond pulses at telecom wavelengths for broadband Terahertz generation in 7.5-meter fiber link using a Silicon prism pair. The prism pair enhances the amplitude of the THz E-field in InGaAs photocondu ...

IEEE2023

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

Charge Dynamics Electron Microscopy Nanoscale Imaging of Femtosecond Plasma Dynamics

Fabrizio Carbone, Ivan Madan, Thomas La Grange, Giovanni Maria Vanacore, Gabriele Berruto, Ido Kaminer, Simone Gargiulo, Luca Piazza, Francesco Barantani, Tom Theodorus Antonius Lummen

Understanding and actively controlling the spatiotemporal dynamics of nonequilibrium electron clouds is fundamental for the design of light and electron sources, high power electronic devices, and plasma-based applications. However, electron clouds evolve ...

AMER CHEMICAL SOC2023

All-glass miniature GHz repetition rate femtosecond laser cavity

Yves Bellouard, Antoine Maxime Delgoffe, Saood Ibni Nazir, Sargis Hakobyan

Free-space optics allows for design freedom and control, but miniaturization and manufacturability are limited. Here, we present a method for manufacturing complex miniaturized free-space optical systems that combines contactless femtosecond laser-activate ...

2023

High throughput wide field second harmonic imaging of giant unilamellar vesicles

Sylvie Roke, Maksim Eremchev, David Roesel, Pierre-Marc Jean Marie Dansette

Cell-sized giant unilamellar vesicles (GUVs) are an ideal tool for understanding lipid membrane structure and properties. Label-free spatiotemporal images of their membrane potential and structure would greatly aid the quantitative understanding of membran ...

AIP Publishing2023

Comparison of Different Formulations to Compute the Ground Return Parameters in the Analysis of High-Frequency Pulse Propagation Along a Wire Above a Lossy Ground

Farhad Rachidi-Haeri, Rafael Silva Alipio

The propagation characteristics along a single-conductor line above a lossy ground are assessed considering different formulations to compute the ground correction terms in the per-unit-length line parameters. It is shown that the often-used Sunde’s formul ...

2023

PHz Electronic Device Design and Simulation for Waveguide-Integrated Carrier-Envelope Phase Detection

Yujia Yang

Carrier-envelope phase (CEP) detection of ultrashort optical pulses and low-energy waveform field sampling have recently been demonstrated using direct time-domain methods that exploit optical-field photoemission from plasmonic nanoantennas. These devices ...

IEEE Institute of Electrical and Electronics Engineers2022

Bayesian tomography of high-dimensional on-chip biphoton frequency combs with randomized measurements

Tobias Kippenberg, Junqiu Liu

Owing in large part to the advent of integrated biphoton frequency combs, recent years have witnessed increased attention to quantum information processing in the frequency domain for its inherent high dimensionality and entanglement compatible with fiber- ...

Nature Portfolio2022

Wavelength-stabilized tunable mode-locked thulium-doped fiber laser beyond 2 mu m

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We report the development of a widely tunable mode-locked thulium-doped fiber laser based on a robust chirped fiber Bragg grating (CFBG). By applying mechanical tension and compression to the CFBG, an overall tunability of 20.1 nm, spanning from 2022.1 nm ...

Optica Publishing Group2022

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

Optically Triggered Neel Vector Manipulation of a Metallic Antiferromagnet Mn2Au under Strain

Alexey Sapozhnik

The absence of stray fields, their insensitivity to external magnetic fields, and ultrafast dynamics make antiferromagnets promising candidates for active elements in spintronic devices. Here, we demonstrate manipulation of the Neel vector in the metallic ...

AMER CHEMICAL SOC2022

Ultrafast Laser Direct-Writing of Self-Organized Microstructures in Ge-Sb-S Chalcogenide Glass

Yves Bellouard, Gözden Torun

The structuring of mid-IR materials, such as chalcogenide glass (ChG), at the micro and nano scales, is of high interest for the fabrication of photonic devices in general, and for spectroscopy applications in particular. One efficient method for producing ...

2022

Ultrashort Pulse Excited Tip-Enhanced Raman Spectroscopy in Molecules

Klaus Kern, Yang Luo

Vibrational fingerprints of molecules and lowdimension materials can be traced with subnanometer resolution by performing Tip-enhanced Raman spectroscopy (TERS) in a localization of light in the plasmonic nanocavity of the STM enables high spatial resoluti ...

AMER CHEMICAL SOC2022