Publications related to Femtosecond

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

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

Ultrafast Electron Microscopy of Nanoscale Charge Dynamics in Semiconductors

Fabrizio Carbone, Ivan Madan, Giovanni Maria Vanacore, Ido Kaminer, Simone Gargiulo, Francesco Barantani, Kangpeng Wang

The ultrafast dynamics of charge carriers in solids plays a pivotal role in emerging optoelectronics, photonics, energy harvesting, and quantum technology applications. However, the investigation and direct visualization of such nonequilibrium phenomena re ...

AMER CHEMICAL SOC2023

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

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

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

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

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

On the behavior of uniaxial static stress loaded micro-scale fused silica beams at room temperature

Yves Bellouard, Christos Edouardos Athanasiou, Saood Ibni Nazir

The question of whether static stress in fused silica relaxes at room temperature is still under debate. Here, we report experimental data investigating the behavior of fused silica at room temperature when subjected to static tensile stress up to 2 GPa st ...

2022

Ultrafast dynamic switching of optical response based on nonlinear hyperbolic metamaterial platform

Jiaye Wu, Qian Li

The pursuit of high-speed and on-chip optical communication systems has promoted extensive exploration of all-optical control of light-matter interactions via nonlinear optical processes. Here, we have numerically investigated the ultrafast dynamic switchi ...

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

Contactless Optical Packaging Concept for Laser to Fiber Coupling

Yves Bellouard, Saood Ibni Nazir

A novel method for the laser to fiber coupling is presented in which coarse alignment is achieved through micromachined v-grooves and mirrors in a fused silica substrate. Furthermore, fine repositioning is done in a noncontact manner by using a femtosecond ...

2021

A tunable femtosecond fiber laser source for multiphoton emission microscopy

Pierre-Marc Jean Marie Dansette

Second harmonic generation microscopy is used to image interfaces or non-centrosymmetric structures and molecules. Two-photon fluorescence microscopy can image molecules within cells without using markers. Thus those technics have lead to advances in our u ...

EPFL2021

Broadband quasi-phase-matching in dispersion-engineered all-optically poled silicon nitride waveguides

Tobias Kippenberg, Camille Sophie Brès, Rui Ning Wang, Ozan Yakar, Boris Zabelich, Junqiu Liu, Edgars Nitiss

Quasi-phase-matching (QPM) has become one of the most common approaches for increasing the efficiency of nonlinear three-wave mixing processes in integrated photonic circuits. Here, we provide a study of dispersion engineering of QPM second-harmonic (SH) g ...

2020

Fundamentals and perspectives of ultrafast photoferroic recording

Anna Pogrebna

The ability to switch ferroics (ferro-, ferri-, antiferromagnets, ferroelectrics, multiferroics) between two stable bit states is one of the keystones of modern data storage technology. Due to many new ideas, originating from fundamental research during th ...

2020

Peculiarities of second harmonic generation with chirped femtosecond pulses at high conversion efficiency

Pierre-Marc Jean Marie Dansette

Frequency doubling of an infrared laser radiation in non-linear optical crystals is a widely used technique to obtain light in the visible range. The second harmonic generation process is influenced by several well-known parameters. In this article we stud ...

ELSEVIER2020

A Monolithic Gimbal Micro-Mirror Fabricated and Remotely Tuned with a Femtosecond Laser

Yves Bellouard, Saood Ibni Nazir

With the advent of ultrafast lasers, new manufacturing techniques have come into existence. In micromachining, the use of femtosecond lasers not only offers the possibility for three-dimensional monolithic fabrication inside a single optically transparent ...

2019

Excited-state band mapping and momentum-resolved ultrafast population dynamics in In/Si(111) nanowires investigated with XUV-based time- and angle-resolved photoemission spectroscopy

Michele Puppin, Matthias Wolf

We investigate the excited state electronic structure of the model phase transition system In/Si(111) using femtosecond time-and angle-resolved photoemission spectroscopy (trARPES). An extreme ultraviolet 500 kHz laser source at 21.7 eV is utilized both to ...

AMER PHYSICAL SOC2019

Local tuning of fused silica thermal expansion coefficient using femtosecond laser

Yves Bellouard, Pieter Vlugter, Erica Kathleen Block

Femtosecond laser exposure of fused silica in the nonablative regime can lead to various localized bulk modifications of the material structure. In this paper, we show that these laser-induced modifications can be used to tune silica thermal expansion prop ...

2019

Compact laser-assisted tools for high-resolution additive manufacturing

Paul Delrot

Micro-additive manufacturing has become an enabling technology in biomedical research as it allows for instance creating functional microstructures or studying cellular interactions at the microscale. Among the various manufacturing techniques laser-actuat ...

EPFL2018