Publications associées à Laser au dioxyde de carbone

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

Persistent enhancement of exciton diffusivity in CsPbBr3 nanocrystal solids

Seryio Saris

In semiconductors, exciton or charge carrier diffusivity is typically described as an inherent material property. Here, we show that the transport of excitons among CsPbBr3 perovskite nanocrystals (NCs) depends markedly on how recently those NCs were occup ...

Amer Assoc Advancement Science2024

Dissipative Kerr soliton generation at 2μm in a silicon nitride microresonator

Camille Sophie Brès, Anton Stroganov, Ozan Yakar, Christian André Clément Lafforgue, Marco Clementi, Anamika Nair Karunakaran

Chip -scale optical frequency combs enable the generation of highly -coherent pulsed light at gigahertz-level repetition rates, with potential technological impact ranging from telecommunications to sensing and spectroscopy. In combination with techniques ...

Optica Publishing Group2024

Wavelength-stabilized figure-of-9 thulium-doped all-fiber laser emitting 560 fs pulses

Camille Sophie Brès, Moritz Bartnick, Gayathri Bharathan

We demonstrate a figure-of-9 all-fiber thulium-doped laser (TDFL) that generates 560 fs long pulses at 1948 nm wavelength. In order to achieve self-starting passive mode-locking, we utilize an in-fiber Faraday rotator to induce a nonreciprocal phase shift. ...

Iop Publishing Ltd2024

Fully reconfigurable MEMS-based second-order coupled-resonator optical waveguide (CROW) with ultra-low tuning energy

Niels Quack, Alain Yuji Takabayashi

Integrated microring resonators are well suited for wavelength-filtering applications in optical signal processing, and cascaded microring resonators allow flexible filter design in coupledresonator optical waveguide (CROW) configurations. However, the imp ...

Optica Publishing Group2023

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

Ultrafast tunable lasers using lithium niobate integrated photonics

Tobias Kippenberg, Rui Ning Wang, Anat Siddharth, Mikhail Churaev, Viacheslav Snigirev, Junqiu Liu, Guanhao Huang

Early works(1) and recent advances in thin-film lithium niobate (LiNbO3) on insulator have enabled low-loss photonic integrated circuits(2,3), modulators with improved half-wave voltage(4,5), electro-optic frequency combs(6) and on-chip electro-optic devic ...

NATURE PORTFOLIO2023

A chip-scale second-harmonic source via self-injection-locked all-optical poling

Tobias Kippenberg, Camille Sophie Brès, Junqiu Liu, Edgars Nitiss, Marco Clementi

Second-harmonic generation allows for coherently bridging distant regions of the optical spectrum, with applications ranging from laser technology to self-referencing of frequency combs. However, accessing the nonlinear response of a medium typically requi ...

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

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

Balancing high-speed rotors at low speed using optimized parametric excitation and tuned nonlinear feedback

Amit Yedidia Dolev

The paper presents an improved slow-speed mass balancing procedure capable of reducing high-speed related imbalance. Parametric excitation is used to project the small imbalance forces onto a chosen mode of vibration, corresponding to a high critical rotat ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Gain-switched semiconductor laser driven soliton microcombs

Tobias Kippenberg, Junqiu Liu, Erwan Guillaume Albert Lucas, Wenle Weng, Jijun He

Using phase-engineered coherent laser pulses produced by gain-switched semiconductor lasers, we generate low-power-threshold soliton microcombs whose repetition frequencies are in the X-band and K-band microwave ranges. (c) 2021TheAuthor(s) ...

IEEE2021

Self-Injection Locking of a Gain-Switched Laser Diode

Andrey Voloshin

We experimentally observe a self-injection locking regime of the gain-switched laser to a high-Q optical microresonator. We reveal that the comb generated by the gain-switched laser experiences a dramatic reduction of comb-teeth linewidths in this regime. ...

American Physical Society (APS)2021

Helimagnons and Skyrmion Dynamics in Cu2OSeO3 and Fe/Gd Multilayers Explored by Brillouin Light Scattering and X-ray Microscopy

Ping Che

Spin dynamics in skyrmion hosting materials provide novel functionality in magnonics because of the formation of a novel magnon band structure and the nanoscale sizes of magnetic skyrmions. In this thesis, we explore the spin dynamics in the chiral magnet ...

EPFL2021

Probing unconventional performance of fiber resonators: light storage, generation and manipulation

Ivan Cardea

This thesis aims at investigating the performance of figure-9 (figure-of-nine) optical fiber resonators as a practical solution for light storage, light generation and manipulation. The first part of the thesis focuses on a theoretical and experimental stu ...

EPFL2021

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

Cavity-assisted preparation and detection of a unitary Fermi gas

Jean-Philippe Brantut, Victor Youri Helson, Kevin Etienne Robert Roux, Hideki Konishi

We report on the fast production and weakly destructive detection of a Fermi gas with tunable interactions in a high finesse cavity. The cavity is used both with far off-resonant light to create a deep optical dipole trap, and with near-resonant light to r ...

2021

Measurement of Frequency Tuning Curves of Soliton Self-Injection Locking to a Nonlinear Microresonator

Tobias Kippenberg, Junqiu Liu, Grigorii Likhachev, Andrey Voloshin

Self-injection locking effect eliminates the need for bulky narrow-linewidth, tunable, continuous-wave laser for pumping of high-Q optical microresonators, utilizing bare laser diodes. Here we propose an experimental technique, which allows measuring the m ...

IEEE2020

Ultrafast carbothermal reduction of silica to silicon using a CO2 laser beam

Jaeki Jeong

We report the extraction of silicon via a carbothermal reduction process using a CO2 laser beam as a heat source. The surface of a mixture of silica and carbon black powder became brown after laser beam irradiation for a few tens of seconds, and clear peak ...

NATURE RESEARCH2020

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