Publications associées à Femtochimie

Experimental demonstration of attosecond pump-probe spectroscopy with an X-ray free-electron laser

Christoph Bostedt, Zhaoheng Guo, Xiang Li, Jun Wang, Siqi Li, Zhen Zhang

Pump-probe experiments with subfemtosecond resolution are the key to understanding electronic dynamics in quantum systems. Here we demonstrate the generation and control of subfemtosecond pulse pairs from a two-colour X-ray free-electron laser. By measurin ...

Nature Publishing Group2024

Investigating Non-equilibrium Physics in Wide Bandgap Semiconductors and Quantum Materials via Ultrafast Spectroscopy

Hui-Yuan Chen

This thesis uses femtosecond laser spectroscopy in studying strong correlation in condensed matters that are pertinent to future technology: a wide bandgap perovskite and a quantum material, with the employment of ultrafast time-resolved spectroscopy in th ...

EPFL2024

Exciton migration in two-dimensional materials

Excitons play an essential role in the optical response of two-dimensional materials. These are bound states showing up in the band gaps of many-body systems and are conceived as quasiparticles formed by an electron and a hole. By performing real-time simu ...

Nature Portfolio2024

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

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

Analytics at the nanometer and nanosecond scales by short electron pulses in an electron microscope

Thomas La Grange

Chemical reactions and phase transformations in nanometer-size objects may happen at very short timescales, so conventional characterization tools are not applicable. A new technique combining high spatial and temporal resolution is ultrafast (or dynamic) ...

SPRINGER2022

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

Gain-switched semiconductor laser driven soliton microcombs

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

Dissipative Kerr soliton generation using self-injection-locked III-V lasers has enabled fully integrated hybrid microcombs that operate in turnkey mode and can access microwave repetition rates. Yet, continuous-wave-driven soliton microcombs exhibit low e ...

Nature Research2021

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