Publications associées à Ultrafast Population Dynamics of Surface-Active Dyes during Electrochemically Controlled Ion Transfer across a Liquid|Liquid Interface

Progress and prospects in nonlinear extreme-ultraviolet and X-ray optics and spectroscopy

Free-electron lasers and high-harmonic-generation table-top systems are new sources of extreme-ultraviolet to hard X-ray photons, providing ultrashort pulses that are intense, coherent and tunable. They are enabling a broad range of nonlinear optical and s ...

NATURE PORTFOLIO2023

Size dependence of second-harmonic scattering from nanoparticles: Disentangling surface and electrostatic contributions

Arianna Marchioro, Sylvie Roke, Bingxin Chu

Polarimetric angle-resolved second-harmonic scattering (AR-SHS) is an all-optical tool enabling the study of unlabeled interfaces of nano-sized particles in an aqueous solution. As the second harmonic signal is modulated by interference between nonlinear c ...

AIP Publishing2023

Spectroscopy and dynamics at liquid water interfaces

Bruno Credidio

This thesis is a detailed description of three experimental investigations on aqueous interfaces. All projects made use of the microjet technology or the more recently developed flat-jet technique which enables the implementation of liquid water in vacuum ...

EPFL2022

Optically reconfigurable quasi-phase-matching in silicon nitride microresonators

Camille Sophie Brès, Jianqi Hu, Anton Stroganov, Edgars Nitiss

Quasi-phase-matching has long been a widely used approach in nonlinear photonics, enabling efficient parametric frequency conversions such as second-harmonic generation. However, in silicon photonics the task remains challenging, as materials best suited f ...

Nature Publishing Group2022

Hidden bulk and surface effects in the spin polarization of the nodal-line semimetal ZrSiTe

Helmuth Berger, Marco Grioni, Arnaud Magrez, Oleg Yazyev, Alberto Crepaldi, Mauro Fanciulli, Gianmarco Gatti, Daniel Gosalbez Martinez, Silvan Dino Marcos Roth

Local inversion symmetry breaking in centrosymmetric materials can lead to large spin polarization of the electronic band structure in separate sectors of the unit cell. Here, the authors reveal such hidden spin polarisation in ZrSiTe using spin and angle ...

NATURE RESEARCH2021

Mapping Electrochemical Heterogeneity at Gold Surfaces: A Second Harmonic Imaging Study

Arianna Marchioro, Sylvie Roke, Igor Nahálka

Designing efficient catalysts requires correlating surface structure and local chemical composition with reactivity on length scales from nanometers to tens of microns. While much work has been done on this structure/function correlation on single crystals ...

2020

Photoemission from non-polar aromatic molecules in the gas and liquid phase

Majed Chergui, Frank van Mourik, Christopher Alexander Arrell, Lars-Hendrik Mewes, José Javier Pancracio Ojeda Andara, Jakob Grilj, Luca Longetti

The photoelectron spectra of both liquid and gas phase aromatic molecules are reported. The spectra were obtained using a 34.1 eV source produced by high harmonic generation and analysed with the help of high-level ab initio simulations using the reflectio ...

ROYAL SOC CHEMISTRY2020

Enhanced second harmonic generation of gold nanostars: optimizing multipolar radiation to improve nonlinear properties

Jérémy Raymond Jean Maurice Rouxel

We report a detailed investigation on the second harmonic generation (SHG) emission from single 150 nm diameter non-centrosymmetric gold nanoparticles. Polarization-resolved analysis together with scanning electron microscopy images shows that these nanost ...

2019

Two dimensional diffusion-controlled triplet–triplet annihilation kinetics

Pierre-François Marie Brevet, Hubert Girault, Astrid Johana Olaya Avendano, Grégoire Clément Gschwend, Morgan Kazmierczak

Diffusion controlled chemical reactions are usually observed in three dimensionalmedia. In contrast, planar bimolecular reactions taking place between reagents adsorbed at a soft interface are two-dimensional and therefore cannot be studied within the same ...

2019

Integrated Gallium Phosphide Photonics

Katharina Schmeing

The integration of new materials mediating light-matter interaction in nanoscale devices is a persistent goal in nanophotonics. One of these materials is Gallium phosphide, which offers an attractive combination of a high refractive index (n=3.05 at a wave ...

EPFL2019

Imaging of transition charge densities involving carbon core excitations by all X-ray sum-frequency generation

Jérémy Raymond Jean Maurice Rouxel

X-ray diffraction signals from the time-evolving molecular charge density induced by selective core excitation of chemically inequivalent carbon atoms are calculated. A narrowband X-ray pulse selectively excites the carbon K-edge of the -CH3 or -CH2F group ...

ROYAL SOC2019

Light Confinement and Nonlinear Light-Matter Interaction in Semiconductor Photonic Crystal Cavities

Mohamed Sabry Abdel-Aliem Mohamed

The ability to control and manipulate light is a fundamental aspect that is at the very core of the development of integrated photonic circuits. It is desirable to achieve such control down to a scale that is comparable to or smaller than the wavelength of ...

EPFL2018

Quantum State–Resolved Studies of Chemisorption Reactions

Rainer Beck, Helen Jane Chadwick

Chemical reactions at the gas–surface interface are ubiquitous in the chemical industry as well as in nature. Investigating these processes at a microscopic, quantum state–resolved level helps develop a predictive understanding of this important class of r ...

Annual Reviews2017

Optical second harmonic generation from nanostructured graphene: a full wave approach

Olivier Martin, Gabriel David Bernasconi, Raziman Thottungal Valapu, Jérémy Butet, Bruno Majérus

Optical second harmonic generation (SHG) from nanostructured graphene has been studied in the framework of classical electromagnetism using a surface integral equation method. Single disks and dimers are considered, demonstrating that the nonlinear convers ...

2017

Quantum state resolved gas–surface reaction dynamics experiments: a tutorial review

Rainer Beck, Helen Jane Chadwick

We present a tutorial review of our quantum state resolved experiments designed to study gas–surface reaction dynamics. The combination of a molecular beam, state specific reactant preparation by infrared laser pumping, and ultrahigh vacuum surface analysi ...

Royal Society of Chemistry2016

Ultrafast Photoelectron Spectroscopy of Liquid Samples

José Javier Pancracio Ojeda Andara

This thesis focuses on the commissioning and characterization of HARMONIUM, an ultrafast tunable EUV source based on high-harmonic generation for performing photoelectron spectroscopy of liquids. In ultrafast photoelectron spectroscopy a short pump pulse i ...

EPFL2016

Second Harmonic and Sum-Frequency Generation from Aqueous Interfaces Is Modulated by Interference

Sylvie Roke, Cornelis Ulrich Lütgebaucks

The interfacial region of aqueous systems also known as the electrical double layer can be characterized on the molecular level with second harmonic and sum-frequency generation (SHG/SFG). SHG and SFG are surface specific methods for isotropic liquids. Her ...

American Chemical Society2016

Resonance in swirling wakes and sloshing waves : non-normal and sublinear effects

Francesco Viola

Similarly to mechanical structures, stable flows can exhibit resonance when perturbed by an impulsive or harmonic forcing. Swirling wakes and sloshing waves belong to this kind of flows and manifest large energy response when excited close to their natural ...

EPFL2016

Freezing effects of oil-in-water emulsions studied by sum-frequency scattering spectroscopy

Sylvie Roke, Nikolay Smolentsev

Temperature-dependent sum-frequency scattering spectroscopy is used to study the properties of hexadecane and dodecane oil droplets in water. The sum-frequency scattering spectra contain vibrational bands that correspond to the symmetric and antisymmetric ...

Amer Inst Physics2016

Ultrafast electron dynamics in epitaxial graphene investigated with time- and angle-resolved photoemission spectroscopy

Marco Grioni, Alberto Crepaldi, Jens Christian Johannsen

In order to exploit the intriguing optical properties of graphene it is essential to gain a better understanding of the light-matter interaction in the material on ultrashort timescales. Exciting the Dirac fermions with intense ultrafast laser pulses trigg ...

Iop Publishing Ltd2015