Publications associées à Towards enabling femtosecond helicity-dependent spectroscopy with high-harmonic sources

Alignment of ND3 molecules in dc-electric fields

Andreas Osterwalder, Junwen Zou, Viet Le Duc

The control of movement and orientation of gas-phase molecules has become the focus of many research areas in molecular physics. Here, ND3 molecules are polarized in a segmented, curved electrostatic guide and adiabatically aligned inside a rotatable mass ...

Aip Publishing2024

Dual-shot approach for polarization retrieval through a scattering medium

Abhijit Roy

A dual-shot technique based on the field basis addition of two statistically independent speckle patterns is developed to recover an input polarization through a scattering layer. It is proposed theoretically, and demonstrated both numerically and experime ...

Iop Publishing Ltd2024

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

Measuring electrical properties in semiconductor devices by pixelated STEM and off-axis electron holography (or convergent beams vs. plane waves)

Victor Carle Adrien Boureau

We demonstrate the use of both pixelated differential phase contrast (DPC) scanning transmission electron microscopy (STEM) and off-axis electron holography (EH) for the measurement of electric fields and assess the advantages and limitations of each techn ...

Pergamon-Elsevier Science Ltd2024

Parametric Wavelength Conversion in Waveguiding Structures: Efficiency, Bandwidth and Polarization

Arman Ayan

Photonics integrated circuits are a promising solution for the growing demands of data transmission and future system-on-chip technologies. Within this context, nonlinear optical interactions offer unique opportunities for all-optical processing, sampling, ...

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

Optothermal shaping of lamb waves with square and spiral phase fronts

Romain Christophe Rémy Fleury, Aleksi Antoine Bossart, Janez Rus

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

2024

Wandering principal optical axes in van der Waals triclinic materials

Arslan Mazitov

Nature is abundant in material platforms with anisotropic permittivities arising from symmetry reduction that feature a variety of extraordinary optical effects. Principal optical axes are essential characteristics for these effects that define light-matte ...

Nature Portfolio2024

Lithium tantalate photonic integrated circuits for volume manufacturing

Tobias Kippenberg, Kai Huang, Chen Yang, Mikhail Churaev, Xinru Ji, Yang Chen, Zihan Li, Alisa Davydova, Xi Wang, Junyin Zhang

Electro-optical photonic integrated circuits (PICs) based on lithium niobate (LiNbO3) have demonstrated the vast capabilities of materials with a high Pockels coefficient1,2. They enable linear and high-speed modulators operating at complementary metal–oxi ...

2024

Photoinduced Second-Order Nonlinearities in Centrosymmetric Media

Ozan Yakar

The interaction of light and matter enables nonlinear frequency conversion and the creation of coherent currents. The optical control of electric currents is of fundamental relevance and prominent research focus in the last decades. These photocurrents ena ...

EPFL2024

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

Majed Chergui

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

Exploring Novel Modalities for Optical Diffraction Tomography

Amirhossein Saba Shirvan

In the past decade, optical diffraction tomography has gained a lot of attention for its ability to create label-free three-dimensional (3D) images of the refractive index distribution of biological samples using scattered fields measured through holograph ...

EPFL2023

Domain Imaging and Switching Dynamics in BaTiO3-Based Photonic Integrated Devices

Jacqueline Geler Kremer

Keeping up with our constantly connected lifestyle of instant messages and video streaming has its repercussions. Data centers have been gobbling up resources becoming a significant share of the energy used worldwide. To keep up with demand and curb the en ...

EPFL2023

Dielectric Tetramer Nanoresonators Supporting Strong Superchiral Fields for Vibrational Circular Dichroism Spectroscopy

Hatice Altug, Yasaman Jahani, Bang Hyun Lee, Ming-Lun Tseng, Rui Lu, Longfang Ye, Felix Ulrich Richter

Chirality (C) is a fundamental property of objects, in terms of symmetry. It is extremely important to sense and distinguish chiral molecules in the fields of biochemistry, science, and medicine. Vibrational circular dichroism (VCD) spectroscopy, obtained ...

Amer Chemical Soc2023

Polarization-Controlled Chromo-Encryption

Olivier Martin, Hsiang-Chu Wang

The response of simple plasmonic nanorods to polarized illumination is studied in detail. Depending on the orientation of that polarization with respect to the symmetry axes of the nanostructure, a chiral response can occur, which can be analyzed through a ...

WILEY-V C H VERLAG GMBH2023

Circularly polarized planar antenna with axially symmetric beamwidth reconfigurability

Anja Skrivervik, Ismael Vico Triviño, Hannes Bartle

This contribution presents the design of a compact circularly polarized antenna featuring beamwidth reconfiguration in both the horizontal and vertical planes. The observed radiation patterns in each of the reconfigurable states present axial symmetry and ...

IEEE2023

Analysis of Non-Canonical Body-Conformal Arrays with Polarization Decomposition

Anja Skrivervik, Denys Nikolayev

Conformal phased arrays can be found in many applications due to their ability to fit tridimensional surfaces and, thanks to their scanning performance, can excel planar arrays. However, most of the previously proposed analysis methods can be applied only ...

IEEE2023

Layered metals as polarized transparent conductors

Philip Johannes Walter Moll, Matthias Carsten Putzke, Chunyu Guo, Maja Deborah Bachmann

The quest to improve transparent conductors balances two key goals: increasing electrical conductivity and increasing optical transparency. To improve both simultaneously is hindered by the physical limitation that good metals with high electrical conducti ...

Nature Portfolio2023

Spun fibres: a quasi circularly birefringent medium

Luc Thévenaz, Ana Gabriela Correa Mena, Xu Cheng

A simplified model describing the polarisation characteristics of spun fibres is proposed, aiming at determining how close to a circularly birefringent medium such a fibre is. This is of crucial importance regarding the interest of such a medium for magnet ...

SPIE2023

Element- and enantiomer-selective visualization of molecular motion in real-time

Majed Chergui, Malte Oppermann, Jérémy Raymond Jean Maurice Rouxel

Ultrafast optical-domain spectroscopies allow to monitor in real time the motion of nuclei in molecules. Achieving element-selectivity had to await the advent of time resolved X-ray spectroscopy, which is now commonly carried at X-ray free electron lasers. ...

Nature Portfolio2023