Publications associées à Grazing angle X-ray fluorescence from periodic structures on silicon and silica surfaces

3D diffractive optics for linear interconnects and nonlinear processing

The optical domain presents potential avenues for enhancing both computing and communication due to its inherent properties of bandwidth, parallelism, and energy efficiency. This research focuses on harnessing 3-Dimensional (3D) diffractive optics for nove ...

EPFL2024

The new X-ray/visible microscopy MAXWELL technique for fast three-dimensional nanoimaging with isotropic resolution

Giorgio Margaritondo, Lin Yang

Microscopy by Achromatic X-rays With Emission of Laminar Light (MAXWELL) is a new X-ray/visible technique with attractive characteristics including isotropic resolution in all directions, large-volume imaging and high throughput. An ultrathin, laminar X-ra ...

Nature Portfolio2022

Optical metasurfaces: synthesis, nanofabrication, and colorful applications

Hsiang-Chu Wang

In this thesis, we mainly utilize silver to construct the meta-atoms. Although suffering from easily oxidized, its excellent lossless property throughout the visible range makes it suitable for study. When preserved properly, silver-made metasurfaces can s ...

EPFL2022

Active Ferromagnetic Metasurface with Topologically Protected Spin Texture for Spectral Filters

Haiming Yu, Dirk Grundler, Jilei Chen

Electromagnetic metasurfaces modulate a material's response to electromagnetic waves by specifically arranged elements with dimensions below the wavelength. They have opened new fields of research, including flat optics and nanophotonics on a chip. Ferroma ...

2022

On the Complete Radiation Pattern of a Vertical Hertzian Dipole Above a Low-Loss Ground

Krzysztof Michalski, Juan Ramon Mosig

The complete radiation field pattern of a vertical Hertzian dipole antenna on or above a lossless or low-loss dielectric half-space is studied using a rigorous Sommerfeld formalism. The reflected fields in the air above the interface and the subsurface fie ...

Ieee-Inst Electrical Electronics Engineers Inc2021

Optical element

Niels Quack, Gergely Huszka, Marcell Kristof Kiss

The present invention concerns an optical grating comprising a body defining a first external surface and a second external surface. The first external surface defines a periodic structure comprising a plurality of elongated protrusions and a plurality of ...

2020

Ultrasensitive hyperspectral imaging and biodetection enabled by dielectric metasurfaces

Volkan Cevher, Hatice Altug, Filiz Yesilköy, Andreas Tittl, Yasaman Jahani, Eduardo Romero Arvelo, Mingkai Liu

Metasurfaces based on resonant subwavelength photonic structures enable novel ways of wavefront control and light focusing, underpinning a new generation of flat-optics devices. Recently emerged all-dielectric asymmetric metasurfaces, composed of arrays of ...

Nature Publishing Group2019

A Compact Laser-Steering End-Effector for Transoral Robotic Surgery

Laryngeal cancer treatments, while curative, often lead to voice impairment. Minimally invasive surgical methods that facilitate greater preservation of healthy tissue have recently emerged, but they are still limited in important ways. In this work, we de ...

IEEE2019

Raman imaging through multimode sapphire fiber

Demetri Psaltis, Christophe Moser, Damien Claude-Marie Loterie, Georgia Konstantinou, Sunan Deng

We report on a sapphire fiber Raman imaging probe's use for challenging applications where access is severely restricted. Small-dimension Raman probes have been developed previously for various clinical applications because they show great capability for d ...

OPTICAL SOC AMER2019

Design and implementation of quasi-optical components for the upgrade of the TCV EC-system

Stefano Alberti, Timothy Goodman, Jean-Philippe Hogge, Laurie Porte, Matthieu Toussaint, Florian Ramseyer

The EC-system of the TCV tokamak is progressively being upgraded with the addition of two MW-class dual-frequency gyrotrons (84 and 126 GHz/2s/1MW). In order to connect the two gyrotrons to the existing low field side and top launchers, new waveguide routi ...

ELSEVIER SCIENCE SA2019

Experimental station Bernina at SwissFEL: condensed matter physics on femtosecond time scales investigated by X-ray diffraction and spectroscopic methods

Paul Beaud, Christopher Alexander Arrell, Christoph Peter Hauri, Giulia Fulvia Mancini, Jochen Rittmann

The Bernina instrument at the SwissFEL Aramis hard X-ray free-electron laser is designed for studying ultrafast phenomena in condensed matter and material science. Ultrashort pulses from an optical laser system covering a large wavelength range can be used ...

International Union of Crystallography (IUCr)2019

Method, apparatus and program for processing a circular light field

Martin Vetterli, Loïc Arnaud Baboulaz, Zhou Xue

Method for processing a circular light field comprising the step of receiving or storing a circular light field matrix, wherein the circular light field matrix comprises pixel data for different circumferential angles and for different incidence angles, wh ...

2017

Tomography-based radiative characterisation of decomposing carbonaceous heat shield materials

Pénélope Leyland, Sophia Haussener, Nikhil Banerji

This work evaluates the changes in radiative properties of two decomposing carbonaceous porous materials, each composed of two semitransparent, homogeneous and isotropic phases. The understanding of the complex dependence of macroscopic optical behaviour o ...

Pergamon-Elsevier Science Ltd2017

Transition of optical regime in miniaturized optical systems: light interactions beyond the refraction limit

Hans Peter Herzig, Myun Sik Kim, Toralf Scharf

We investigate the transition of optical regimes of miniaturized optical systems using two canonical examples, where the refraction of light limits the system performance. A ball-lens and a solid immersion lens (SIL) are considered, whose refractive respon ...

Spie-Int Soc Optical Engineering2016

Design of periodic nano- and macro-scale textures for high-performance thin-film multi-junction solar cells

Christophe Ballif, Franz-Josef Haug, Etienne Antoine Julien Moulin

Surface textures in thin-film silicon multi-junction solar cells play an important role in gaining the photocurrent of the devices. In this paper, a design of the textures is carried out for the case of amorphous silicon/micro-crystalline silicon (a-Si:H/m ...

Iop Publishing Ltd2016

Generation of 0.9-mJ THz pulses in DSTMS pumped by a Cr:Mg2SiO4 laser

Christoph Peter Hauri

We report on high-field terahertz transients with 0.9-mJ pulse energy produced in a 400 mm(2) partitioned organic crystal by optical rectification of a 30-mJ laser pulse centered at 1.25 mu m wavelength. The phase-locked single-cycle terahertz pulses cover ...

Optical Society of America2014

Combining Monte Carlo methods with coherent wave optics for the simulation of phase-sensitive X-ray imaging

Peter Modregger, Marco Stampanoni

Phase-sensitive X-ray imaging shows a high sensitivity towards electron density variations, making it well suited for imaging of soft tissue matter. However, there are still open questions about the details of the image formation process. Here, a framework ...

International Union of Crystallography2014

Improving metal reflectors by suppressing surface plasmon polaritons: a priori calculation of the internal reflectance of a solar cell

Christophe Ballif, Stefaan De Wolf

Imperfect internal reflectance of near-bandgap light reduces the performance of all solar cells, and becomes increasingly detrimental as absorbers become thinner. We consider light incident on the silicon/dielectric/metal structure at the back of rear-pass ...

Nature Publishing Group2013

On Micro Optical Elements for Efficient Light Diffusion

Roland Andreas Bitterli

Efficient light management is one of the key issues in modern energy conversion systems, be it to collect optical power or to redistribute light generated by high power light emitters. This thesis touches mainly on the subject of efficient light redistribu ...

EPFL2013

Obliquely incident wave propagation across rock joints with virtual wave source method

Jian Zhao, Jianbo Zhu

Due to the presence of joints, waves are greatly attenuated when propagating across rock masses. Zhu et al. (2011) (Normally incident wave propagation across a joint set with virtual wave source method. J. Appl. Geophys.73, 283-288.) studied normally incid ...

Elsevier2013