Publications associées à Canon à électrons

Plasmonic Nanostructures for Photocatalysis: Material, Photonic and Electronic Effects

Plasmonic photochemistry has a large potential to replace energy-intensive chemical processes with low-temperature, low-pressure light-driven chemical reactions. Plasmonic nanostructures have emerged as promising photocatalysts with exceptional and tunable ...

EPFL2024

First self-consistent simulations of trapped electron clouds in a gyrotron gun and comparison with experiments

Stefano Alberti, Jean-Philippe Hogge, Ioannis Pagonakis, Joaquim Loizu Cisquella, Jérémy Genoud, Francesco Romano

We report on the initial validation of the novel code FENNECS, which simulates the spontaneous formation of trapped electron clouds in coaxial geometries with strong externally applied azimuthal flows and in the presence of a residual neutral gas. For this ...

American Institute of Physics (AIP)2023

Modelling of nonneutral plasmas trapped by electric and magnetic fields relevant to gyrotron electron guns

Guillaume Michel Le Bars

Gyrotrons are a class of high-power vacuum-electronics microwave sources, which are envisioned to play an important role in the domain of magnetically confined fusion plasmas. Indeed, only gyrotrons are capable of producing continuous electromagnetic waves ...

EPFL2023

Time-Resolved Transmission Electron Microscopy: Instrumentation and Applications

Pavel Olshin

In recent decades, in situ electron microscopy has attracted considerable attention. The method enables real time observations of the transformations of nanoparticles under various stimuli with atomic spatial resolution. Time-resolved electron microscopy a ...

EPFL2021

Integration concept of an Electron Cyclotron System in DEMO

René Chavan, Minh Quang Tran, Hartmut Zohm, Konstantinos Avramidis

The pre-conceptual layout for an electron cyclotron system (ECS) in DEMO is described. The present DEMO ECS considers only equatorial ports for both plasma heating and neoclassical tearing mode (NTM) control. This differs from ITER, where four launchers in ...

2021

Characterization of a time-resolved electron microscope with a Schottky field emission gun

Marcel Drabbels, Ulrich Lorenz, Pavel Olshin

The rapid growth of the field of time-resolved and ultrafast electron microscopy has been accompanied by the active development of new instrumentation. Recently, time-resolved microscopes equipped with a field emission gun have been introduced, demonstrati ...

2020

Radiative cooling of carbon cluster anions C-2n+1(-) (n=3-5)

Eduardo Carrascosa Casado

Radiative cooling of carbon cluster anions C(2n+1)(-)C2n+1- (n = 3-5) is investigated using the cryogenic electrostatic ion storage ring DESIREE. Two different strategies are applied to infer infrared emission on slow (milliseconds to seconds) and ultraslo ...

SPRINGER2020

Advanced linear models for gyro-backward wave instabilities in gyrotrons

Jérémy Genoud

Parasitic oscillations excitation is one of the main point hindering high-power gyrotron operation for fusion application. These instabilities, besides being dangerous for the gyrotron components, could possibly degrade the electron beam quality before it ...

EPFL2019

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

Timothy Goodman, Stefano Alberti, 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

Report of recent experiments with the European 1 MW, 170 GHz CW and SP prototype gyrotrons for ITER

Stefano Alberti, Minh Quang Tran, Jean-Philippe Hogge, Christian Schlatter, Francisco Sanchez, Ioannis Pagonakis, Martin Schmid, Konstantinos Avramidis

The European 1 MW, 170 GHz industrial CW prototype gyrotron has been designed within EGYC (European GYrotron Consortium) in collaboration with the industrial partner Thales Electron Devices (TED) and under the coordination of Fusion for Energy (F4E). This ...

E D P SCIENCES2019

Femtosecond Spectroscopy of Au Hot-Electron Injection into TiO2: Evidence for Au/TiO(2 )Plasmon Photocatalysis by Bactericidal Au Ions and Related Phenomena

Juan Kiwi, Sami Rtimi

In the present work, we provide evidence for visible light irradiation of the Au/TiO2 nanoparticles' surface plasmon resonance band (SPR) leading to electron injection from the Au nanoparticles to the conduction band of TiO2. The Au/TiO2 SPR band is shown ...

2019

Metrology techniques for the verification of the alignment of the EU gyrotron prototype for ITER

Stefano Alberti, Jean-Philippe Hogge, Francisco Sanchez, Ioannis Pagonakis, Konstantinos Avramidis

The EU gyrotron for the ITER Electron Cyclotron (EC) heating system has been developed in coordinated efforts of the EGYC Consortium, Thales ED (TED) and Fusion for Energy (F4E) and under the supervision of ITER Organization Central Team. After the success ...

E D P SCIENCES2019

Interdigitated back contact silicon heterojunction solar cells featuring an interband tunnel junction enabling simplified processing

Christophe Ballif, Quentin Thomas Jeangros, Antoine Descoeudres, Antonin Faes, Gabriel Christmann, Jonas Geissbühler, Matthieu Despeisse, Bertrand Yves Paul Paviet-Salomon, Stefaan De Wolf, Nicolas Badel, Sylvain Nicolay, Benjamin Strahm, Andrea Tomasi, Loris Barraud, Johannes Peter Seif

This paper reports on the development of an innovative back-contacted crystalline silicon solar cell with passivating contacts featuring an interband tunnel junction at its electron-collecting contacts. In this novel architecture, named "tunnel-IBC", both ...

2018

Parasitic Oscillations in Smooth-Wall Circular Symmetric Gyrotron Beam Ducts

Stefano Alberti, Jérémy Genoud, Minh Quang Tran, Jean-Philippe Hogge, Trach-Minh Tran, Konstantinos Avramidis

In order to study parasitic oscillation that may occur in a realistic beam duct upstream to the gyrotron cavity, the self-consistent linear and spectral code TWANGlinspec has been modified. The large inhomogeneities in the smooth-wall beam duct geometry or ...

2018

Hydrogenated TiO2 Thin Film for Accelerating Electron Transport in Highly Efficient Planar Perovskite Solar Cells

Jingshan Luo, Yang Li, Xiaoyu Zhang, Yi Ding, Di Zhang

Intensive studies on low-temperature deposited electron transport materials have been performed to improve the efficiency of n-i-p type planar perovskite solar cells to extend their application on plastic and multijunction device architectures. Here, a TiO ...

2017

Femtosecond electron and X-ray source developments for time-resolved applications

Fernando Ardana Lamas

This manuscript summarizes the different technological developments and scientific activities in the field of ultrafast laser and electron physics which I have carried out as part of my PhD thesis. The topics addressed in my thesis range from the developme ...

EPFL2016

Electron beam dynamics in an ultrafast transmission electron microscope with Wehnelt electrode

Thomas La Grange

High temporal resolution transmission electron microscopy techniques have shown significant progress in recent years. Using photoelectron pulses induced by ultrashort laser pulses on the cathode, these methods can probe ultrafast materials processes and ha ...

Elsevier Science Bv2016

Progress on the upgrade of the TCV EC-system with two 1MW dual-frequency gyrotrons

Stefano Alberti, Timothy Goodman, Minh Quang Tran, Jean-Philippe Hogge, Jérémy Genoud, Trach-Minh Tran, Ioannis Pagonakis, Konstantinos Avramidis

The upgrade of the electron cyclotron (EC) system of the TCV tokamak has entered in its realization phase. The MW-class dual-frequency gyrotron design (84 or 126GHz/2s), based on the 140GHz W7-X gyrotron, is finalized and a contract for the manufacturing o ...

IEEE2016

Electron Energy-Loss Spectroscopy of Coupled Plasmonic Systems: Beyond the Standard Electron Perspective

Jürgen Brugger, Olivier Martin, Jérémy Butet, Gabriel David Bernasconi, Valentin Flauraud

Electron energy-loss spectroscopy (EELS) has become an experimental method of choice for the investigation of localized surface plasmon resonances, allowing the simultaneous mapping of the associated field distributions and their resonant energies with a n ...

Spie-Int Soc Optical Engineering2016

Laser arrival measurement tools for SwissFEL

Christoph Peter Hauri

SwissFEL is aiming to produce X-ray pulses from 30 fs down to the attosecond time scale. This requires the compression of the several picosecond long electron bunches produced by a photo-injector to sub-fs level. To achieve this, 40fs accurate injection of ...

Spie-Int Soc Optical Engineering2015