Publications by Jérémy Genoud

Cavity Design for a High-Power, Frequency-Agile 198 GHz Gyrotron

Gyrotrons are high-power microwave sources, readily applied in diverse fields ranging from fusion research and thermal treatment of materials to advanced spectroscopic techniques. Here, we provide the cavity design of a 198 GHz gyrotron to generate microwa ...

2025

Effects of reflected electrons on the efficiency of high-power gyrotrons

Jean-Philippe Hogge, Jérémy Genoud

Efficiency is a key factor for high-power gyrotrons, particularly in future fusion power plants, where a large number of gyrotron units will be required for plasma heating. A single-stage depressed collector enhances efficiency from approximately 35% to 50 ...

2025

Effect of Ion Irradiation on the Surface Electrical Conductivity of Cucrzr at High Frequencies

René Chavan, Timothy Goodman, Jean-Philippe Hogge, Jérémy Genoud, Avelino Mas Sanchez, Anastasia Xydou

The ohmic losses in the Electron Cyclotron Heating system of the DEMO nuclear fusion reactor depend on the surface electrical conductivity of the material at the frequency of the mm-wave beams generated in the gyrotrons. To reduce the ohmic losses, many co ...

ELSEVIER SCIENCE SA2025

Electron trapping in gyrotron electron guns: Validation of the FENNECS code with the T-REX experiment

Stefano Alberti, Timothy Goodman, Jean-Philippe Hogge, Mario Ludovico Podesta, Joaquim Loizu Cisquella, Jérémy Genoud, Guillaume Michel Le Bars, Falk Hans Braunmüller, Francesco Romano

Gyrotrons are essential devices for the development of nuclear fusion, but their design and reliable operation still present numerous challenges. In particular, certain gyrotrons encounter issues related to trapped electron clouds in the magnetron injectio ...

AIP Publishing2025

Design and First Tests of the Trapped Electrons Experiment T-REX

Stefano Alberti, Damien Fasel, Joaquim Loizu Cisquella, Severino Antonioni, Jérémy Genoud, Steve Couturier, Francesco Romano

Gyrotrons are essential for electron cyclotron resonance heating (ECRH) in fusion reactors, making efficient operation crucial for advancing fusion energy. Past experiments revealed instability issues due to trapped electrons in the magnetron injection gun ...

AIP Publishing2024

Thorough Simulation of High-Power Gyrotron Cavity Interaction in the Hard Excitation Regime

Jean-Philippe Hogge, Jérémy Genoud

Using the new interaction code Phaedra, a thorough and systematic investigation of the operation of a high-power gyrotron cavity in the hard excitation regime took place. The preliminary result of this analysis shows that in the hard excitation regime, the ...

Institute of Electrical and Electronics Engineers Inc.2024

Study of Ionized Particles in a Gyrotron Using a Full Gyrotron Simulation Model

Jean-Philippe Hogge, Jérémy Genoud

The ionization of the residual gas in gyrotrons causes the generation of positively charged ions and negatively charged electrons. Using the electron optics code Ariadne, it was possible to simulate the behavior of these electrons in the overall gyrotron g ...

Institute of Electrical and Electronics Engineers Inc.2024

Electron optics simulation in the overall gyrotron geometry

Jean-Philippe Hogge, Jérémy Genoud

A model is presented for simulating the electron beam within the entire gyrotron geometry using an electron optics code. The model incorporates the influence of the electromagnetic fields generated by the cavity's operational mode through a simple self-con ...

American Institute of Physics (AIP)2024

Experimental research on the TCV tokamak

Patrick Blanchard, Stefano Alberti, Ambrogio Fasoli, Timothy Goodman, Yves Martin, Olivier Sauter, Henri Weisen, Ivo Furno, Holger Reimerdes, Jean-Philippe Hogge, Stefano Coda, Alexander Karpushov, Yanis Andrebe, Duccio Testa, Benoît Labit, Christian Gabriel Theiler, Federico Alberto Alfredo Felici, Jérémy Genoud, Hugo De Oliveira, Antoine Pierre Emmanuel Alexis Merle, Antoine Baillod, Joan Decker, Cedric Kar-Wai Tsui, Pedro Andres Molina Cabrera, Umar Sheikh, Cristian Galperti, Marcelo Baquero Ruiz, Aylwin Iantchenko, Mengdi Kong, Francesco Carpanese, Federico Pesamosca, Olivier Claude Martin Février, Simon Van Mulders, Nicola Offeddu, Garance Hélène Salomé Durr-Legoupil-Nicoud, Maurizio Giacomin, Filippo Bagnato, Davide Galassi, Arsène Stéphane Tema Biwole, Lorenzo Martinelli, , , , , , , , , , , , , , , , , , , , , , , ,

A model of electron beam neutralization for gyrotron simulations

Jean-Philippe Hogge, Jérémy Genoud

A numerical model is presented to describe the electron beam neutralization during long-pulse and continuous-wave operation in gyrotrons. This model has been implemented in the electrostatic, self-consistent electron optics code Ariadne. Using this model, ...

Melville2024

FENNECS: a novel particle-in-cell code for simulating the formation of magnetized non-neutral plasmas trapped by electrodes of complex geometries

Stefano Alberti, Jean-Philippe Hogge, Joaquim Loizu Cisquella, Jérémy Genoud, Guillaume Michel Le Bars, Francesco Romano

This paper presents the new 2D electrostatic particle -in -cell code FENNECS developed to study the formation of magnetized non -neutral plasmas in geometries with azimuthal symmetry. This code has been developed in the domain of gyrotron electron gun desi ...

2024

Experimental characterization of the TCV dual-frequency gyrotron and validation of numerical codes including the effect of After Cavity Interaction

Stefano Alberti, Damien Fasel, Timothy Goodman, Jean-Philippe Hogge, Ugo Siravo, Jérémie Dubray, Matthieu Toussaint, Jérémy Genoud, Falk Hans Braunmüller

A dual-frequency gyrotron has been developed within the context of the recent Tokamak à Configuration Variable (TCV) upgrade. The gyrotron is designed to generate a 1 MW, 2 seconds RF wave at 84 or 126 GHz. Before integrating the gyrotrons in the TCV tokam ...

2024

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

Stefano Alberti, Jean-Philippe Hogge, Joaquim Loizu Cisquella, Ioannis Pagonakis, 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

Tests and Qualification of the European 1 MW, 170 GHz CW Gyrotron in an ITER relevant configuration at SPC

Stefano Alberti, Timothy Goodman, Jean-Philippe Hogge, Francisco Sanchez, Jérémy Genoud, Konstantinos Avramidis

After an initial testing period at the Karlsruhe Institute of Technology, the upgraded EU 1 MW, 170 GHz continuous wave (CW) industrial prototype gyrotron (TH1509U) for Electron Cyclotron Resonance Heating and Current Drive (ECRH&CD) in ITER has been trans ...

IEEE2022

Development of Kilowatt THz Gyrotrons for Pulsed Dynamic Nuclear Polarization - Cavity Design Code Phaedra -

Stefano Alberti, Jean-Philippe Hogge, Jérémy Genoud

A significant effort has recently been initiated at ETHZ for the development of high frequency, high power, frequency-agile gyrotrons for DNP-NMR spectroscopy. In this context an in house cavity interaction code is under development. In this paper, some de ...

IEEE2022

Linear studies of spurious backward-wave instabilities in a dielectric-loaded smooth-wall gyrotron beam ducts

Stefano Alberti, Jean-Philippe Hogge, Jérémy Genoud

Recently developed self-consistent models for beam-wave interaction simulations of a gyrotron oscillator have been extended to study spurious backward-wave instabilities in smooth-wall circular symmetric beam ducts. Starting from a purely metallic case, th ...

IEEE2020

Megawatt power generation of the dual-frequency gyrotron for TCV at 84 and 126 GHz, in long pulses

Stefano Alberti, Damien Fasel, Timothy Goodman, Blaise Marlétaz, Minh Quang Tran, Jean-Philippe Hogge, Ugo Siravo, Christian Moura, Jérémie Dubray, Ioannis Pagonakis, Jonathan Sylvain Masur, Matthieu Toussaint, Jérémy Genoud, Konstantinos Avramidis

In the frame of the TCV Tokamak upgrade, two 84/126 GHz/2 s dual frequency gyrotrons designed by SPC and KIT and manufactured by THALES will be added to the existing EC-System. The first unit has been delivered to EPFL-SPC and tested. In the commissioning ...

2020

Recent experiments with the European 1MW, 170GHz industrial CW and short-pulse gyrotrons for ITER

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

The European Gyrotron Consortium (EGYC) is developing the European 1 MW, 170 GHz Continuous Wave (CW) industrial prototype gyrotron for ITER in cooperation with Thales Electron Devices (TED) and Fusion for Energy (F4E). This conventional, hollow-cavity gyr ...

ELSEVIER SCIENCE SA2019

Overview on recent progress in magnetron injection gun theory and design for high power gyrotrons

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

The magnetron injection gun (MIG) is one of the most critical subcomponents in gyrotrons. The electron beam, which has the primary role on the gyrotron operation, is generated and configured at this part of the tube. The electron beam properties determine ...

E D P SCIENCES2019

From W7-X Towards ITER and Beyond: 2019 Status on EU Fusion Gyrotron Developments

Stefano Alberti, Damien Fasel, Blaise Marlétaz, Jean-Philippe Hogge, Jérémie Dubray, Ioannis Pagonakis, Jérémy Genoud, Konstantinos Avramidis

In Europe, the research and development with main focus on achieving robust industrial designs of series gyrotrons for electron cyclotron heating and current drive of today's nuclear fusion experiments and towards a future DEMOnstration fusion power plant ...

IEEE2019