SFP Alpes

Festival Remue-Méninges à GreEN-ER
2026-06-02 08:30 - 2026-06-04 16:00 (Europe/Paris) | GreEN-ER – Hall, 21 avenue des Martyrs, Grenoble, 38000, France
Une nouvelle édition du festival scientifique « Remue-Méninges » à destination des enfants (mais qui peut aussi intéresser les adultes !) se tiendra dans le hall du bâtiment GreEN-ER du mardi 2 au jeudi 4 juin. Les ateliers seront ouverts aux scolaires et au public de 8h30 à 11h et de 13h à 16h.

Damien GREGOIRE (IGMM, Montpellier, France)
2026-06-02 11:00 - 12:00 | IAB – Salle de séminaire, IAB Site Santé - Allée des Alpes, La Tronche, 38700, France
In vivo modeling of tumor heterogeneity in hepatocellular carcinoma
Résumé :
Our research aims at a better understanding of how various combinations of oncogenic events drive tumorigenesis. We address two major questions in cancer biology, within the context of inter-tumoral heterogeneity: (1) what mechanisms underlie oncogenic cooperation in shaping of the tumor cell fate, and (2), how does the genetic identity of a tumor influence its interactions with the microenvironment ?
We explore these questions in the context of hepatocellular carcinoma (HCC), the most common primary liver cancer. Our approach combines functional studies with advanced preclinical mouse models, particularly in vivo hepatocyte transfection via hydrodynamic gene transfer. We focus our investigations on tumors driven by either FGF19 overexpression or a spectrum of p53 mutations.
In this talk at IAB, I will present recent findings on these two distinct families of hepatic tumors. Our ultimate goal is to elucidate how the genetic profile of HCC shapes the tumor cell phenotype, its interactions with the tumor microenvironment—especially immune cells—and its response to treatments.
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Contact : thomas.decaens@univ-grenoble-alpes.fr

Marielena VELASCO-ENRIQUEZ (LMGP, Institut Néel)
2026-06-02 14:00 - 15:00 | LMGP – salle des séminaires, Grenoble INP -Phelma 3 parvis Louis Néel, Grenoble, 38054, France
Chemical pathways to obtain Ga2O3 films for next generation power electronics and optoelectronics
Résumé :
Ultrawide bandgap semiconductors like β-Ga2O3 are promising candidates for power electronics and optoelectronics thanks to their large bandgap energy (4.6 – 4.9 eV), high breakdown electric field (~8 MV/cm), broadband photodetection, and availability of high-quality substrates.[1] Beyond the thermodynamically stable β-Ga2O3, metastable polymorphs (α, γ, δ, κ) may offer additional functionalities, including piezoelectricity (κ-phase).[2]
This work explores two different chemical approaches in vapor phase and aqueous solution to grow Ga₂O₃ thin films and microstructures on c-plane sapphire substrates. First, pulsed-liquid injection MOCVD (PLI-MOCVD), that unlike conventional MOCVD systems, enables fine control over precursor delivery and dosing, improving chemical yield and reducing gallium waste, an important sustainability consideration.[3] Second, chemical bath deposition (CBD) followed by thermal annealing that offers a low-cost, tunable pathway to obtain crystalline Ga₂O₃,[4] though the link between growth parameters and final properties remains poorly understood.
By adapting and systematically investigating both methods, the impact of key parameters on morphology, structure, chemistry, and optical properties using a broad range of characterization techniques (SEM, XRD, TEM, XPS, Raman, UV-Vis, cathodoluminescence, etc.) is studied. This comparative approach provides insight into the assets and limitations of each technique for controlled Ga₂O₃ synthesis.
[1] J. Y. Tsao et al., “Ultrawide-Bandgap Semiconductors: Research Opportunities and Challenges,” Advanced Electronic Materials, vol. 4, no. 1, p. 1600501, 2018, doi: 10.1002/aelm.201600501.
[2] M. Bosi, P. Mazzolini, L. Seravalli, and R. Fornari, “Ga 2 O 3 polymorphs: tailoring the epitaxial growth conditions,” Journal of Materials Chemistry C, vol. 8, no. 32, pp. 10975–10992, 2020, doi: 10.1039/D0TC02743J.
[3] H. Guillon and S. Bonnafous, “Vaporization of Solid or Liquid Organic, Organometallic or Inorganic Compounds,” no. Gases&Instrumentation, pp. 17–19, Jun. 2008.
[4] G. Hector et al., “Chemical Synthesis of β-Ga2O3 Microrods on Silicon and Its Dependence on the Gallium Nitrate Concentration,” Inorg. Chem., vol. 59, no. 21, pp. 15696–15706, Nov. 2020, doi: 10.1021/acs.inorgchem.0c02069.
Short Bio/CV
Originally from the Amazonian region of Peru. I earned my Bachelor’s in Engineering physics at Universidad Nacional de Ingeniería in Lima, Peru. After conducting research in Peru and abroad on soft robotics, plasma physics, and material science, I moved into industry as an R&D Engineer in the automotive sector, designing and testing eGlasses. Three years later, I pursued the Erasmus Mundus Master in Nanoscience and Nanotechnology, specializing in nanoelectronics at KU Leuven (Belgium) and TU Dresden (Germany). Since 2023, I have been a PhD candidate at Université Grenoble Alpes, working across LMGP and Institut Néel as part of the cross-disciplinary program PowerAlps from.
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Contact : deborah.verger@grenoble-inp.fr

Christophe VALLEE (College of Nanotechnology, Science, and Engineering (CNSE) - University at Albany - SUNY)
2026-06-02 15:00 - 16:00 | Phelma minatec, Salle Z108, Grenoble INP - Phelma, 3 parvis Louis Néel, Grenoble, 38000, France
Le dépôt sélectif par zone (ASD) : de la substitution de la lithographie à son amélioration
Résumé :
Dans cet exposé, nous allons présenter le dépôt sélectif par zone (Area Selective Deposition) et illustrer le fait que ce procédé, initialement développé pour supprimer des étapes de lithographie, peut être aussi utilisé pour améliorer ces étapes.
Dans un premier temps, nous introduirons les différentes façons de faire un dépôt sélectif par zone, puis nous donnerons quelques exemples d’application. Ensuite, nous discuterons des interactions entre ce procédé et des matériaux polymères afin de démontrer que les polymères peuvent être utilisés comme inhibiteurs dans un procédé ASD. De plus, nous montrerons que le procédé ASD peut aussi être réalisé directement sur des polymères, pour améliorer certaines de leurs propriétés telles que leur rugosité de surface et leur résistance à la gravure plasma. Nous finirons en donnant un exemple de dépôt sélectif « vertical » combinant à la fois une gravure sélective du polymère par effet catalytique et un dépôt sélectif par zone.
Short Bio/CV
Christophe Vallée est professeur à l’Université Grenoble Alpes jusqu’en 2020, spécialisé dans les procédés plasma. Il a mené ses recherches au Laboratoire des Technologies de la Microélectronique (LTM) – Polytech Grenoble, ainsi qu’en tant que professeur invité à l’Université de Tsukuba au Japon (2016–2020). En 2020, il y a été nommé premier «TEL Innovation Scientist», soutenu par une dotation de 2,3 millions de dollars pour le développement de technologies avancées au service de l’industrie des semi-conducteurs. Depuis 2022, il est professeur permanent au CNSE de l’Université d’Albany (État de New York). Ses recherches portent sur la gravure plasma, le dépôt plasma et les procédés à l’échelle atomique (ALD, ALE), appliqués à la fabrication de dispositifs semi-conducteurs.
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Contact : deborah.verger@grenoble-inp.fr

Arjun DEY (Paul Scherrer Institute)
2026-06-03 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
Excitation energies from ground-state DMRG on the fuzzy sphere
Résumé :
It has been observed that some eigenvalues of the effective local Hamiltonian built during a ground-state DMRG sweep of a one-dimensional critical chain stay nearly flat across iterations. Those flat levels correspond to true low-energy excitations, giving access to the excitation spectrum at no extra cost. We ask whether the same holds on the fuzzy sphere, a geometry used to study two-dimensional critical theories by mapping them onto a one-dimensional orbital chain. Getting excited states there directly is costly. We find numerical evidence that flat levels appear in the eigenvalues of the effective local Hamiltonian during our sweeps and match the expected low-energy spectrum. The symmetries of the fuzzy sphere and orthogonalization across symmetry sectors introduce additional structure into those eigenvalues, which helps in resolving and assigning the excitations.
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Contact : loic.herviou@lpmmc.cnrs.fr

Timothée PROIX (ETH Zurich)
2026-06-04 11:30 - 12:30 | GIN – Amphi Serge Kampf, Grenoble Institut des Neurosciences (GIN) Bât. Edmond J. Safra, Chemin Fortune Ferrini CHU, La Tronche, 38700, France
Neural manifolds for speech processing
Résumé :
Speech comprehension requires the brain to represent and combine phonetic, lexical, and semantic information across a linguistic hierarchy. Yet how neuronal populations implement these representations and compositions remains unclear. In this talk, I will show how the framework of neural manifolds offers a powerful lens for this question, combining intracranial recordings in the human cortex with population-level analyses and computational modeling.
I will show that linguistic features are encoded as distinct trajectories on low-dimensional manifolds, which can be resolved analytically by fitting recurrent neural networks directly to the neural data. I will then discuss how these trajectory-based representations are combined across levels, from the composition of phonetic features into syllables, to the interactions between phonetic and semantic representations. Together, these perspectives point toward a population-level mechanism for the representation and composition of speech processing.
Contact : michael.pereira@univ-grenoble-alpes.fr

Aurélien DE LA TORRE (ICMMO, CNRS/Université Paris-Saclay)
2026-06-04 14:00 - 15:00 | DCM – Salle C209, DCM - Bât Chimie Recherche 301 rue de la Chimie, St Martin d'Hères, 38400, France
Designing cycloadditions to enable total synthesis
Résumé :
Asymmetric catalysis is a key topic in organic synthesis, as it allows the formation of new bonds while controlling stereogenic centers, which are inherent to natural products and biologically active substances. On the other hand, dual catalysis is an efficient approach to operate multiple chemical operations through a one-pot process. In this presentation, we will discuss our recent developments in asymmetric catalysis and dual catalysis, as well as their application to a concrete total synthesis
problem.
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Contact : adrien.quintard@univ-grenoble-alpes.fr

Nan TANG (University of Augsburg)
2026-06-04 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
New Macroscopic Windows into Spin Ice : From Emergent Monopoles to Quadrupolar Fluctuations
Résumé :
Spin ice, a representative class of frustrated magnets, provides a rich platform for exploring phenomena such as fractionalized excitations and multipolar degrees of freedom, which remain difficult to access using conventional magnetic probes. In this seminar, I will show how thermodynamic measurements, especially elastic probes, together with spintronics technique (in particular the spin Seebeck effect), can serve as practical detectors of these degrees of freedom.
I will develop this theme via two studies in the pyrochlore oxides Pr2​Zr2​O7​ and Dy2​Ti2​O7​, known as spin ices. First, I will show how bulk thermodynamic measurements, centered around elastic probes, can diagnose quantum spin ice physics in Pr2​Zr2​O7​ [1]. Second, I will discuss how transport-sensitive measurements in an insulator—through the spin Seebeck effect—can access the dynamics of emergent magnetic monopoles in the classical spin ice Dy2​Ti2​O7​ [2]. Together, these two studies demonstrate how lattice-based probes and spintronic tools can be brought to bear on frustrated magnets, providing new routes to detect low-energy degrees of freedom.
In this way, precision thermodynamics and modern transport-sensitive techniques can reveal new physics even in long-studied frustrated magnets, enabling direct comparison with theory through sharp macroscopic signatures.
[1] N. Tang et al., Nat. Phys. 19, 92-98 (2023).
[2] N. Tang et al., preprint, arXiv.2509.18422 (2025).

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Contact : elsa.lhotel@neel.cnrs.fr

Sophie GUERON
2026-06-04 16:00 - 17:00 | Laboratoire IJCLab – Auditorium Pierre Lehmann, Rue Ampère, Orsay cedex, 91898, France
Explorer les isolants topologiques avec la physique mésoscopique
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Toutes les informations sont disponibles sur : https://indico.ijclab.in2p3.fr/event/12406/
Contact : louis.fayard@IJCLAB.INP3.FR

John MARTINEZ (Professeur - Grenoble INP-UGA, Ense3, GIPSA-Lab)
2026-06-05 12:30 - 13:15 | Amphi Minatec, 3 parvis Louis Néel, Grenoble, 38054, France
Un nouveau modèle du frottement… Et un nouveau paradigme ?
Résumé :
Des résultats issus d’une collaboration avec Michelin, dans le cadre du Laboratoire Commun I-TireLab (CNRS, Université de Poitiers, Grenoble INP-UGA, UGA), nous permettront de réfléchir sur le caractère et la nature du frottement. Nous allons présenter un nouveau modèle qui pourrait modifier notre vision personnelle sur le frottement.
Il s’agit d’un modèle macroscopique inspiré des théories liées aux machines à induction. Dans cette présentation, nous illustrerons sa capacité à prédire les forces de frottement dans divers scénarios réels.
À propos de l’intervenant
John Martinez est docteur en Automatique à Grenoble INP-UGA depuis 2005 et enseignant-chercheur depuis 2007. Ses recherches portent sur la modélisation et le contrôle-commande des systèmes mécatroniques, principalement dans des domaines d’application liés à la dynamique automobile, au contrôle optimal des éoliennes et aux vélos électriques intelligents.
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Contact : giant.campus@cea.fr

Soutenance de Thèse de Antoine CURÉ (IRIG / Symmes)
2026-06-08 14:00 - 16:00 | GreEN-ER – Amphi 2A003, 21 avenue des Martyrs, Grenoble, 38000, France
Vers des copolymères à blocs donneur-accepteur π-conjugués à structure et composition précisément définies : caractérisation avancée et stratégies de synthèse
Résumé :
Dans un contexte mondial de crise énergétique et de raréfaction des ressources fossiles, la transition vers les énergies renouvelables constitue un enjeu majeur. Parmi elles, l’énergie photovoltaïque occupe une place importante. Cependant, alors que les panneaux solaires au silicium approchent de leurs limites en rendement et en coûts de production, l’émergence de solutions complémentaires devient nécessaire. Les cellules solaires organiques constituent une alternative intéressante, avec des rendements atteignant 21 % dans des conditions standard en laboratoire en 2026. Elles présentent également de bonnes performances en lumière diffuse et offrent un potentiel de production à faible coût de dispositifs flexibles et recyclables. Toutefois, leur stabilité à long terme reste un obstacle à leur industrialisation. La couche active, composée d’un donneur (polymère) et d’un accepteur (petite molécule), subit au cours du temps une séparation de phase qui dégrade les performances. Malgré les progrès réalisés avec les accepteurs polymères, la viabilité à long terme de ces dispositifs reste à démontrer. ​​​​
​ Depuis le début des années 2020, les matériaux monocomposants sont sérieusement envisagés comme une solution à ces problèmes d’instabilité. Contrairement aux mélanges tout-polymères, ils reposent sur des copolymères à blocs reliant de manière covalente les segments donneurs et accepteurs, limitant leur mobilité relative et la ségrégation de phase. Si les premières études rapportent des résultats encourageants, leur structure et leurs propriétés thermiques restent encore mal comprises. La synthèse et l’étude approfondie de ces systèmes constituent l’objectif de cette thèse. ​​​​
Après un premier chapitre introductif, le deuxième chapitre est consacré à l’étude de deux matériaux modèles : le PTQ10, polymère donneur parmi les plus performants de la littérature, et le PIDTe, un polymère accepteur de structure proche de systèmes connus mais dont la synthèse est simplifiée. Ce travail valide leur pertinence comme système modèle et permet de mettre en place les méthodes de caractérisation utilisées dans la suite de la thèse. Le troisième chapitre explore l’analyse structurale des monocomposants par résonance magnétique nucléaire (RMN). L’utilisation de molécules modèles permet d’identifier les signaux caractéristiques des liaisons entre blocs donneurs et accepteurs et d’estimer le nombre moyen de jonctions dans les chaînes de copolymères. Une approche complémentaire par RMN à diffusion ordonnée (DOSY) est également évaluée afin d’estimer la composition des matériaux. Le quatrième chapitre s’intéresse aux propriétés thermiques des monocomposants. Une méthode basée sur la spectroscopie UV-visible est développée pour suivre les évolutions morphologiques à l’échelle nanométrique à l’état solide. Associée à la diffraction des rayons X en incidence rasante (GIWAXS), à la microscopie à force atomique (AFM) et à la calorimétrie différentielle à balayage rapide (flash DSC), elle permet de comparer la stabilité thermique des monocomposants à celle des mélanges tout-polymères. ​​​​
Enfin, le cinquième chapitre vise à synthétiser des monocomposants de structure mieux définie. La modification du monomère du PTQ10 permet d’obtenir un polymère possédant une fonction réactive terminale unique et une structure régiorégulière. Cette régiorégularité améliore l’organisation des chaînes latérales mais semble perturber celle du cœur π-conjugué, affectant les propriétés optoélectroniques. Différentes stratégies de synthèse de copolymères di- et tri-blocs sont ensuite développées, ouvrant de nouvelles perspectives. ​​​​
En conclusion, cette thèse contribue à une meilleure compréhension des matériaux monocomposants pour les cellules solaires organiques et propose de nouvelles approches d’analyse et de synthèse pour des dispositifs plus stables et performants. ​​​​
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Contact : odile.rossignol@cea.fr

Jean-Claude BESSE (Department of Physics, ETH Zurich, CH-8093 Zurich, Switzerland)
2026-06-09 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Execution of Blind Quantum Computing Primitives on a Modular Superconducting Processor
Résumé :
As a route towards a cluster of interconnected processors in a quantum network, the Quantum Device Lab’s approach to short-range modularity uses small modules with high fabrication yield flip-chip bonded to a common carrier chip. In the first part of this talk, we focus on the hardware realization of this 3D-integrated architecture with indium bump bonds, inter-chip spacing control, and parameter targeting enabling high-fidelity operations 1,2. We then leverage this technology in a two-module processor, with three qubits per node 3. The first module acts as a server generating cluster states as entangled quantum resource. The second module acts as a client, consuming the resource through real-time adaptive measurement basis choice. We demonstrate that the client can implement universal single- and two-qubit gates with local measurements and rotations only. As an example of blind quantum computation, we show results of a measurement-based Deutsch-Jozsa algorithm. We verify that the computation remains private, that is, the server’s state doesn’t reveal the client’s algorithm nor its result. This demonstrates that cloud quantum providers can be set up in a way that they respect the data privacy of their clients 4.
1 Norris et al., EPJ Quant. Tech. 11, 5 (2024) 2 Norris et al., EPJ Quant. Tech. 13, 29 (2026) 3 Dalton et al., PRX Quantum 6, 040365 (2025) 4 Song et al., arXiv:2605.14656 (2026)
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Contact : sem_nano_elec_quantique@listes.grenoble.cnrs.fr

Soutenance HDR de Tristan WAGNER (IRIG / IBS)
2026-06-09 14:00 - 15:00 | IBS – Salle des séminaires, IBS 71 avenue des Martyrs, Grenoble, 38042, France
Characterization of native enzymes to understand how anaerobic microbes impact biogeochemical cycles
Résumé :
Microbes are actors of the biogeochemical cycles, transforming gases, minerals, and biological matter through enzymatic reaction chains. Among them, anaerobic archaea, namely methanogens and methanotrophs, play a key role in converting planetary carbon, nitrogen, and sulfur, impacting the biosphere and providing green sustainable solutions for our modern society. The last fourteen years of my career were devoted to understanding the molecular basis of these microbial transformations, such as methane production or degradation, CO2 and carbon monoxide conversion to biofuels, N2 fixation, and sulfur cycling. Since these enzymes harbor O2-sensitive complicated metallocofactors, most of my work relies on native protein purification from the microbes themselves under strict O2 exclusion. After a brief presentation of my career and PhD project, the presented work summarizes my most renowned breakthrough regarding the elucidation of molecular tricks in carbon, nitrogen, and sulfur metabolisms in methane-generating microbes, including their regulatory networks. Then, the latest research led by my group is introduced with : (i) how methanogens munch on methylated substrates such as methanol and lignin-degradation products, (ii) how an industrial bacterium turns waste gases into biofuels, (iii) the study of a microbial consortia “that burn” methane and ethane without oxygen via a native approach. Finally, I will present the features of my past group and my future laboratory. ​​
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N’oubliez pas de vous munir d’une pièce d’identité.​

Soline BEITONE (PhD Student - LMGP)
2026-06-09 14:00 - 15:00 | LMGP – salle des séminaires, Grenoble INP -Phelma 3 parvis Louis Néel, Grenoble, 38054, France
Development and evaluation of a photocatalytic system to reduce and valorize CO2
Résumé :
This work focuses on the development of a photocatalytic system for CO₂ reduction and valorization, contributing to sustainable carbon conversion strategies. The study investigates Cu₂O nanowire (NW)-based photocatalyst, selected for their visible-light activity, abundance, and low toxicity.
A simple, scalable, and cost-effective fabrication strategy was developed to produce such photocatalyst. To enhance performance and stability, the materials were further engineered through TiO₂ nanoparticle modification, enabling the formation of p–n heterojunctions that improve charge separation, stability and light utilization.
The resulting photocatalysts were evaluated for CO₂ conversion into value-added products and water depollution through dye degradation.
Finally, a life cycle perspective was incorporated to assess environmental impacts, sustainability benefits, and the scalability potential of these photocatalytic systems.
Short Bio/CV
I am a third-year PhD student with a background in materials science and chemistry. My research focuses on photocatalysis and materials development, with an emphasis on green and sustainable approaches.
I am part of the NABIOS team, and my PhD project is integrated into DéfiCO₂, a multidisciplinary initiative aimed at developing and evaluating technological solutions for carbon capture and utilization (CCU).
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Contact : deborah.verger@grenoble-inp.fr

Mahdi ABOU-HAMDAN (LPMMC)
2026-06-10 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
TITRE A VENIR
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Contact : pierre.nataf@lpmmc.cnrs.fr

Kirill NOURSKI (University of Iowa, USA)
2026-06-11 11:30 - 12:30 | GIN – Amphi Serge Kampf, Grenoble Institut des Neurosciences (GIN) Bât. Edmond J. Safra, Chemin Fortune Ferrini CHU, La Tronche, 38700, France
What the insula hears and does : Insights from human intracranial electrophysiology
Résumé :
The human insula is known to be involved in auditory processing, though its detailed response properties remain elusive. Intracranial recordings in human neurosurgical patients provide a unique opportunity to characterize the functional properties of the human insula with high spatiotemporal resolution. Local field potential recordings reveal that posterior insula (InsP) is characterized by larger broadband gamma (30-150 Hz) responses to monosyllabic words compared to anterior insula (InsA). Both subdivisions of the insula generate evoked responses to novel sounds. Single neurons within InsP and, to a lesser extent, InsA, respond to simple sounds in the absence of a behavioral context. InsP and InsA share similar res9ng state functional connectivity profiles with limbic structures. InsP is more closely linked to activity propagated from early auditory cortex, while InsA is more tightly coupled with prefrontal, anterior temporal regions and the amygdala. Clinical case studies identify language and music perception deficiencies associated with insula lesions. Finally, single unit recordings during emergence from general anesthesia reveal a temporal dissociation between reactivation of limbic structures and the insula, the laPer marking the transition to connected consciousness and the capacity to act on commands. Together, these results begin to characterize the insula’s place in the auditory hierarchy, with implications ranging from sensory processing to conscious awareness of our surroundings.
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Contact : julien.bastin@univ-grenoble-alpes.fr

Anne LOPES (I2BC - Gif sur Yvette)
2026-06-11 13:00 - 14:00 | IMAG – Salle de Réunion, 150 place du Torrent, St Martin d’Hères, 38400, France
Emergence of microproteins and de novo genes from noncoding DNA
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Contact : lucie.lamothe@univ-grenoble-alpes.fr

Alexandra COLIN (CEA-Irig/LPCV)
2026-06-12 11:00 - 12:00 | IBS – Salle des séminaires, IBS 71 avenue des Martyrs, Grenoble, 38042, France
Dynamics and Scaling of Competitive Actin Architectures
Résumé :

Cells constantly experience environmental changes requiring a fast adaptation of their different actin structures. However, the mechanisms governing the size and dynamics of these multiple actin structures remain unknown. Decoupling the various parameters that would provide a complete understanding of these mechanisms is very complicated in a cellular context. This is why we have developed a bottom-up approach to identify the key molecular mechanisms that determine the size and coexistence of multiple competing actin architectures. We used a reconstituted system consisting of purified proteins and substrates to localize actin polymerization in microwells, enabling us to work with a limited number of components. With this system, we reconstituted several dynamic actin architectures, competing for a limited pool of protein, over a period of multiple hours. This allowed us to gain key insights into physiological functions related to actin turnover. I will show how we used this system to study the limits of scaling in dynamic structures, as well as the limits of coexistence in actin networks under resource-limited conditions. Finally, I will show how we can recapitulate these results in a complementary cellular system, in which we have demonstrated that an increase in spreading area leads to a decrease in overall turnover, due to a predominance of structures with low turnover.​​​​​
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Les séminaires et soutenances sont ouverts à tous, notez toutefois que l’accès au campus EPN nécessite un avis de rendez-vous. Merci de remplir ce formulaire et de l’adresser, plus de 48h à l’avance, à ce contact.
Pensez à vous munir d’une pièce d’identité le jour de votre visite.

Benjamin LENZ (IMPMC)
2026-06-12 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
Spectroscopic signatures of spin-polarons in quasi two-dimensional correlated materials
Résumé :
The motion of a single hole in a two-dimensional antiferromagnet can lead to the formation of a low-energy quasiparticle, a so-called spin-polaron, which amounts to a bound state of the doped hole and a spin flip. In this talk, I will first introduce the notion of spin-polarons and then discuss spectroscopic signatures of this quasiparticle at the example of two different material classes which both host quasi two-dimensional low-energy physics in their correlated electronic structure.
Illustrated by the Na-doped oxychloride Ca2CuO2Cl2, we will see how the spin-polaron gives rise to “kink” and “waterfall” features in the spectral function of hole-doped cuprates. Employing a numerical workflow comprising density functional theory and cluster dynamical mean-field theory, we will discuss these features in comparison to measurements obtained from angle-resolved photoemission spectroscopy. As a second example, we will see that spin-polaron physics is also relevant in two prototypical iridates, (Ba,Sr)2IrO4, which host an exotic spin-orbital entangled jeff=1/2 ground state. In particular, the characteristic two-peak structure of their optical absorption and optical conductivity curves will be revisited and interpreted in the light of these coherent low-energy quasiparticles.
B. Bacq-Labreuil et al., Phys. Rev. Lett. 134, 016502 (2025)
F. Cassol et al., arXiv:2509.20337; accepted in Phys. Rev. B (2026)
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Contact : serge.florens@neel.cnrs.fr

Soutenance de Thèse de Giovanni OLIVETTI (CEA-Irig / Spintec)
2026-06-12 14:00 - 16:00 | CNRS – Bâtiment A, CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38054, France
Angular Momentum Transfer Between Waveforms in Axisymmetric Geometries
Résumé :
This thesis investigates the role of angular momentum transfer in the coupling between elastic and spin excitations in magneto-mechanical systems.
In axisymmetric geometries, rotational invariance provides the natural framework for the conservation of total angular momentum[1]. In such a case, this quantity unambiguously labels the eigenmodes of the system and constrains their coupling to an external excitation through well-defined selection rules[2]. The manuscript develops this physical picture from a general perspective based on Noether’s theorem, it introduces spin and orbital angular momentum contributions for a generic vector field and proposes an analytical description of magneto-elastic coupling in axisymmetric systems.
This framework is then applied to two complementary experimental platforms realized in the context of this doctoral work. The first combines chiral surface-acoustic excitations with a magnetic vortex texture in a patterned ferromagnetic disk. The second consists of partially suspended axisymmetric YIG microresonators, designed to support both low-loss mechanical motion and confined spin dynamics within the same structure[3]. Together, these two systems provide complementary routes to investigate how elastic and magnetic modes carrying angular momentum can be generated, controlled, and coupled in realistic devices.
In particular, this work demonstrates the controlled excitation and optical mapping of a surface-acoustic vortex by means of spiral interdigitated transducers. It further addresses the stabilization of magnetic vortex textures in micrometer-scale ferromagnetic disks on anisotropic piezoelectric substrates, as well as their positioning at the center of elastic rotation. The coupling strength in suspended axisymmetric YIG microresonators has been evaluated by comparing experimental data with theoretical modeling, indicating a weak-coupling regime. Moreover, the role of weak symmetry breaking has been discussed for the selective excitation of counter-propagating elastic modes that would otherwise be degenerate.
These developments establish several of the physical and technological conditions required to address experimentally the coupling of elastic and spin excitations carrying angular momentum. More broadly, they outline a route toward magneto-elastic platforms in which symmetry can be used as a resource for selective excitation. In this perspective, partially suspended magnetic microresonators may provide a promising route toward strong magnon-phonon coupling under geometrical and symmetry constraints directly relevant for coherent functionalities. In the longer term, such systems could serve as building blocks for mode-selective transducers and hybrid architectures combining magnetic, elastic, and optical degrees of freedom, with possible perspectives for microwave-to-optical coherent transduction[4].
References

Garanin & Chudnovsky, Phys. Rev. B 92, 024421 (2015).
An et al., Phys. Rev. B 101, 060407 (2020).
Heyroth et al., Phys. Rev. Appl. 12, 054031 (2019).
Engelhardt et al., Phys. Rev. Appl. 18, 044059 (2022). ​

Plus d’information
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Pour suivre la soutenance ​​​en visioconférence​ ​​: lien à venir

Access to the CNRS site is restricted. Please contact Olivetti Giovanni​ or Benjamin Pigeau at least 48h before the defense if you need an entry clearance. You just need to communicate your name and surname, and you will receive the entry clearance by email.

Luis Alberto RAZO LOPEZ (Institut Langevin, Paris)
2026-06-15 11:00 - 12:00 | LiPhy – Salle de conférence, LiPhy 140 avenue de la Physique, St Martin d'Hères, 38402, France
Phase retrieval based on intensity-only spatiotemporal wavefront shaping
Résumé :
We introduce a phase retrieval framework based solely on intensity measurements and intensity-only spatiotemporal modulation. Our approach leverages spatiotemporal wavefront shaping to encode phase information into temporally multiplexed intensity signals, which are subsequently decomposed in the Fourier domain. We show that the resulting temporal harmonics correspond to spiral-phase–modulated speckle components, enabling the retrieval of phase information without direct phase-sensitive detection. We derive the harmonic structure induced by a rotating angular aperture mask and demonstrate that each harmonic carries a distinct spiral phase and amplitude weighting governed by a sinc envelope. Based on this structure, we develop an optimization-based reconstruction algorithm that retrieves both the unknown diffuser phase and system scaling without prior knowledge of the optical transfer function. Experimental results confirm accurate reconstruction of diffuser surfaces and aberration correction, including refocusing through digital micromirror device (DMD)-induced distortions.
Contact : dorian.bouchet@univ-grenoble-alpes.fr

Richard HOLZ (School of Mines, Golden, Colorado, USA)
2026-06-15 11:00 - 12:00 | CEA – Salle de séminaire IRIG (104 – bâtiment C3), 17, avenue des Martyrs, Grenoble, 38000, France
Targeting Iron-Sulfur Cluster Biosynthesis in Staphylococcus aureus : Mechanistic Insights into the SUF Pathway
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L’accès au CEA Grenoble nécessite un avis de rendez-vous. Merci d’envoyer la copie de votre pièce d’identité à sandrine.ollagnier@cea.fr, avant le 08 juin 2026.
Pensez à vous munir de cette pièce d’identité le jour de votre visite.

Roger TORMO-QUERALT (Institute of Photonic Sciences (ICFO), Barcelona, Spain)
2026-06-16 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Carbon Nanotube Electromechanical Oscillators: where photons, phonons and electrons meet
Résumé :
Achieving strong mechanical nonlinearities, minimally invasive detection, and control at the few-phonon level is a central challenge in the development of mechanical oscillators for quantum technologies, including quantum information processing (1,2), precision sensing (3), and tests of quantum mechanics (4,5). In our group, we aim to realize these capabilities using suspended carbon-nanotube mechanical oscillators coupled to electronic quantum dots. In this talk, I will present results obtained with a device operating in the exotic dispersive ultrastrong-coupling regime (6,7), where the interaction strength between a nanotube mechanical oscillator and a double-quantum-dot electronic two-level system (DQD-ETLS) exceeds the bare energy of the oscillator. In this regime, we demonstrate a mechanical Kerr oscillator with an anharmonicity exceeding the state of the art for mechanical systems by four orders of magnitude (8). We read out the mechanical states using a superconducting cavity coupled to the square displacement (x²) of the oscillator (8), paving the way towards future quantum non-demolition (QND) cavity-based readout of mechanical Fock states (9). I will also show that the decay and decoherence rates of our ETLS charge qubit outperforms the current state of the art for 2DEG-based systems, reaching the highest coherence values ever measured in a charge-based DQD-ETLS (10).
1 A. D. O’Connell, et al. Nature 464 (2010)
2 Y. Yang, et al. A mechanical qubit, 386 (6723) (2024)
3 F. Pistolesi, et al. Phys. Rev. X, 11, 031027 (2021)
4 M.F. Gely et al., AVS Quantum Sci. 3, 035601 (2021)
5 Oriol Romero-Isart. et, al. Physical Review A, 84 (2011)
6 C. Samanta et al, Nat. Phys. 19 (2023)
7 P. Forn-Díaz et al., Rev. Mod. Phys (2019)
8 C.B. Moller*, R.Tormo-Queralt* (under review) 9 P. Arrangoiz-Ariola, Nature volume 571 (2019)
10 P. Scarlino Phys. Rev. Lett. 122, 206802 (2019)
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Contact : equipe-seminaires-nano@listes.grenoble.cnrs.fr

Mohamed AMDDAH (LPMMC)
2026-06-17 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
Dissipative Dynamics of Phase Slips in SNS Junctions
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Contact : pierre.nataf@lpmmc.cnrs.fr

Soutenance HDR de Rebekka WILD (IRIG / IBS)
2026-06-18 14:00 - 16:00 | IBS – Salle des séminaires, IBS 71 avenue des Martyrs, Grenoble, 38042, France
Molecular insight into the wonderful complex world of protein glycosylation
Résumé :
This research habilitation focuses on the characterization of a class of enzymes – glycosyltransferases – that are involved in the biosynthesis of glycoproteins. It emphasizes the use of cryo-electron microscopy (cryo-EM) to study these enzymes, for which obtaining mechanistic insights remains a challenging task to this day. The presentation will provide an overview of the different types of glycosylation found in humans, along with a detailed description of the biosynthetic pathways of N-linked glycans and glycosaminoglycans. Subsequently, I describe my work over the past ten years, which is divided into two parts : my postdoctoral studies on a central enzyme complex of the N-linked glycosylation machinery and the work of my research team at the Institut de Biologie Structurale focusing on heparan sulfate and chondroitin sulfate biosynthesis. It closes with an overview on ongoing and future projects.​
L’accès au campus EPN nécessite un avis de rendez-vous. Merci d’adresser votre demande à ibs.seminaires@ibs.fr au moins 48h à l’avance.

N’oubliez pas de vous munir d’une pièce d’identité.​

Soutenance de HDR de Andrew GROSS (DCM (équipe BIOCEN))
2026-06-18 14:15 - 16:30 | DCM – Bât Nanobio, DCM 570 rue de la Chimie, St Martin d'Hères, 38400, France
Nanostructured porous frameworks to control and drive bioelectrocatalysis for sensing and energy generation
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Contact : Nathalie.Camerino@univ-grenoble-alpes.fr

Alain WALCARIUS (Laboratoire de Chimie Physique et Microbiologie pour les Matériaux et l’Environnement (LCPME), UMR Université de Lorraine-CNRS 7564, Equipe Chimie et Electrochimie Analytiques, Nancy)
2026-06-19 09:30 - 10:30 | DCM – Bât Nanobio, DCM 570 rue de la Chimie, St Martin d'Hères, 38400, France
Intérêt des membranes de silice à porosité orientée en électrochimie analytique et au delà
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Contact : andrew.gross@univ-grenoble-alpes.fr

Soutenance HDR de Julien PERARD (Irig/LCBM)
2026-06-19 10:00 - 11:00 | DCM – Bât Nanobio, DCM 570 rue de la Chimie, St Martin d'Hères, 38400, France
From iron to biohydrogen: how bacteria are inspiring the biotechnologies of tomorrow
Résumé :
Microorganisms play a crucial role in biotechnologies, enabling the transformation of matter into high-value gases and biomass. At a time when the climate emergency demands a rethinking of our energy models, my work is part of a responsible research approach, aiming to reconcile scientific excellence, environmental sustainability, and economic viability.​
Over the past twelve years, I have dedicated my career to understanding the molecular mechanisms of the Fur and SUF systems (Fe-S cluster biogenesis, bacterial virulence) and to studying nickel insertion into CO dehydrogenase, using integrated structural approaches (SAXS, MALLS, crystallography). Since 2021, I have refocused my research on energy biotechnologies. After a brief overview of my scientific journey, I will detail my projects on developing solutions for BioH₂ production and CO₂ valorization, particularly through the « Bioraffinery » project (combining photofermentation and methanogenesis), inspired by my participation in the 2022 EIC Horizon Prize. I have optimized photobioreactors (PBRs), improving their light efficiency and achieving up to 5 mol H₂/mol of substrate from PLA waste.​
Today, I am working on optimizing microbial strains and culture conditions, as well as integrating circular processes for the joint production of BioH₂/BioCH₄. In collaboration with Génoscope, CEA Tech, and industrial partners, I have developed advanced biorafineries to convert by-products into biofuels.​
My work, at the interface of biophysics, enzymology, and engineering, is part of a decarbonized bioeconomy approach.​
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Contact : alain.farchi@cea.fr

Jonathan HOME (ETH Zürich)
2026-06-19 11:00 - 12:00 | GreenER – Amphi Bergès, GreenER, 21 avenue des Martyrs, Grenoble, 38031, France
Scaling trapped-ion quantum computers
Résumé :
Trapped ions are among the most promising paths to realizing quantum computers, having exhibited the highest fidelity gates and long coherence times. Scaling up will require the adoption of new technologies, and can be facilitated by new approaches. In this talk I will describe recent work from our group in both directions. Firstly I will describe the use of integrated optics to deliver light to multiple zones of an ion trap chip in scalable manner, and give an impression of the new types of control which might be enabled by this approach 1,2,3. I will then introduce a new concept for scaling trapped-ion quantum computers based on microfabricated Penning traps, introducing flexible 2-dimensional ion transport while removing the need for high-voltage radio-frequency fields and thus improving compatibility with standardized chip fabrication 4,5. We have used this to perform sensing of both static and oscillating magnetic and electric fields near the chip surface, and more recently demonstrated multi-qubit gates and control of multi-dimensional arrays of ions.
1 K. Mehta et al. Nature 586, 533–537 (2018)
2 A. Ricci et al. Phys. Rev. Lett. 130, 133201 (2023)
3 C. Mordini et al. Physical Review X 15, 011040 (2025)
4 S. Jain et al. Physical Review X 10, 031027 (2021)
5 S. Jain et al. Nature 627, 8004, pp. 510–514 (2024)
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Contact : michele.filippone@cea.fr

Soutenance de Thèse de Marco BIAGI (IRIG/Spintec)
2026-06-19 14:00 - 16:00 | CEA – Salle de Séminaire IRIG (1005 – 445), Laboratoire Irig/Spintec, salle de séminaire 445, bâtiment 1005, CEA-Grenoble, Grenoble
Exploration of orbital-to-spin conversion materials and integration in 3-terminal spin-orbit torque magnetic tunnel junctions
Résumé :
The development of electrically controlled nanomagnets for spintronic applications, particularly non-volatile magnetic memories (MRAM), is attracting strong interest due to the limitations of CMOS-based memories such as SRAM and eDRAM. Spin–orbit torque (SOT) MRAMs are promising candidates for addressing SRAM specifications; however, current materials still suffer from limited efficiency and high resistivity, leading to unmet write-current requirements. Recently, studies have highlighted orbital phenomena as a potential route to enhance SOT efficiency, owing to their larger magnitudes and availability in a broader set of materials. However, orbital currents do not couple to magnetization in the absence of spin–orbit coupling, requiring an orbital-to-spin conversion layer, which motivates studies of conversion mechanisms and associated physics.
In this PhD work, we evaluate promising orbital/HM/FM material systems for SOTMRAM applications. We present a comprehensive study of Ru/HM/FeCoB and Ta/W/ FeCoB systems, where Ru and Ta act as orbital current sources, while Ta, W, and Pt serve as orbital-to-spin conversion layers. Ru is predicted to exhibit one of the largest orbital Hall angles among transition metals while maintaining low resistivity. Ta, a heavy metal with a large spin Hall effect, is predicted to exhibit an orbital Hall angle approximately one order of magnitude larger than its spin counterpart. When a heavy metal is used as a conversion layer, multiple spin-current contributions can coexist and add linearly to the total effective spin Hall conductivity, potentially enhancing the overall SOT efficiency.
We characterized key parameters relevant to SOT magnetic tunnel junctions (MTJ) devices, including saturation magnetization, effective anisotropy field, and resistivity, and we quantified damping-like (ξDL) and field-like (ξFL) SOT efficiencies as a function of orbital and conversion layer thickness, both in as-deposited and 300°C annealed samples. These metrics are benchmarked against reference HM/FeCoB systems to isolate the effect of the additional orbital layer. For Ru/Ta and Ru/W stacks, limited enhancement ξFL of ξDL is observed relative to reference systems. In contrast, Ru/Pt exhibits a twofold increase in ξDL compared to Pt alone. This difference is attributed to the stronger SOC in Pt, which enables more efficient orbital-to-spin conversion. The independence of ξDL on Ru thickness further suggests an interfacial origin of the orbital contribution in Ru/Pt. However, thermal annealing strongly degrades ξDL, limiting its applicability for SOT-MRAM. In Ta/W systems, we observe a strong enhancement of ξDL by a factor of 4.4 relative to Ta and 3.2 relative to W. A parallel-resistor model indicates that conventional SHE contributions cannot fully account for this increase, pointing to an additional orbital-related mechanism. Extending the study to 400 °C annealing shows that ξDL remains largely stable, indicating good thermal robustness while maintaining perpendicular magnetic anisotropy.
Leveraging these advantages, we further integrate the Ta/W system into SOT-MTJs and benchmark it against standard W-based MTJs. We investigate the pulse-length dependence of the critical switching current and provide a first demonstration of integrated orbital-to-spin conversion in SOT-MTJs. Ta/W devices exhibit switching currents comparable to W-based devices but have a lower switching current density and improved perpendicular magnetic anisotropy stability. Finally, we present a proof-of-concept for vertical non-local switching of SOT-MTJ using orbital torques, simplifying bottom-pinned SOT-MRAM fabrication. Overall, these results demonstrate that orbital physics can be exploited to enhance SOT-MTJ performance, simplify fabrication, and provide a promising route toward scalable bottom-pinned MRAM technologies.
Plus d’information : https://www.spintec.fr/phd-defense-exploration-of-orbital-to-spin-conversion-materials-and-integration-in-3-terminal-spin-orbit-torque-magnetic-tunnel-junctions/
Pour suivre la soutenance ​​​en visioconférence : https://univ-grenoble-alpes-fr.zoom.us/j/98769867024?pwd=[REDACTED]
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