SFP Alpes

Roxane LESTINI & Nicolas OLIVIER (Laboratoire d'Optique et Biosciences, Palaiseau)
2026-02-16 11:00 - 12:00 (Europe/Paris) | LiPhy, Salle de Conférence, 140 rue de la Physique, St Martin d'Hères, 38400
Understanding DNA replication dynamics in the archaea Haloferax volcanii
Résumé :
Archaea provide a simplified yet highly informative model for deciphering the complex regulatory networks governing DNA replication and origin firing. Among them, Haloferax volcanii has a circular chromosome with four active replication origins distributed across a 3.5 Mb DNA molecule and exhibit some distinctive properties, such as a heterogeneous polyploidy, carrying 10–18 copies of its genome.
How these highly polyploid organisms regulate the activation and timing of their multiple replication origins in coordination with cell growth and division remains an open question. To address this question, we developed a multiscale approach, implementing the STORM technique in archaea for the first time, Marker Frequency Analysis by sequencing (MFA-seq) to capture the global replication profile at the population level, and fluorescence in situ hybridization (FISH) to explore ploidy variation.
Our findings reveal, with an unprecedented resolution of ~30 nm, new insights into the spatial regulation of replication foci, demonstrating their organization into clusters. We further investigated DNA replication dynamics under varying growth conditions, revealing a reduction in replication foci number that correlates with decreased replication rates and DNA content. By contrast, altering the replication initiation mode—by inactivating all four replication origins—does not disrupt the overall replication dynamics.
By integrating these techniques, we aim to characterize the replication program in H. volcanii and gain a deeper understanding of its regulation.
Contact : delphine.debarre@univ-grenoble-alpes.fr

Igor ROZHANSKIY (National Graphene Institute, University of Manchester)
2026-02-17 14:00 - 15:00 | CEA – Salle de Séminaire IRIG (1005 – 445), Laboratoire Irig/Spintec, salle de séminaire 445, bâtiment 1005, CEA-Grenoble, Grenoble
Interacting spin physics in 2D : flat bands, SOC renormalization, and chiral textures
Résumé :
Two-dimensional materials and their heterostructures offer a controllable setting where exchange, spin-orbit coupling (SOC), and electron interactions shape the spin-resolved electronic structure and response. This seminar links two recent directions of my work through this common theme.
The first part focuses on van der Waals magnets (chromium trihalides) combined with graphene. Narrow, spin-polarized conduction bands make these systems susceptible to charge-transfer-driven doping and strong correlations. Using DFT-calibrated effective tight-binding models, I will show how flat-band features and longer-range hopping processes determine the low-energy spectrum and favor regimes with heavy, strongly interacting carriers.
​ The second part addresses many-body renormalization of SOC in monolayer transition metal dichalcogenides. Exchange effects can enhance the conduction-band spin-orbit splitting in a density-dependent manner. I will outline ​the underlying mechanism and discuss how it can be inferred from gated transport and quantum-oscillation measurements, including multilayer configurations where valley structure and interlayer coupling provide additional diagnostics.
A short outlook will touch on chiral spin textures, such as skyrmions, and how real-space chirality can contribute to transverse signals, emphasizing possible connections and open questions for 2D material platforms.
https://www.cea.fr/drf/irig/Pages/Animation-scientifique/seminaires/2026_Rozhanskiy.aspx
Contact : admin.spintec@cea.fr

Anton POTOCNIK (IMEC, Belgium)
2026-02-17 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
High-coherence foundry-compatible superconducting qubit platform
Résumé :
The field of superconducting qubit technology has experienced rapid development over the past two decades. Recent advancements in the fabrication, control and measurement of superconducting quantum devices have enabled integration of hundreds of qubits on a single chip. However, the path towards larger-scale integration of thousands of qubits on a chip remains unclear. This talk presents imec’s platform for scalable superconducting qubit fabrication, which is based on foundry-compatible thin film processing 1 and overlay Josephson-junction fabrication 2. The platform enables all-optical superconducting transmon qubit fabrication on 300 mm wafers, achieving near state-of-the-art coherence times, record-low aging and comparable Josephson junction variability to standard shadow-evaporation technique 3. A key focus of this presentation will be the understanding and mitigation of microwave losses induced by various fabricaiton steps such as Ar-milling 4 and oxide removal 6,7 and materials such as -Ta 5 or ultra-high-resistivity silicon. The talk will conclude with an outline of ongoing efforts toward large-scale qubit characterization and control using cryo-CMOS electronics operating near qubits at the mixing-chamber plate of a dilution refrigerator 8.
1 Mongillo, et al., IEDM (2022).
2 Verjauw et al., npj Quantum Information 8, 93 (2022).
3 Van Damme, et al., Nature, 634, 74 (2024).
4 Van Damme, et al., PRA 20, 014034 (2023).
5 Lozano, et al. Mater. Quantum. Technol. 4, 025801 (2024).
6 Verjauw, et al., PRA 16, 014018 (2021).
7 Lozano, et al., Advanced Science 12, e09244 (2025).
8 Acharya, et al., Nature Electronics, 6, 900 (2023).
_
Contact : equipe-seminaires-nano@listes.grenoble.cnrs.fr

Francesco ROSA (Politecnico di Milano, Italy)
2026-02-17 14:00 - 15:00 | CNRS – Salle Louis Weil (E424), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Magnetic and orbital properties of infinite-layer nickelate and cuprate superconductors
Résumé :
Infinite-layer (IL) nickelates recently gained strong interest thanks to their apparent analogies with cuprates, including a square lattice-based structure dominated by superexchange antiferromagnetic interaction and the emergence of superconductivity upon hole doping. X-ray spectroscopies with synchrotron light are a very powerful tool for the investigation of such systems, providing complementary information to the more traditional inelastic neutron scattering. In this seminar, we discuss some of the recent results obtained by our group using both Resonant Inelastic X-ray Scattering (RIXS) and X-ray Magnetic Circular Dichroism (XMCD), mainly focusing on magnetism. RIXS results concern the analysis of dynamic spin excitations (magnons/paramagnons), investigating the effect of hole-doping on them and providing an estimate for the magnetic exchange coupling constants. Results on IL nickelates will be compared to analogous ones on cuprates, highlighting analogies and differences. XMCD analysis is devoted to the static spin order in IL nickelates, reporting the presence of a field induced out-of-plane Ni1+ spin moment. Based on magnetic field- and temperature-dependent measurements, we justify our observations with an out-of-plane canting of in-plane anti-ferromagnetically correlated Ni1+ spins, tentatively attributed to a symmetry lowering of the NiO2 planes.
_
Contact : andrew.fefferman@neel.cnrs.fr

Dmitri KHVESHCHENKO (University of North Carolina)
2026-02-20 11:00 - 12:00 | LPMMC, CNRS - Bat G, salle Roger Maynard G-421, Grenoble
Applied Hall-o-graphy with no strings attached
Résumé :
This discussion aims at ascertaining the true status of the so-called applied-holographic approach to strongly correlated quantum matter. The latter ranges from ‘not even wrong’ for the constructions based on the ad hoc ‘AdS/CMT’ to ‘might be right, albeit for the wrong reason’ for those emerging in the context of phase-space bosonization and the related ‘Hall-o-graphic’ hydrodynamics.The presentation will be made accessible to the wide audience of non-experts and students.
Contact : serge.florens@neel.cnrs.fr

Rolf LORTZ (CNRS-LNCMI, Grenoble)
2026-02-26 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
High temperatures superconductivity with giant pressure effect in 3D networks of boron doped ultra-thin carbon nanotubes in the pores of ZSM-5 zeolite
Résumé :
We report the fabrication of three‑dimensional, interconnected networks of ultrathin carbon nanotubes (CNTs) embedded within the ~5 Å pores of zeolite ZSM‑5 crystals using a controlled chemical vapour deposition (CVD) process. Confinement within these sub‑nanometre channels yields CNTs with strongly one‑dimensional electronic characteristics, including pronounced van Hove singularities in the density of states. By introducing boron dopants during growth, we strategically tune the Fermi level toward a van Hove singularity, as supported by ab initio electronic‑structure calculations. This electronic tuning, combined with the intrinsic 3D connectivity of the CNT–zeolite framework, enables a dimensional crossover from 1D electronic states to a phase‑coherent, bulk superconducting state.
To establish the presence of superconductivity, we employ five complementary experimental probes—electrical resistivity, ac susceptibility, dc magnetization, specific heat, and point‑contact spectroscopy. All measurements consistently indicate a superconducting transition at ambient pressure with a critical temperature Tc in the range of 220–250 K. Simultaneous resistivity and ac‑susceptibility measurements reveal a three‑order‑of‑magnitude drop in resistance accompanied by the onset of a robust Meissner effect with nearly perfect diamagnetic screening. Point‑contact spectroscopy further uncovers a multigap superconducting state, with a dominant gap of approximately 30 meV, in reasonable agreement with expectations from Bardeen–Cooper–Schrieffer (BCS) theory. The differential conductance spectra exhibit clear particle–hole symmetry and evolve smoothly between the tunnelling and Andreev reflection regimes as the contact transparency is varied—behaviour uniquely characteristic of superconducting quasiparticles. Specific‑heat measurements show a distinct anomaly at the transition, reminiscent of signatures observed in high‑Tc cuprate superconductors.
Finally, we find that the application of very modest external pressure further enhances the superconducting transition temperature, pushing Tc above ambient temperature and suggesting that the system remains far from its optimal tuning point. These results collectively point to a new pathway for achieving high‑temperature superconductivity in engineered low‑dimensional carbon‑based materials.
Contact : florence.levy-bertrand@neel.cnrs.fr

Matteo MILANI (ESPCI Paris)
2026-03-02 11:00 - 12:00 | LiPhy, Salle de Conférence, 140 rue de la Physique, St Martin d'Hères, 38400
Rheofluidics: single-drop oscillatory rheology with microfluidics
Résumé :
The measurement of frequency-dependent viscoelastic moduli is of paramount importance in many fields, from material science to biology, and is typically accomplished in bulk materials using commercial rheometers. The trend towards miniaturization in the biotechnology, manufacturing and chemical processing industries has motivated the extension of viscoelastic measurements to microscopic objects with well-defined shape and size such as droplets, vesicles, microcapsules, or even single cells. For instance, local mechanical probes such as AFM nanoindentation can be used to probe single-cell stiffness, and micropipette aspiration probes the interfacial properties of droplets and vesicles. Despite their versatility, these techniques are characterized by complex deformation geometries and a relatively low throughput, which makes them unfit to sample highly heterogeneous populations such as those typical of biological samples. To this end, novel microfluidic approaches have been recently developed to measure the stiffness of cells and droplets flowing through narrow channels. These approaches are well-suited for applications requiring a high throughput, but they lack the fine control of stress and strain required by quantitative mechanical measurements. Here, we present a novel technique called Rheofluidics, which combines the high throughput of microfluidics with the versatility of traditional rheological probes. Like a stress-controlled rheometer, Rheofluidics measures the time-dependent deformation of droplets subject to a well-defined hydrodynamic stress, whose time evolution is controlled by the shape of the microfluidic channel in which the droplets are flowing. To validate this approach and to demonstrate the power of this technique, we study the linear and nonlinear rheology of oil droplets, hydrogel beads and lipid vesicles, extracting their viscoelastic properties with a throughput more than 1000 times higher than that of standard rheology.
Contact : gwennou.coupier@univ-grenoble-alpes.fr

Ran TAO (Institut Néel)
2026-03-02 14:00 - 15:00 | CNRS – Salle Louis Weil (E424), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Magnetic excitations in LuFe2Ge2
Résumé :
The iron-based superconductor YFe2Ge2 (Tc ~ 1.8 K)[1] has attracted interest due to strong electronic correlations[2] and shows enhanced magnetic fluctuations in neutron scattering[3]. Its isoelectronic and isostructural sister compound LuFe2Ge2 orders antiferromagnetically below TN ~ 6.8 K, and in clean crystals shows a resistive superconducting transition below 1 K. We present recent inelastic neutron scattering experiments on LuFe2Ge2 in the ordered and paramagnetic phases. The excitations are modelled with linear spin wave theory, and we note some similarities to previous results in paramagnetic YFe2Ge2.
[1] J. Chen et al., Phys. Rev. Lett. 125, 237002 (2020).
[2] J. Baglo et al. Phys. Rev. Lett. 129, 046402 (2022). B. Xu et al., Proc. Natl. Acad. Sci. U. S. A. 121, e2401430121 (2024).
[3] H. Wo et al., Phys. Rev. Lett. 122, 217003 (2019).
_
Contact : andrew.fefferman@neel.cnrs.fr

Dalila BOUNOUA (LLB)
2026-03-05 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Polarized Neutrons Reveal Altermagnetism in MnF2
Résumé :
Altermagnets constitute a recently identified class of collinear, magnetically compensated materials in which oppositely oriented magnetic sublattices cannot be mapped onto each other another by a primitive lattice translation or inversion operation. Unlike conventional antiferromagnets, altermagnets break time-reversal symmetry. These distinctive symmetry properties give rise to spin-split electronic bands and chirality-split magnon branches, both exhibiting characteristic anisotropic patterns in momentum space, even in the absence of relativistic spin-orbit coupling [1].
Experimental evidence for spin-split electronic bands has been reported in materials such as MnTe and CrSb using angle-resolved photoemission spectroscopy (ARPES) [2,3], while resonant inelastic X-ray scattering (RIXS) has revealed chiral magnon excitations in CrSb [4]. Polarized neutron scattering, however, provides a unique probe of altermagnetism, as it enables a direct characterization of spin-wave excitations and allows both split magnons [5-7] and their associated chirality [8-10] to be measured simultaneously.
In this work, we investigated the chirality-split magnon spectrum of MnF₂ [9] using polarized inelastic neutron scattering (INS). Our measurements reveal, for the first time in MnF₂, a small but clearly resolvable splitting of the magnon branches, primarily driven by long-range dipolar interactions. Polarization analysis on a magnetically domain-biased sample further uncovers a finite chiral contribution to the neutron scattering cross section, which reverses sign between the two split magnon modes. These observations provide direct spectroscopic evidence of altermagnetism in MnF₂.
[1] G. L. Smejkal et al., Phys. Rev. X 12, 040501 (2022).
[2] J. Krempasky, et al., Nature 626, 517–522 (2024).
[3] S. Reimers et al., Nat. Comm 15, 2116 (2024), G. Yang et al. Nat Commun 16, 1442 (2025).
[4] N. Biniskos et al., Nat Commun 16, 9311 (2025).
[5] Z. Liu Phys. Rev. Lett. 133, 156702 (2024).
[6] Q. Sun et al., Phys. Rev. Lett. 135, 18 (2025).
[7] A. K. Singh et al., arXiv:2511.16086.
[8] P. A. McClarty et al., Phys. Rev. B 111, L060405 (2025).
[9] Q. Faure at al., arXiv:2509.07087 (under review).
[10] J. Sears et al., arXiv:2601.04303v1

Contact : elsa.lhotel@neel.cnrs.fr

Kilian FRABOULET (Max Planck Institute Stuttgart)
2026-03-06 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
Competing orders in many-electron systems: a renormalization group perspective
Résumé :
The renormalization group is an established approach to study quantum many-body systems, and this applies especially to one of its modern implementations known as the functional renormalization group (fRG). In particular, the fRG constitutes a flexible and unbiased tool for the study of competing orders. In this talk, I will outline recent progress in this direction for correlated electron systems. To this end, I will first discuss the competition between antiferromagnetism, charge density waves and superconductivity in the 2D Hubbard model, thus making a connection with high-temperature superconductors. The special role of bosonization methods will be emphasized along the way. I will also show how the fRG can be combined with dynamical mean-field theory to treat strongly interacting regimes, with a focus on d-wave superconductivity. As a next step, I will increase the complexity of the model by including non-local interactions and discuss unconventional superconductivity in an extended Hubbard model with a connection to moiré materials. Special consideration will also be given to the treatment of retarded interactions with electron-phonon couplings. Finally, I will highlight recent fRG studies of quantum criticality in Dirac materials, with a connection to graphene.
Contact : serge.florens@neel.cnrs.fr

Marek BARTKOWIAK (Paul Scherrer Institut)
2026-03-09 14:00 - 15:00 | CNRS – Salle Louis Weil (E424), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Spin-orbit control of antiferromagnetic domains without a Zeeman coupling
Résumé :
Encoding information in antiferromagnetic (AFM) domains is a promising solution for the ever growing demand in magnetic storage capacity. The absence of a macroscopic magnetization avoids crosstalk between different domain states, enabling ultrahigh density spintronics while being detrimental to the domain detection and manipulation. Disentangling these merits and disadvantages seemed so far unattainable. We report evidence for a new AFM domain selection mechanism based on non Zeeman susceptibility anisotropy induced by the relative orientation of external magnetic fields to the k-domains. Consequently, the charge transport response is controlled by the rotation of the magnetic field and a pronounced anisotropic magnetoresistance is found in the AFM phase of bulk materials Nd$_{1−x}$Ce$_x$xCoIn$_5$. Our results and the domain switching theory indicate that this constitutes a new effect which might be universal across multiband materials. It provides a novel mechanism to control and detect AFM domains, opening new perspectives for AFM sprintronics.
Contact : andrew.fefferman@neel.cnrs.fr

Synergies in High Resolution Spectroscopy workshop (HIRES2026)
2026-03-10 00:00 - 2026-03-13 23:59 | ILL – Salle de Séminaire (SB-036), ILL 71 avenue des Martyrs, Grenoble, 38042, France
The workshop will bring together researchers in the fields of neutron spin-echo, backscattering, and time-of-flight (TOF) spectroscopy. It aims to highlight the strengths and synergies of these techniques, while also showcasing their interplay with other non-neutron-based methods.
Participation is not limited to neutron experts, users of complementary techniques who wish to expand their research toward neutron scattering are also warmly welcome.
Abstract submission deadline is 30 November 2025.
For full details please visit the website of the workshop: https://workshops.ill.fr/e/HIRES2026

If you have any questions don’t hesitate to contact the Organising Committee by e-mailing to hires@ill.fr

Synergies in High Resolution Spectroscopy workshop (HIRES2026)
2026-03-10 08:30 - 2026-03-13 12:00 | ILL 4, Grenoble, 38000, France
The workshop will bring together researchers in the fields of neutron spin-echo, backscattering, and time-of-flight (TOF) spectroscopy. It aims to highlight the strengths and synergies of these techniques, while also showcasing their interplay with other non-neutron-based methods.
Participation is not limited to neutron experts, users of complementary techniques who wish to expand their research toward neutron scattering are also warmly welcome.
For full details please visit the website of the workshop : https://workshops.ill.fr/e/HIRES2026
If you have any questions don’t hesitate to contact the Organising Committee by e-mailing to hires@ill.fr
_
Contact : HIRES2026@ill.fr

François PARMENTIER (Laboratoire de physique de l'école normale supérieure)
2026-03-10 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Quantized heat flow in the Hofstadter butterfly
Résumé :
When subjected to a strong magnetic field, electrons on a two-dimensional lattice acquire a fractal energy spectrum called Hofstadter’s butterfly. In addition to its unique recursive structure, the Hofstadter butterfly is intimately linked to non-trivial topological orders, hosting a cascade of ground states characterized by non-zero topological invariants. These states, called Chern insulators, are usually understood as replicas of the ground states of the quantum Hall effect, with electrical and thermal conductances that should be quantized, reflecting their topological order. The Hofstadter butterfly is now commonly observed in van-der-Waals heterostructures-based moiré superlattices. However, its thermal properties, particularly the quantized heat flow expected in the Chern insulators, have not been investigated, potentially questioning their similarity with standard quantum Hall states. Here we probe the heat transport properties of the Hofstadter butterfly, obtained in a graphene / hexagonal boron nitride moiré superlattice. We observe a quantized heat flow, uniquely set by the topological invariant, for all investigated states of the Hofstadter butterfly: quantum Hall states, Chern insulators, and even symmetry-broken Chern insulators emerging from strong electronic interactions. Our work firmly establishes the universality of the quantization of heat transport and its intimate link with topology. A. Zhang, et al., arXiv:2601.05694 (2026)
Contact : equipe-seminaires-nano@listes.grenoble.cnrs.fr

Tymoteusz TULA (LPMMC, CNRS, Grenoble)
2026-03-11 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
One-to-one correspondence between two-point correlators and entanglement in magnetic systems
Résumé :
There are multiple measures of multipartite entanglement — including entanglement in thermal mixtures — currently used to study many-body interacting systems. Recently, Quantum Fisher Information has been proposed as a multipartite entanglement measure that can be connected to experimentally accessible observables. In this talk, I will present our recent findings about a one-to-one correspondence between two-point correlators and a certain general class of Heisenberg-like Hamiltonians and wavefunctions. This is a foundation of our claim that a mapping from finite-temperature observables to any entanglement measure exists for such systems. Furthermore, I will present our results of training a convolutional neural network (CNN) to recognize and predict the entanglement for one-dimensional anisotropic XY and XYZ models, which exhibit an entanglement transition. From our preliminary results we found that entanglement can be accurately predicted by a CNN using both static and dynamical correlators, even when the network is trained on only a fraction of the full dataset or on data from a different system than the one used for prediction. Specifically, when trained on observables from an anisotropic XY model, accurate predictions can be achieved using only about 3% (6%) of the data when employing dynamical two-point correlators (structure factors) for learning.
Contact : pierre.nataf@lpmmc.cnrs.fr

Soutenance de Thèse de Subham SENAPATI (IRIG / Spintec)
2026-03-11 14:00 - 16:00 | CEA – Salle de Séminaire IRIG (1005 – 445), Laboratoire Irig/Spintec, salle de séminaire 445, bâtiment 1005, CEA-Grenoble, Grenoble
Spin-orbit torque based magnetic memories evaluation for cryogenic applications
Résumé :
The rapid development of cryogenic computing platforms, including superconducting electronics, quantum information processors, high-performance computing systems, and space applications, has created a demand for memory technologies that operate efficiently, reliably, and scalable at low temperatures. While magnetic random-access memory (MRAM) is a mature and commercially deployed non-volatile memory at room temperature, its behaviour and limitations at cryogenic temperatures remain insufficiently explored, particularly for three-terminal spin-orbit torque magnetic tunnel junctions (SOT-MTJs). This thesis presents a comprehensive experimental and modelling study of SOT-based magnetic memories operated from room temperature (300 K) down to liquid-helium (4 K) temperatures. A dedicated cryogenic characterisation framework is developed to extract magnetic parameters, quantify switching statistics, and evaluate write performance under both quasi-static and sub-nanosecond pulsed conditions. Temperature-dependent measurements reveal enhanced magnetic anisotropy and thermal stability at low temperatures, accompanied by non-trivial trends in critical switching current. By combining experiments with micromagnetic simulations incorporating temperature-dependent material properties and transient Joule heating, this work demonstrates that self-heating remains a dominant factor during write operations, especially at cryogenic bath temperatures. Beyond conventional SOT-MRAM, complementary approaches including optimised spin-transfer torque devices and voltage-gate-assisted SOT switching are investigated. They show that controlling retention via storage layer thickness is a relevant strategy to decrease write current while electric-field control of anisotropy enables efficient modulation of switching across a large temperature range. Overall, this thesis establishes both the physical limitations and technological potential of SOT- and voltage-gated SOT-based MRAM as viable candidates for future cryogenic memory systems.
https://www.cea.fr/drf/irig/Pages/Animation-scientifique/theses/2026_Senapati.aspx
Contact : admin.spintec@cea.fr

Klaus MØLMER (Niels Bohr Institute, University of Copenhagen)
2026-03-17 14:00 - 15:00 | CNRS – Salle René Pauthenet (J229), CNRS – LNCMI, 25 avenue des Martyrs, Grenoble, 38000, France
Quantum optics with radiation on the move
Résumé :
With the scaling of quantum technologies to many separate material quantum components, we may have to couple these systems by propagating quantum radiation, in the form of light, microwaves or phonons. There are, however, rather fundamental obstacles to the treatment of propagation of quantum radiation and its interaction with matter. These obstacles include the general multimode character of propagating fields and the duration and spatial extent of useful light and microwave pulses. The talk will review a recent theoretical approach to deal theoretically with these obstacles, and it will present examples of new, unforeseen, possibilities for easy preparation and manipulation “on the fly” of quantum states of light and matter.
Coffee and croissants will be offered after the colloquium in front of the room !
Personne à contacter : Michele Filippone (michele.filippone@cea.fr)

Rebeca RIBEIRO (C2N, Paris-Saclay)
2026-03-19 14:00 - 15:00 | CNRS – Salle Rémy Lemaire (K223), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Twist-Angle-Controlled Anomalous Gating in Bilayer Graphene/BN Heterostructures
Résumé :
Anomalous gating effects—such as gate ineffectiveness and pronounced hysteresis—have been observed in graphene-based systems encapsulated in boron nitride (BN) and linked to a possible ferroelectric state. However, their origin, stability, and reproducibility remain under debate. During this talk, I will present charge transport experiments in dual-gated, dynamically rotatable van der Waals heterostructures based on bilayer graphene encapsulated in BN. Remarkably, the angular degree of freedom acts as an ON/OFF switch for the anomalous gating response. We show that the angular alignment between the two BN layers is the key parameter governing these effects. Both gate ineffectiveness and hysteresis are highly sensitive to small angular changes, and they clearly change in behavior, which we classify into three distinct regimes.
Contact : florence.levy-bertrand@neel.cnrs.fr

ATTENTION !!! Séminaire reporté. Initialement prévu le 30 mars !!! - Bjoern WEHINGER (ESRF)
2026-03-20 13:30 - 14:30 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
Neutron and x-rays scattering on quantum magnets at high pressures and low temperatures
Résumé :
Application of external pressure acts as clean tuning parameter of inter-atomic distances and bond angles and therefor allows for precise control of magnetic interactions in condensed matter. Extreme conditions can thus be used to stabilize novel quantum phases and drive systems close to quantum criticality where new and exciting phenomena are expected. Within this seminar I will show how recent advances in neutron and x-ray scattering allows to access fingerprints of quantum correlations and present novel results on quantum magnets at the extreme.
_
Arno Hiezz (College 4 Secretary)
External visitors may ask for a site access to tellier(at)ill.fr

Stéphanie ROCCIA (LPSC-CNRS/UGA, GRENOBLE)
2026-03-23 14:00 - 15:00 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
The search for neutron electric dipole moment at PSI
Résumé :
The Universe and its history are simultaneously very well understood and still a big mystery. We have amazing tools from satellites to
observatories to weight the universe over its history. But the components of the Universe can simply not yet be explained by physicists. To get the full picture, we need to identify and understand the interactions at play throughout the life of the Universe. This is the meeting point between particle physics and cosmology. At this meeting point stands the neutron, a common particle that we can uniquely use in high precision experiments.
I will present how experiments searching for a permanent electric dipole moment of the neutron (nEDM) aim at discovering new sources of CP violation beyond the Standard Model of particle physics and understanding the origin of the matter-antimatter asymmetry of the Universe. The quest for the neutron electric dipole moment started more than sixty years ago. In recent experiments, polarized ultra-cold neutrons are stored in material bottles.
I will present the ongoing efforts at the Paul Scherrer Institute in Switzerland where the n2EDM spectrometer has taken the first “physics data” in 2025. A large fraction of this dataset is dedicated to measurements of the UCN spectrum. I will present the newest UCN spectroscopy techniques that were recently published and the reasons for the importance of a deep understanding of the UCN spectrum.
—
Hanno Filter (College 3 Secretary)
External visitors may ask for a site access to tellier(at)ill.fr
Zoom link : https://ill.zoom.us/j/98964195699?pwd=[REDACTED] – Password : [REDACTED]

Jacopo DE NARDIS (Cergy Paris University)
2026-03-27 11:00 - 12:00 | LPMMC – salle Roger Maynard (G421), CNRS - LPMMC 25 avenue des Martyrs, Grenoble, 38042, France
Anticoncentration of Wave Functions and Information-Protected Phases in Noisy Quantum Chaotic Systems
Résumé :
I will present recent results on noisy quantum chaotic dynamics, with a particular focus on wave-function anticoncentration—characterized, for instance, through bitstrings output distributions—and on Information-protected phases that persist at finite circuit depth.
Contact : serge.florens@neel.cnrs.fr

Sander VAN SMAALEN (Laboratory of Crystallography, Bayerisches Geoinstitut, University of Bayreuth)
2026-03-30 14:00 - 15:00 | CNRS – Salle Louis Weil (E424), CNRS - Institut Néel 25 avenue des Martyrs, Grenoble, 38042, France
Chiral charge density waves in EuAl4 and related compounds
Résumé :
The BaAl 4 structure type has centrosymmetric, tetragonal symmetry, I4/mmm, with three crystallographically independent atom sites: Ba, Al1 and Al2. Solid solution series RAl 4-x Gax (R= Eu, Sr, Ca, Ba; 0 < x < 4) crystallize in this structure type [1], where Ga preferably occupies the Al2 site. Accordingly, complete chemical order is found for x = 0, 2, 4. Incommensurate charge-density waves (CDWs) have been observed in several of these ordered compounds. For the other values of x, lack of chemical order leads to suppression of the CDW transition. At much lower temperatures (T = 10–30 K) magnetic order appears for the compounds with magnetic Eu atoms. Here, we present the crystal structures of the incommensurate CDWs of EuAl 4 , EuAl 2 Ga2 and SrAl 4 . In particular, the symmetry of the CDWs is analyzed in view of x-ray diffraction data (present data [2–5]), and results of transmission electron microscopy (TEM), density functional theory (DFT) calculations and inelastic x ray scattering (IXS) from the literature [6–8].
References :
[1] M. Stavinoha et al., Phys. Rev. B 97, 195146 (2018). Charge density wave behavior and order-disorder in the antiferromagnetic metallic series Eu(Ga1-x Al x )4 .
[2] S. Ramakrishnan et al., IUCrJ 9, 378–385 (2022). Orthorhombic charge density wave on the tetragonal lattice of EuAl 4 .
[3] S. R. Kotla et al., Phys. Rev. B 112, 064113 (2025). Broken inversion symmetry in the charge density wave phase in EuAl 4 .
[4] S. Ramakrishnan et al., Phys. Rev. Research 6, 023277 (2024). Non-centrosymmetric, transverse structural modulation in SrAl 4 , and elucidation of its origin in the BaAl 4 family of
compounds.
[5] H. Agarwal et al., Phys. Rev. B 111, 155144 (2025). I-centered versus F-centered orthorhombic symmetry and negative thermal expansion of the charge density wave of EuAl2 Ga2 .
[6] H. Ni et al., Phys. Rev. Mater. 8, 104414 (2024). Real-space visualization of atomic displacements in a long-wavelength charge density wave using cryogenic 4D-STEM.
[7] A. N. Korshunov et al., Phys. Rev. B 110, 045102 (2024). Phonon softening and atomic modulations in EuAl 4 .
[8] F. Z. Yang et al., Nature Commun. 16, 10401 (2025). Incommensurate Transverse Peierls Transition and Signature of Chiral Charge Density Wave in EuAl4
Contact : andrew.fefferman@neel.cnrs.fr

Simon PONTON (chargé de recherche CNRS - SIMaP)
2026-03-31 14:00 - 15:00 | LMGP – salle des séminaires, Grenoble INP -Phelma 3 parvis Louis Néel, Grenoble, 38054, France
Development of the combinatorial approach for the CVD thin film deposition process : Multiphysics coupling and machine learning
Résumé :
The combinatorial approach applied to chemical vapor deposition processes integrating high-throughput experiments, computational simulations, and machine learning seems to emerge as a transformative paradigm to accelerate the discovery of novel materials. Through systematic gradient explorations, large-scale datasets can be generated to deepen our understanding of process-structure-property relationships. Machine learning models, trained on experimental and simulated data enable rapid prediction and identification of high-potential solutions, thereby guiding future experiments and simulations. The synergy not only reduces the time or cost associated with material discovery but also unlocks access to previously unexplored regions of the materials space.
Short Bio/CVMy academic journey began in Grenoble, where I studied chemistry before developing a keen interest in materials sciences, particularly nanostructures and their processing. Driven by a desire to unravel the underlying mechanisms, I started my PhD in Toulouse, between the CIRIMAT and LGC. There, I expanded my expertise in chemical engineering and Multiphysics simulation. After nearly two years of postdoctoral research, I sought to broaden my research perspective and joined Polytechnique Montréal in the chemical engineering section for two postdoctoral positions that led to an associate professor role. However, my longing for French cheese proved irresistible, I successfully secured a position at CNRS and joined SIMaP in February 2026.
Contact : deborah.verger@grenoble-inp.fr

Soutenance de Thèse de Simon VERNIER
2026-04-01 14:00 - 16:00 | Phelma minatec, Salle Z108, Grenoble INP - Phelma, 3 parvis Louis Néel, Grenoble, 38000, France
Optimisation et caractérisation avancée de couches minces de zircone stabilisée à l’yttrine par dépôt chimique d’organométalliques en phase vapeur pour des cellules électrochimiques à oxydes solides
Résumé :
Notre consommation énergétique et l’électrification de notre production afin de la décarboner. Le développement des énergies solaire et éolienne est cependant freiné par leur défaut principal : leur intermittence. Le stockage saisonnier de l’énergie sous forme d’hydrogène est une solution prometteuse pour pallier à ce défaut. EPISTORE est un projet de recherche européen visant au développement d’une cellule électrochimique à oxydes solides (SOC), réversible, en couche mince, basse température (< 500°C). Ces dispositifs sont en effet particulièrement pertinents pour la conversion électricité-gaz.
Cette thèse, dans le cadre d’EPISTORE, projet du programme de recherche et d’innovation Horizon 2020, vise au développement de couches minces de zircone stabilisée à l’yttrine (YSZ) pour servir d’électrolyte pour ces SOCs. Le YSZ, contenant 8 mol% d’yttrine (8YSZ) est un matériau déjà largement utilisé comme électrolyte dans les dispositifs électrochimiques en céramique. Ses propriétés lui permettent de conduire efficacement les ions oxygènes tout en formant une barrière électronique. L’étude des couches minces de YSZ fabriquées au cours de cette thèse doit permettre d’évaluer la pertinence de réduire la quantité d’yttrine dans le matériau. En effet, les travaux publiés sur le sujet suggèrent qu’une concentration de 3 mol% ou 4 mol% d’yttrine pourraient améliorer les propriétés mécaniques, vitales pour des dispositifs en couches minces.
Ce travail détaille l’optimisation de la synthèse de ces films par dépôt chimique en phase vapeurs d’organométalliques (MOCVD) puis la caractérisation avancée de ces échantillons, non seulement structurellement et morphologiquement (XRD, TEM, SEM, Raman…) mais aussi de leurs propriétés électriques via de la spectroscopie d’impédance électrochimique (EIS) ou mécaniques via nanoindentation et tests de déformation. Une nouvelle technique d’observation directe de la diffusion ionique impliquant des traceurs isotopiques et de la spectroscopie Raman a aussi été adaptée à ce matériau pour la première fois.
Les résultats obtenus suggèrent que l’emploi de 3YSZ et 4YSZ à basse température (< 500 °C) permettent d’obtenir des performances électrochimiques équivalentes ou supérieures au 8YSZ. Un effet positif de ce changement de concentration sur les propriétés mécaniques des films n’a cependant pas été démontré.
Contact : deborah.verger@grenoble-inp.fr

Rajeesh KUMAR N (Research Associate, Experimental Physics IV – Solid State Physics, Ruhr-Universität Bochum, Germany)
2026-04-07 11:00 - 12:00 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
Magnetism and spin dynamics of a weakly interacting rare-earth stretched diamond lattice
Résumé :
In condensed matter physics, a quantum-disordered ground state is characterized by the absence of long-range order down to absolute zero temperature, where the disorder is driven by quantum fluctuations that persist even at T=0. On the other hand, the magnetism of rare-earth materials is particularly intriguing as it originates from their localized 4f electrons, which exhibit strong spin–orbit coupling, pronounced magnetic anisotropy, and relatively weak exchange interactions between magnetic ions. These unique characteristics, when combined with suitable lattice geometry, can give rise to a wide variety of unconventional magnetic ground states.
A diamond magnetic lattice is a bipartite network and in its ideal form, does not exhibit geometric frustration. However, “stretched” diamond lattices have recently gained attention where frustration can emerge due to competition between nearest-neighbor (J1) and next-nearest-neighbor (J2) exchange interactions, despite preserving the bipartite nature. In this context, we investigate the magnetic ground state of the rare-earth molybdate compound Na5Yb(MoO4)4, which crystallizes in a stretched diamond magnetic lattice. This compound can be viewed as a complex derivative of the conventional scheelite- type ABO4 structure, crystallizing in the tetragonal space group I41/a. The magnetic lattice in Na5Yb(MoO4)4 is highly unusual, featuring a remarkably large nearest-neighbor Yb–Yb separation of approximately 6.3 Å, in contrast to previously studied stretched-diamond systems where the J1 distance typically lies in the range of 3–5 Å and is predominantly governed by superexchange interactions. Furthermore, the next-nearest-neighbor (J2) Yb–Yb distance exceeds 9 Å, significantly weakening the J2 exchange interactions. As a result, magnetic frustration arising from competing J1–J2 exchange is significantly suppressed in Na5Yb(MoO4)4, distinguishing it from other frustrated diamond-lattice systems.
We employ neutron and synchrotron X-ray diffraction to elucidate the structural details of Na5Yb(MoO4)4. The magnetic properties and ground state are investigated using bulk magnetic susceptibility measurements, specific heat studies, and muon spin relaxation (μSR) experiments. In addition, density functional theory calculations within the DFT+U framework are used to provide theoretical support for the experimental findings. Our results establish Na5Yb(MoO4)4 as a rare example of a dipolar quantum paramagnet in which single-ion physics and long-range dipolar interactions dominate, while exchange interactions are suppressed to the millikelvin energy scale.
Reference
1. N. D. Kelly et al., Physical Review Materials 6, 044410 (2022).
2. A. Chauhan et al., Physical Review B 108, 134424 (2023).
3. J. Kumar et al., Physical Review B 111, 014411 (2025).
4. T. Arh et al., Nat. Mater. 21, 416 (2022).

College 5B Secretary
Alberto Rodriguez Velamazan
External visitors may ask for a site access to Brigitte Dubouloz (dubouloz@ill.fr)

Javier CAMPO (Aragón Nanoscience and Materials Institute (CSIC - Universidad de Zaragoza) Zaragoza, Spain)
2026-04-08 14:00 - 15:00 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
A new magnetic state, “B-Phase”, found in MnSi at Low Temperatures
Résumé :
In cubic chiral magnets, Dzyaloshinskii-Moriya (DM) interactions within the chiral crystal structure result in diverse magnetic textures, including skyrmion lattices (SkL) and chiral soliton lattices, which hold promise for spintronic and magnonic devices. Among these, MnSi has been extensively studied due to the SkL formation in the so-called “A-phase” just below Tc [1]. Recently, it was suggested theoretically that at low temperatures (T), the conical helimagnetic (CH) and forced-ferromagnetic (FFM) phases in MnSi might not be directly connected but separated by another SkL phase, possibly metastable, or a new phase of unknown nature near the critical magnetic field (Bc) [2]. The theoretical prediction of the new SkL phase at low T is in good agreement with the experiments reported in MnSi and Cu2OSeO3 [3,4]. On the other hand, by using careful ac susceptibility measurements at low temperature, we determined the magnetic phase diagrams of oriented crystals of MnSi [5]. A new unexpected region, termed “B-phase”, was observed when the magnetic field was applied along the main diagonal <111>.
To clarify the nature of the “B-phase”, we performed small-angle neutron scattering (SANS) measurements at TAIKAN in J-PARC and transverse field (TF)-μSR experiments at TRIUMF. At low temperatures and fields near Bc, SANS patterns revealed two peaks along the horizontal axis, corresponding to the magnetic Bragg peaks of the CH state. Notably, no diffraction peaks indicative of a six-fold-symmetric SkL were observed. Meanwhile, μSR results showed a distinct internal magnetic field distribution in the “B-phase”, different from those in the CH or FFM phases, suggesting that the “B-phase” could involve a reorientation of Mn helices within the unit cell.
In the presentation, we will discuss these SANS and μSR findings in detail and their implications for understanding the spin texture in the “B-phase”.
References

S. Mühlbauer et al., Science 323, 915 (2009).
V. Laliena and J. Campo, Phys. Rev. B 96, 134420 (2017).
T. Nakajima et al., Sci. Adv. 3, e1602562 (2017).
A. Chacon et al., Nature Phys 14, 936–941 (2018).
M. Ohkuma et al., APL Mater. 10, 041104 (2022).

College 5B Secretary
Alberto Rodriguez Velamazan
External visitors may ask for a site access to Brigitte Dubouloz (dubouloz@ill.fr)

Gonzalo PEREZ-BLASCO (Aragón Nanoscience and Materials Institute (CSIC - Universidad de Zaragoza) - Physics Condensed Matter Dept. Zaragoza, Spain)
2026-04-09 14:00 - 15:00 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
Empirical machine learning for 3He spin-filter polarisation decay
Résumé :
A lightweight, empirical machine-learning framework is presented for predicting the time evolution of the nuclear polarisation of 3He spin-filter cells under realistic neutron beam line conditions. The method bridges the gap between detailed microscopic modelling of polarisation relaxation and purely heuristic correction schemes by combining supervised learning with basic physics-informed constraints on spin relaxation. This strategy ensures physically consistent polarisation forecasts while maintaining computational efficiency and ease of implementation.
The framework is tailored to the limited number of heterogeneous experimental datasets typically encountered during routine instrument operation. Rather than explicitly modelling all relaxation mechanisms, it learns an effective representation of polarisation decay directly from experimental data. Within the domain spanned by the training dataset, the model demonstrates stable predictive performance while preserving the expected exponential relaxation behaviour and accommodating non-linear, history-dependent effects.
The resulting predictions enable reliable, time-dependent corrections of neutron scattering data affected by polarisation efficiency drift. Compared with traditional single-parameter relaxation models, the approach accounts for the combined influence of multiple experimental parameters and their temporal evolution. Although extrapolation beyond the training domain requires careful validation, the method provides an operationally efficient and reproducible tool for polarisation monitoring and correction in realistic experimental environments.

College 6 Secretary
Gabriel Cuello
External visitors may ask for a site access to Brigitte Dubouloz (dubouloz@ill.fr)

Juan Bautista CARDA-CASTELLO (Inorganic and Organic Chemistry Department, Universitat Jaume I, Castellón (Spain))
2026-04-17 14:00 - 15:00 | LMGP – salle des séminaires, Grenoble INP -Phelma 3 parvis Louis Néel, Grenoble, 38054, France
Scientific and Technological Innovations in the Ceramic Industry
Résumé :
The conference “Scientific and Technological Innovations in the Ceramic Industry” will provide a concise overview of recent advances in ceramic materials, processing technologies, and new technological opportunities for the ceramic sector. It will examine the technological and economic relevance of the ceramic industry, together with the key properties that make ceramic materials attractive for advanced uses. Particular attention will be paid to ceramic coating deposition techniques and high-temperature sintering processes, as well as to processing routes such as laser zone melting or physical vapor deposition (PVD), whose application offers new possibilities for the ceramic industry. The lecture will also discuss application fields such as photovoltaics, catalysis, and other functional technologies, which represent expanding areas of interest for the ceramic sector. Overall, the presentation will show how innovation is broadening the industrial scope of ceramics beyond their traditional uses.
Short Bio/CV
Juan Bautista Carda Castelló is a Full Professor of Inorganic Chemistry, Head of the Solid State Chemistry Research Group and Director of the “Ciutat de Vila-real” Chair of Ceramic Innovation at Universitat Jaume I in Castellón (Spain). With a highly distinguished academic, scientific, and institutional career, he has developed an outstanding record in research, teaching, and technology transfer, with more than 300 scientific publications, numerous patents, and extensive participation in national and international research projects. He has supervised more than 35 PhD theses, promoted collaborations with universities and technological centers worldwide, and received several major distinctions for his contribution to science and ceramic innovation. His career has made him a leading figure in the fields of solid-state chemistry and ceramic technology.
—
Contact : deborah.verger@grenoble-inp.fr

Elizabeth TILLY (University of New Mexico)
2026-04-28 14:00 - 15:00 | ILL – Salle de Séminaire (110-111), ILL 50 71 avenue des Martyrs, Grenoble, 38042, France
Directional Detection as a Tool for Rare-Event Searches
Résumé :
Measuring the initial scattering angle of a particle track provides powerful discrimination in rare-event searches and can enhance detector characterization. The Migdal effect–characterized by a nuclear recoil and an electron recoil originating from the same vertex–is an inherently directional signal. In this talk, I will present my work with the Migdal In Galactic Dark mAtter expLoration (MIGDAL) experiment which uses a GEM-based TPC. I will discuss the development of our 3D track reconstruction algorithms and studies exploiting its angular resolution to characterize detector response. I will also discuss measurements of drift properties in negative ion drift gas mixtures, maximizing noble gas components with the aim of improving spatial resolution for MIGDAL Phase II. Together these demonstrate the power and versatility of precise directional track reconstruction for next-generation rare-event searches.
—
Hanno Filter (College 3 Secretary)
External visitors may ask for a site access to tellier@ill.fr

École thématique CNRS : Analyses protéomiques quantitatives
2026-05-18 14:00 - 2026-05-22 13:30 | Domaine du Lazaret, La Corniche, 223 Rue Pasteur Benoît, Sète, 34200, France
Cette école propose un état de l’art des approches de protéomique quantitative, de la préparation des échantillons à l’analyse statistique et bioinformatique des données de spectrométrie de masse.
🔬 Thèmes abordés : quantification relative, quantification d’échantillons complexes et des modifications post-traductionnelles, analyses statistiques, limites méthodologiques et principes FAIR.
Le ➕ : Ateliers pratiques sur les différents outils pour l’identification et la quantification, les statistiques et la bioanalyse
👥 Pour qui ? chercheurs, ingénieurs, biologistes, bioinformaticiens, doctorants et post-doctorants académiques ou privés
📝 Pré-inscriptions et infos 👉 https://et2026.sciencesconf.org/
📩 Contact : et2026@sciencesconf.org
