Willem Boutu participates in the Scientific meeting of the GdR CHALCO 2023 // https://gdrchalco.cnrs.fr/?page_id=1144&lang=fr
DRF Welcomes Participants of the 2025 International Physics Olympiad
On July 22, the DRF (Fundamental Research Division of the CEA) opened its doors to nearly 80 students and mentors taking part in the 2025 International Physics Olympiad (IPhO). The visit offered these young “budding scientists” a chance to explore research laboratories and meet physicists passionate about sharing their work.
The IPhO, created in 1967, is an annual global competition bringing together high school and university students from over 80 countries. The 2025 edition, organized by the French Physical Society, was held at Université Paris-Saclay (École Polytechnique) from July 18–24, gathering around 400 participants.
As part of the event, the DRF welcomed the students to five laboratories at IRFU, IRAMIS, and LSCE, featuring presentations, lab tours, and discussions with researchers — including Willeum Boutu, a physicist at LIDYL specializing in attosecond laser physics and ultrafast light–matter interactions. He shared insights into his work and the latest advances in the field.
“It’s amazing to meet scientists in their own labs and talk so freely about their research,” said Adam from the French team.
Moritz, representing Luxembourg, added: “Visiting labs like LIDYL—linked to the 2023 Nobel Prize in Physics—was a real highlight.”
When curiosity meets passion, inspiration follows. For many of these students, the visit may spark a future in science.
Charge density waves often appear as precursors to exotic quantum phases, such as superconductivity. Understanding how they form in certain materials remains a subject of debate. Now, an international team of scientist, including Optologic team members, have studied these charge density waves by applying, for the first time, a laser technique called high-harmonic generation spectroscopy. This new optical method’s extreme sensitivity can detect subtle asymmetries in the sample’s behavior that eluded earlier techniques. This fundamental knowledge could hold key for the realization of correlated quantum phases (like superconductivity) at room temperature. The technique, reported in Communications Materials, could also be used to study and characterize crystals, 2D materials and nanodevices.
New Approach to Ultrafast Multi-Dimensional Spectroscopy
An international team of researchers from the European XFEL, along with colleagues from the Max-Born Institute in Berlin (partners of OPTOlogic), Universities of Berlin and Hamburg, The University of Tokyo, the Japanese National Institute of Advanced Industrial Science and Technology (AIST), the Dutch Radboud University, Imperial College London, and Hamburg Center for Ultrafast Imaging, have presented new ideas for ultrafast multi-dimensional spectroscopy of strongly correlated solids. This work has now been published in Nature Photonics.
Cartoon view of the key many-body states corresponding to the spectroscopic signal at energies of the LHB, QP and UHB.
The Complexity of Strongly Correlated Solids
“Strongly correlated solids are complex and fascinating quantum systems in which new electronic states often emerge, especially when they interact with light” says Alexander Lichtenstein from Hamburg University and Eu-XFEL. Strongly correlated materials, including high-temperature superconductors, certain types of magnetic materials, and twisted quantum materials, challenge our fundamental understanding of the microcosm. Moreover, they offer opportunities for many exciting applications ranging from materials science to information processing to medicine. For example, superconductors are used by MRI scanners. Understanding the hierarchy and interplay of the diverse electronic states arising in strongly correlated materials is very important.
Challenges of Studying Phase Transitions
At the same time, these materials challenge our experimental and theoretical tools because transformations between these states often involve phase transitions. Phase transitions do not develop smoothly from one stage to the next but may occur suddenly and quickly, particularly when light interacts with the material. How do pathways of charge and energy flow during such a transition? How quickly does it occur? Can light control it and sculpt the electron correlations? Can light bring the material into a state that it wouldn’t find itself in under usual circumstances? Powerful and sensitive devices like X-ray lasers such as the European XFEL in Schenefeld near Hamburg, and modern optical tools of attosecond science (1 attosecond = 10^-18 sec), address these types of questions.
A New Approach to Monitor Ultrafast Charge Motion
In their work, the international team now presents a completely new approach that makes it possible to monitor and decipher the ultrafast charge motion triggered by a short laser pulse illuminating a strongly correlated system. They have developed a variant of ultrafast multi-dimensional spectroscopy, taking advantage of the attosecond control of how multiple colors of light add to form an ultrashort laser pulse. The sub-cycle temporal resolution offered by this spectroscopy shows the complex interplay between the different electronic configurations and demonstrates that a phase transition from a metallic state to an insulating state can take place within less than a femtosecond – i.e. in less than one quadrillionth of a second.
New Tools for Investigating Ultrafast Processes
“Our results open up a way of investigating and specifically influencing ultrafast processes in strongly correlated materials that goes beyond previous methods” says Olga Smirnova from the Max-Born Institute and Berlin TU, awardee of the Mildred Dresselhaus prize of the Hamburg Centre for Ultrafast Imaging, “we have thus developed a key tool for accessing new ultrafast phenomena in correlated solids”.
Reference: Sub-cycle multidimensional spectroscopy of strongly correlated materials, V. N. Valmispild, E. Gorelov, M. Eckstein, A. I. Lichtenstein, H. Aoki, M. I. Katsnelson, M. Yu. Ivanov & O. Smirnova, Nature Photonics (2024)
On December 11th, the consortium of OPTOlogic gathered at ICFO, hosted by Barcelona, to discuss the ongoing progress of their project. In addition to the host institution, partners from Max Born Institute, CEA, Fritz Haber Institute – Max Planck, and LightON were present. This in-person meeting provided an opportunity to thoroughly review the project’s advancements, share the latest research findings, and collectively brainstorm novel theories applicable to their field of study. Furthermore, the consortium engaged in discussions to address challenges encountered within the project and to meticulously plan the subsequent steps necessary to achieve their objectives in the final phase.
As a brief overview, the project aims to gain a comprehensive understanding of light-matter interactions in 2D materials and ultimately control the properties of these materials through light manipulation. Throughout the course of the day, partners actively participated in in-depth discussions and lively interactions, with a particular focus on achieving control of these interactions at attosecond timescales. In greater detail, they delved into studying the dynamic behavior of materials when exposed to ultra-fast pulses of light, exploring various phenomena such as high harmonic generation, trefoil fields, phonons, excitons, electronic structures, logic operations, valleytronics, and more.
To conclude the productive meeting, the consortium visited the lab of the Attosecond and Ultra-Fast Optics research group, led by Jens Biegert. During this visit, the partners gained valuable insights into the state-of-the-art facilities and the cutting-edge science being conducted in direct support of the project’s goals.
Stay ahead of the curve – check out our “News & Events” section for the latest news and events you won’t want to miss.
Light-matter interactions in 2D materials
ICREA Prof at ICFO Maciej Lewenstein is among members selected in this year’s class.
The Board of Directors of Optica (formerly OSA) recently elected 129 members from 26 countries to the Society’s 2024 Fellow Class. Optica selects Fellows based on several factors, including outstanding contributions to research, business, education, engineering, and service to Optica and its community. Thus, ICREA Professor at ICFO Dr. Maciej Lewenstein joins this year’s Fellows Class “for outstanding theoretical contributions to atto-optics, atto-science, quantum optics, and quantum information.”
“Congratulations to the 2024 class of Optica Fellows,” said Michal Lipson 2023 Optica President. “It is a pleasure to honor these members who are advancing our field and society. We are grateful for their exceptional work and dedication.”
Optica recognizes Fellows who have served with distinction in advancing optics and photonics. Specifically, Chair Ofer Levi from the University of Toronto, Canada, led the Fellow Members Committee, which reviewed 216 nominations submitted by current Fellows. Since Fellows can account for no more than 10 percent of the total membership, the election process remains highly competitive. Consequently, the Fellow Members Committee recommends candidates, and the Awards Council and Board of Directors approve them.
Optica will honor the new Fellows at conferences and events throughout 2024.
About Optica
Optica (formerly OSA), Advancing Optics and Photonics Worldwide, promotes the generation, application, archiving, and dissemination of knowledge in the field. Founded in 1916, it leads as the premier organization for scientists, engineers, business professionals, students, and others interested in the science of light. Optica’s renowned publications, meetings, online resources, and in-person activities fuel discoveries, shape real-life applications, and accelerate scientific, technical, and educational achievement.
Peng Ye, CEA partner, attended the Paris Saclay International School on Ultra-fast X-rays Science conference and presented a poster in representation of the project.
The Institute for the Sciences of Light of Paris-Saclay University organizes the “Paris-Saclay Ultrafast X-ray Science School” in collaboration with “The Frontiers of Attosecond and Ultrafast X-ray Science School” of Erice (Italy). This thematic school occurs every other year at Paris-Saclay University, alternating with the School of Erice.
Ultrafast X-ray Science 2022
The 1st edition in France will take place October 10-14, 2022. It aims to provide the audience with a general view of the fundamental concepts and basics of ultrafast X-ray and attosecond science, as well as on a series of applications. It will cover topics spanning from the development of ultrafast light sources of visible, XUV, and X-ray radiation, including High Harmonic Generation and Free Electron Lasers, to the study of quantum systems in different states of matter, in both gas and condensed phases.
The School offers a high-profile training opportunity for newcomers in the field, such as master and PhD students, as well as postdocs and junior researchers. Additionally, it provides a chance to discover the laboratories of Paris-Saclay University in the area of the Sciences of Light. Distinguished lecturers each provide two one-hour lectures on a general topic, scheduled on two different days. Moreover, they also give a seminar describing their own research, thus giving insight into current hot research topics. The lecturers remain available for informal post-course discussions most of the week.
The schedule includes numerous opportunities for informal exchanges, from common meal times (including breakfast) to generous poster sessions. Furthermore, an afternoon focuses on on-campus laboratory visits, and a cultural afternoon in Paris complements the program.
PARIS SACLAY INTERNATIONAL SCHOOL ON ULTRAFAST X-RAYS SCIENCE
In a recently study published in Reports on Progress in Physics, researchers Irénée Frérot, Matteo Fadel and ICREA Prof. at ICFO Maciej Lewenstein, review methods that allow one to detect and characterize quantum correlations in many-body systems, with a special focus on approaches which are scalable.
Maciej Lewenstein gives a brief overview about the study in the following video abstract:
Nobel Prize for Attosecond Pulse Development
Pierre Agostini, Ferenc Krausz, and Anne l’Huillier receive the Nobel Prize “for developing experimental methods that generate attosecond pulses of light for studying electron dynamics in matter.” (Attosecond Pulse Development)
Revolutionizing Electron Dynamics
The three Nobel Laureates in Physics 2023 are being recognized for their experiments, which have provided humanity with new tools for exploring the world of electrons inside atoms and molecules. Pierre Agostini, Ferenc Krausz, and Anne L’Huillier have demonstrated a way to create extremely short pulses of light that can measure the rapid processes in which electrons move or change energy.
Groundbreaking Discoveries in Attoscience
Last October, the Royal Swedish Academy of Sciences announced the laureates of the 2023 Nobel Prize in Physics, naming three ground-breaking scientists in the field of Attoscience, Anne L’Huillier, Pierre Agostini, and Ferenc Krausz for “developing experimental methods that generate attosecond pulses of light for studying electron dynamics in matter.”
Congratulations from the ICFOnians
ICFOnians enthusiastically congratulate these friends and colleagues for their landmark achievements and for the highest recognition for their work that this Nobel Prize implies.
Unveiling Processes Inside Atoms and Molecules
The three laureates share this award in equal parts for their experiments that have produced pulses of light so short that they are measured in attoseconds, thus demonstrating that these pulses can provide images of processes inside atoms and molecules.
Anne L’Huillier’s Overtone Discovery
In 1987, Anne L’Huillier discovered that many different overtones of light arise when transmitting infrared laser light through a noble gas. Each overtone is a light wave with a specific number of cycles for each cycle in the laser light. They occur because the laser light interacts with atoms in the gas, giving some electrons extra energy that they then emit as light. Anne L’Huillier has continued to explore this phenomenon, laying the groundwork for subsequent breakthroughs.
Pierre Agostini’s Attosecond Pulse Breakthrough
In 2001, Pierre Agostini succeeded in producing and investigating a series of consecutive light pulses, with each pulse lasting just 250 attoseconds. At the same time, Ferenc Krausz was working with another type of experiment, one that made it possible to isolate a single light pulse lasting 650 attoseconds.
Enabling Unprecedented Investigations
The laureates’ contributions have enabled the investigation of processes that are so rapid that scientists were previously unable to follow them.
Collaboration and Leadership at ICFO
ICREA Professors at ICFO, Drs. Jens Biegert and Maciej Lewenstein, both lead in this field and collaborate with the laureates both experimentally and theoretically. The 1994 Physical Review A collaboration, noted in the Nobel text, co-authored by Lewenstein, Balcou, Ivanov, L’Huilier, and Corkum, has cited over 5000 times. Similarly, Biegert has made significant contributions through a series of landmark papers in this field, and he has built a world-leading attoscience infrastructure at ICFO, the only one of its kind in Spain. Here, the next generation of attosecond soft x-ray pulses harnesses and applies to advance the frontiers of material physics and chemical imaging.
Contributions of Postdoctoral Researchers
Postdoctoral researchers in the ICFO-Max Plank-Cellex programs over the years, generously funded by Fundación Cellex, have also contributed to the field under the supervision of both ICFO Group Leaders and Prof Ferenc Krausz. Understandably, ICFOnians, fully aware of the significance of this work, have received the news of this year’s award without surprise but with a great deal of enthusiasm.
The Revolutionary Impact of Attosecond Pulses
“Attosecond Pulses of light are a revolutionary tool for basic and applied science since they give us for the first time a camera that is fast enough to acquire crisp images of how and where electrons move,” explains Biegert. “This is important since the motion of electrons determines literally everything, from how a chemical reaction happens, how we metabolize, or how materials and sensors work. Many experimental and theoretical scientists, represented by this year’s laureates, are contributing to this extremely fast-growing new field of science”.
If you want to stay informed about events or news, don’t miss out on our ‘News & Events‘ section!!
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 899794. Funding call: H2020-FETOPEN-2018-2019-2020-01.
#OPTOlogicEU
