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In a study just published in ACS Nano, the team investigated what happens when monolayer MoS₂ — a direct-gap semiconductor just three atoms thick — is stacked with graphene. This combination of two-dimensional (2D) materials reveals a subtle but powerful mechanism: electrical control over light emission without relying on high levels of doping. By carefully tuning the interaction between MoS₂ and graphene, the researchers observed a dramatic suppression of photoluminescence (light emission) from specific exciton species (bound electron-hole pairs), depending on whether the material was isolated or part of a stacked heterostructure. The introduction of graphene changes the game: it enables efficient, voltage-controlled charge transfer, preventing the accumulation of excess carriers in MoS₂ and thus keeping the optical response stable and predictable. The most striking insight? In pristine MoS₂, high doping leads to a superlinear increase in light emission — a kind of optical “amplification” that stops once the system is saturated. This effect disappears completely in the MoS₂/graphene stack, showing that graphene acts as a natural “exciton regulator,” draining away excess charge and suppressing this nonlinearity. Even B-type excitons — typically unaffected by doping due to their ultrafast decay — are modulated by this setup, revealing that charge transfer occurs before excitons can recombine internally. This suggests the presence of a hot-electron transfer channel, a new dimension to 2D material photophysics. Why it matters This work opens the door to more precise control over how atomically thin materials emit light, essential for developing efficient LEDs, photodetectors, and quantum light sources. The use of layered 2D materials to achieve such control, without chemical treatment or structural modification, marks a significant leap forward in optoelectronics and nanophotonics. The SUPERVenice perspective This discovery strengthens Venice’s growing role in frontier materials research. The participation of Ca’ Foscari University through Prof. Domenico De Fazio, member of SUPERVenice, highlights the impact of collaborative, interdisciplinary science rooted in fundamental physics with clear technological implications. The full paper, “Tunable Exciton Modulation and Efficient Charge Transfer in MoS₂/Graphene van der Waals Heterostructures”, is available open-access in ACS Nano. 🔬 Read the paper: ACS Nano DOI

Secure communication is essential to modern digital infrastructure, enabling safe data exchange across global telecommunication networks. As computational capabilities grow, so do threats to classical encryption, prompting the development of advanced cryptographic methods. Quantum Key Distribution (QKD) offers a groundbreaking solution by enabling information-theoretically secure (ITS) key exchange, rooted in the principles of quantum mechanics rather than computational hardness. Unlike traditional methods, QKD remains secure even against adversaries with unlimited processing power. To overcome the distance limitations of direct quantum communication, trusted relay QKD networks have been developed. These networks act as secure extensions to classical systems, facilitating the generation and distribution of cryptographic keys across larger scales. However, due to limited key generation rates, efficient key management is critical, especially when integrating QKD into critical infrastructures. Key management ensures optimal use of resources, addressing challenges like key allocation, storage, and prioritization. The accepted work addresses this need by providing a comprehensive review of key management approaches tailored for trusted-relay QKD networks. The surveyed strategies encompass various aspects of key lifecycle management, such as key generation, storage, routing, prioritization, and expiration, as well as integration with existing security protocols and infrastructure requirements. Through in-depth analysis, the paper aims to identify promising techniques, highlight existing limitations, and outline areas for further research. The ultimate goal is to facilitate the strategic development and deployment of scalable, secure, and efficient QKD networks that can be seamlessly integrated into existing communication infrastructures, paving the way for a quantum-safe future. The work is also the result of a long-term research cooperation between researchers from University of Sarajevo (Department of Telecommunications) Bosnia-Erzegovina, VSB-Technical University of Ostrava (Department of Telecommunications) Czech Republic and Ca’ Foscari University of Venice (Department of Molecular Sciences and Nanosystems) Italy. The full article is available at the following link: https://dl.acm.org/doi/10.1145/3730575

Power MOSFETs are key to modern electronics, enabling efficient power conversion and control in a wide range of applications.  However handling short-circuit events remains a challenge—especially for SiC and GaN devices. The Ferro-Power MOSFET changes the game by integrating ferroelectric materials into the gate, reducing temperature rise and enhancing reliability without modifying the device layout or control electronics. Simulations of a 1.2 kV SiC MOSFET show up to 31% lower temperatures and 42% less current surge during faults, making this a breakthrough for automotive and industrial power systems. With advances in CMOS-compatible hafnium oxide, this innovation is set to shape the future of power semiconductors! #PowerElectronics #MOSFET #SiC #GaN #Innovation #TechBreakthrough #Ferroelectrics #Hafnium Oxide   Check out our paper (in collaboration with Prof. A. Irace and L. Maresca from UniNa):  The Ferro-Power MOSFET: Enhancing Short-circuit Robustness in Power Switches with a Ferroelectric Gate Stack

In 1934 Nobel Prize winner Eugene Wigner predicted the existence of a crystal formed by electrons at low density stabilized by strong electrostatic repulsions. Up to date, this crystal has never been observed. However, it was observed experimentally and explained theoretically in the realm of spherical colloids, nanoparticles with nanometric sizes, and nearly perfect spherical shapes. By contrast, the common belief was that this was not observable for rod-like colloidal particles with a high aspect ratio. This recent study, originating from a collaboration from the experimental group of the CNRS in Bordeaux with a theoretical group at Ca’ Foscari University of Venice led by Prof. Achille Giacometti, showed otherwise. At low density and strong electrostatic repulsions, a solution of nearly monodisperse rod-like colloidal particles tends to form a crystal structure stabilized by a combined minimization of the electrostatic potential and the maximization of the entropy associated with the longitudinal and transversal fluctuation of the particles. This has been unambiguously observed experimentally and supported by numerical simulations. Figure (Left): Two charged rods in water and counterions. Figure (Right): Different liquid crystal phases numerically observed for aspect ratio L/D =10 and different Debye wave number kD (WCA= kD → ∞) The full article is available at the following link: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.134.118101

On January 17, 2025, SUPERVenice, the group of engineering and physics innovators, left a lasting impression at the sixth edition of Professione Scienziate. Held at the Alfa Building on the Ca’ Foscari Science Campus in Venice, the event was a platform to showcase the fascinating and practical aspects of STEM fields to high school students from across the region. This year’s event was particularly successful, with SUPERVenice captivating hundreds of visitors with their engaging and hands-on demonstrations. The SUPERVenice stand drew significant attention, showcasing a range of interactive experiments designed to inspire and educate. Among the highlights: The SUPERVenice team’s innovative approach drew large crowds throughout the event, with students and teachers alike praising the accessibility and excitement of the presentations. Beyond simply entertaining, these demonstrations effectively communicated the practical and transformative power of engineering physics, igniting interest among students who are now considering enrolling in the bachelor’s and master’s programs in Engineering Physics at Ca’ Foscari. The event marked a significant milestone in the orientation efforts aimed at encouraging high school students to pursue STEM careers. SUPERVenice’s ability to bridge complex scientific concepts with engaging and relatable demonstrations solidified its reputation as a leader in fostering the next generation of engineers and physicists. As the enthusiasm from Professione Scienziate fades into memory, SUPERVenice looks forward to welcoming these inspired students to its programs, where they will embark on a journey of discovery and innovation. Event Link: https://www.unive.it/data/agenda/6/96921

Hydrogen-rich materials are paving the way for breakthroughs in superconductivity, but the path to efficiently incorporating hydrogen into these materials has been fraught with challenges. Our recent study, published in the Journal of Molecular Liquids, unveils a transformative method for hydrogen loading using deep eutectic solvents (DES), which promises to revolutionise this field. Led by a collaborative team of researchers from Politecnico di Torino, the Ca’ Foscari University of Venice and other institutions, the study demonstrates how a simple mixture of choline chloride and glycerol can replace the traditionally used ionic liquids for hydrogen incorporation. This innovative approach addresses key issues such as cost, toxicity, and environmental impact while achieving hydrogen concentrations high enough to induce superconductivity in palladium. The concept hinges on ionic gating-induced protonation (IGP), a technique that uses an electric field to drive hydrogen ions into materials. By leveraging the unique properties of DES—low viscosity, biodegradability, and cost-effectiveness—the researchers successfully injected hydrogen into palladium bulk foils and thin films, achieving a stoichiometry of up to PdH₀.₈₉. While partial superconducting transitions were observed in thin films, the study underscores the need for further refinement to ensure a uniform hydrogen distribution within materials. Beyond Palladium: A Vision for the FutureThough the research focuses on palladium as a model system, its implications extend far beyond. The DES-based IGP method could be adapted for a wide range of materials, offering promising applications in hydrogen storage, spintronics, and quantum technologies. This breakthrough aligns with global efforts to develop more sustainable and accessible superconducting technologies at practical pressures and temperatures. This groundbreaking study represents a significant leap forward in material science, potentially heralding a new era of innovation. For more details, you can access the full article in the Journal of Molecular Liquids: https://doi.org/10.1016/j.molliq.2024.126826.

Water exhibits unique properties with respect to other liquids, so-called thermodynamic anomalies, even in its equilibrium state under Earth’s ambient conditions. Finding evidence nowadays in several molecular dynamics simulation studies, a compelling hypothesis for explaining the existence of water’s equilibrium anomalies is the so-called liquid-liquid phase transition (LLPT) between high-density and low-density liquid phases (HDL/LDL) in a supercooled, metastable liquid state. Its origin has been so-far not clarified. On the other hand, water is a polar liquid and, as such, can, in principle, undergo a ferroelectric phase transition, resulting in the setting of macroscopic polarization, under some thermodynamic conditions, even in the absence of an external electric field. By analyzing extensive molecular dynamics simulations and developing a classical density functional theory in mean-field approximation, we unveil not only a link between ferroelectric and liquid-liquid phase transitions, but also the role of ferroelectricity in promoting the LLPT. Our theory treats water as a polar liquid. Grounded in the characteristics of the microscopic dipolar potential interaction and the liquid’s molecules positional disorder, it leads to a free energy expression that supports phase transitions both ferroelectric and liquid-liquid. The setting of macroscopic polarization occurs through a reorientation of molecular dipoles. This research not only characterizes but clarifies the origin of the LLPT and thermodynamic anomalies in water. Understanding the origin of the peculiar behavior of water holds the key to uncovering fundamental mechanisms driving life and Earth’s processes. Our study explains the peculiarities of water while treating it as a generic polar liquid. Although the expression for free energy enabling phase transitions applies universally to polar liquids, its specific coefficients, which determine whether the transitions effectively occur under certain thermodynamic conditions, depend on the microscopic details of the liquid being studied. Our research thus raises significant questions: Could the ferroelectric properties of water, highlighted in this study, influence the natural selection of organisms and Earth’s geological evolution? Is water ‘merely’ a polar liquid with the microscopic characteristics suitable to allow a ferroelectric phase transition close to Earth’s environmental conditions? And what contributes to shaping its microscopic characteristics? The link between liquid-liquid and ferroelectric phase transitions, established in this research, can, moreover, guide targeted experiments to measure the critical point of the liquid-liquid phase transition, one of the unresolved tasks in this field. The methodology exploited in this research has two key strengths. First, it tackles a long-standing scientific issue, such as the LLPT in water, from a clear and groundbreaking perspective, focusing on dipolar degrees of freedom and conceiving a link between ferroelectric and liquid-liquid phase transitions. Second, it combines state-of-art molecular dynamics simulations with an elementary theory, with each being essential to achieve an understanding of the scientific issue. This approach requires and stimulates demonstrative-logical and creative thinking. Ultimately, these two aspects proved to be interconnected. This research work originated independently. Its finalization benefited from the support and collaborative environment provided within the PRIN project “Deeping our understanding of the Liquid–Liquid transition in supercooled water” grant 2022JWAF7Y, involving Prof. Francesco Sciortino (Sapienza University), Prof. Achille Giacometti (Ca’ Foscari University) and Prof. Renato Torre (University of Florence and LENS). Publication: M. G. Izzo, J. Russo, G. Pastore, Proc. Natl. Acad. Sci. U.S.A. 121 (47) e2412456121, https://www.pnas.org/doi/10.1073/pnas.2412456121 (2024)

Ca’ Foscari University of Venice has earned a spot among the top 250 universities worldwide in the inaugural edition of the Interdisciplinary Science Rankings (ISR) by Times Higher Education. This new ranking highlights the university’s excellence in fostering interdisciplinary research across Life Sciences, Physical Sciences and Engineering. The ISR evaluates over 700 universities from 92 countries, focusing on their ability to address complex global challenges through the integration of diverse fields of knowledge. By emphasizing a complementary approach to combining scientific expertise, the rankings spotlight institutions making significant strides in interdisciplinary collaboration. Performance is assessed in three key areas: inputs, which consider funding capabilities; process, encompassing facilities, administrative support, and promotion efforts; and outputs, focusing on publication quality, research impact, and institutional reputation. Ca’ Foscari stands out particularly in the outputs category, achieving a score of 48 points for its high-quality interdisciplinary publications and strong academic reputation. The university also demonstrates notable success in attracting research funding (37.1 points) and providing robust support structures for researchers (33.3 points). These achievements are largely attributed to the work of its two scientific departments: the Department of Environmental Sciences, Informatics and Statistics, and the Department of Molecular Sciences and Nanosystems. The ranking methodology combines data provided directly by universities with bibliometric data from Elsevier, offering a comprehensive picture of how institutions perform in interdisciplinary science. For more information, visit the official Times Higher Education Interdisciplinary Science Rankings.

Today, the Department of Molecular Sciences and Nanosystems at Ca’ Foscari University of Venice hosted an insightful talk by Dr Federico Levi, deputy editor at Nature, as part of the Engineering Physics Colloquia. The room was filled to capacity with 90 attendees, and additional participants joined via Zoom, underscoring the significant interest in the topics covered. During his presentation, Levi shed light on several critical aspects of the publishing process at Nature, including their stance on preprint submissions, the role of double-blind peer reviews, the pre-submission enquiry process, and many other topics. One highlight of the discussion was Nature‘s encouragement of preprint submissions to platforms like arXiv, a crucial tool for disseminating early-stage research and receiving feedback. The talk offered a rare glimpse into the journal’s editorial decision-making process, as Levi explained how Nature seeks to publish the most impactful scientific developments while ensuring that they resonate not only with specialized research communities but also with the broader public. His presentation emphasized how influential the journal can be in steering research by focusing on key scientific challenges, reflecting on the kinds of groundbreaking work that get selected for publication. Overall, the event was a great success and provided attendees with valuable insights into the editorial principles that guide Nature. It also opened discussions on the role of high-impact journals in shaping the global research agenda.

Topology, a fascinating branch of mathematics, explores the properties of figures or objects that remain unchanged under continuous deformations—those that do not involve cutting or sewing the object. Consider the everyday example of shoelaces: tying a knot involves passing one end under the other to create a more secure structure. If the ends were glued together, the knot would stay locked within the lace, and the only way to untie it would be to cut it. This concept of topology is crucial not only for understanding abstract mathematical objects, like the very definition of a “knot,” but it also has significant applications in various fields. These range from theoretical physics (including field theories and Feynman path integrals) to the statistical mechanics of soft matter (like polymers, liquid crystals, and other complex fluids), and even to essential biological molecules such as DNA, RNA, and proteins. Due to the vast and specialized nature of these fields, a common language to integrate their shared traits would be highly beneficial. The review titled “Topology in Soft and Biological Matter,” recently published in Physics Reports, seeks to achieve this integration. Starting from the rigorous language of knot theory and field theories in physics to the latest computational techniques and algorithms for quantifying the topological properties of real molecules, the review presents an extensive overview of the current applications of topological concepts in mathematics, physics, chemistry, and biology. This comprehensive review marks the culmination of a four-year journey under the COST Action CA17139 EUTOPIA, coordinated internationally by Prof. Luca Tubiana of the University of Trento. Funded by the European COST program, this initiative brought together scientists from almost all European Union countries and several partners, including Turkey, Israel, and the USA. Achille Giacometti, from the Ca’ Foscari University of Venice, coordinated the EUTOPIA working group “Polymeric and Fibrous Topological Materials,” overseeing the detailed sections on polymers and viscoelasticity. The European Centre for Living Technology (ECLT), directed by Achille Giacometti, hosted the working group that completed the final draft of the review. This review represents a significant collaborative effort, with 59 scientists from various institutions across Europe and its partners contributing to this ambitious project. Through their intense cooperative efforts, the review not only highlights the state of the art but also aims to establish a unified language for topological research across diverse scientific disciplines. The study was published in the Physics Reports journal. Full link: https://doi.org/10.1016/j.physrep.2024.04.002