Publications associées à Dynamics of photoexcited Ba+ cations in 4He nanodroplets

Scaling Description of Dynamical Heterogeneity and Avalanches of Relaxation in Glass-Forming Liquids

We provide a theoretical description of dynamical heterogeneities in glass-forming liquids, based on the premise that relaxation occurs via local rearrangements coupled by elasticity. In our framework, the growth of the dynamical correlation length e and o ...

American Physical Society2023

Long-Distance Coherent Propagation of High-Velocity Antiferromagnetic Spin Waves

Jean-Philippe Ansermet, Haiming Yu, Song Liu, Jilei Chen, Cheng Song, Rundong Yuan, Yao Zhang

We report on coherent propagation of antiferromagnetic (AFM) spin waves over a long distance (similar to 10 mu m) at room temperature in a canted AFM alpha-Fe2O3 owing to the Dzyaloshinskii-Moriya interaction (DMI). Unprecedented high group velocities (up ...

AMER PHYSICAL SOC2023

Modelling of metal alloys in realistic conditions with machine learning

Nataliya Lopanitsyna

Computer simulations based on statistical methods have emerged as a powerful tool for studying structure-property relationships at the atomistic level. However, to provide reliable insights into materials in realistic conditions, it is essential to accurat ...

EPFL2023

Anti-Jahn-Teller effect induced ultrafast insulator to metal transition in perovskite BaBiO3

Changpeng Lin, Ben Xu

The Jahn-Teller (JT) effect involves the ions M with a degenerate electronic state distorting the corner-sharing MO6 octahedra to lift the degeneracy, inducing strong coupling of electrons to lattice, and mediating the exotic properties in perovskite oxide ...

NATURE PORTFOLIO2022

Scrutinizing thermally stimulated current transients originating from trapped charges in organic semiconductors: A drift-diffusion study

Frank Nüesch, Beat Ruhstaller

Thermally stimulated current (TSC) is a widely used technique to assess trap states and extract their density, energy, and capture rate using analytical expressions. In many cases, the latter are derived from physical models pertaining to inorganic semicon ...

AIP Publishing2022

High-Temperature HEMT Mode

Farzan Jazaeri, Nika Sahebghalam

Taking into account the impact of self-heating and temperature rise effects, this work presents a physics-based analytical model for HEMTs, operating continuously from room temperature to high temperatures in linear and saturation regimes. Relying on the c ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Correction of Human Forehead Temperature Variations Measured by Non-Contact Infrared Thermometer

Adrian Shajkofci

Elevated body temperature (fever) can be a common symptom of a medical condition, such as a viral or bacterial infection, including SARS-CoV-2 or influenza. Non-contact infrared thermometers are able to measure forehead temperature in a timely manner and w ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Failure mechanism of fine-grained soil-structure interface for energy piles

Lyesse Laloui, Elena Ravera

The response of the soil-structure interface can significantly affect the performance of any geotechnical structure. Thermal cycles are a new factor that influence the response to all structures that have an energy function in addition to the structural on ...

2022

Fractal Modeling of Polymer Plasma Laser Ablation, Plasma Plume Tsallis Entropy and Its q-Statistics Interpretation, Part I: Theory

Maria-Alexandra Paun

Polymer plasma produced by laser ablation is investigated in a theoretical manner. In relation to the fact that the charge carrier circulation is assumed to take place on fractal curves, the so-called fractality type, electrical charge transport can be res ...

MDPI2022

Modelling electronic transport in monocrystalline metal oxide gas sensors: from the surface kinetics to the experimental response

Roberto Guarino, Gianluca Piccinini

Gas sensing systems and devices based on metal oxides are widely spreading due to their high performance in terms of sensor response and relatively low costs. Despite several experimental studies, as well as molecular simulations, are available in the lite ...

2022

Cryogenic MOSFET Modeling for Large-Scale Quantum Computing

Arnout Lodewijk M Beckers

Promising results of state-of-the-art quantum computers fuel a world-wide effort in academic and private research laboratories to scale up the number of qubits and improve their characteristics in large arrays. To meet the scale-up challenge, innovative mi ...

EPFL2021

Entropic Fokker-Planck kinetic model

Mohammadhossein Gorji

The diffusion limit of kinetic systems has been subject of numerous studies since prominent works of Lebowitz et al. [1] and van Kampen [2]. More recently, the topic has seen a fresh interest from the rarefied gas simulation perspective. In particular, Fok ...

2021

Luminescent lanthanide nanocomposites in thermometry: Chemistry of dopant ions and host matrices

Mohammad Khaja Nazeeruddin

Recently, there has been observed huge progress in the advancement of remote optical nanothermometry, as it plays a vital role in remote, noninvasive, and remote temperature sensing, which is especially important for various bio-applications, e.g., in ther ...

ELSEVIER SCIENCE SA2021

A universal signature in the melting of metallic nanoparticles

Kevin Rossi

Predicting when phase changes occur in nanoparticles is fundamental for designing the next generation of devices suitable for catalysis, biomedicine, optics, chemical sensing and electronic circuits. The estimate of the temperature at which metallic nanopa ...

ROYAL SOC CHEMISTRY2021

Low-energy stereodynamics of ion-forming reactions

Junwen Zou

In this thesis, an experimental study of low-temperature stereodynamics in the reactive scattering of Ne(3P2) + X collisions (X = Ar, Kr, Xe, CO and N2) is presented. The steric effect of Ne(3P2) in these reactions is observed experimentally using a contro ...

EPFL2021

Molecular Origin of the Asymmetric Photoluminescence Spectra of CsPbBr3 at Low Temperature

Michael Graetzel, Ursula Röthlisberger, Gwénolé Jean Jacopin, Mohammad Ibrahim Dar, Ariadni Boziki

CsPbBr3 has received wide attention due to its superior emission yield and better thermal stability compared to other organic-inorganic lead halide perovskites. In this study, through an interplay of theory and experiments, we investigate the molecular ori ...

2021

Photo- and thermally-induced electronic and structural dynamics in perovskites and transition metal oxides

Oliviero Cannelli

In this thesis, we exploited optical and X-ray pump-probe methods in a synergistic approach to study the interplay of the electronic, spin and structural degrees of freedom in two class of complex systems relevant for solar energy conversion applications: ...

EPFL2021

Optimization of composition and structure of cemented carbide cutting tools

Samy Adjam

WC-Co cemented carbides are composites, which combine a hard phase consisting of WC grains and a metallic ductile phase as a binder. Their excellent mechanical properties, combining high hardness, toughness and refractory properties, make them excellent ma ...

EPFL2021

Efficient Semiclassical Dynamics for Vibronic Spectroscopy beyond Harmonic, Condon, and Zero-Temperature Approximations

Jiri Vanicek, Tomislav Begusic

Understanding light-induced processes in biological and human-made molecular systems is one of the main goals of physical chemistry. It has been known for years that the photoinduced dynamics of atomic nuclei can be studied by looking at the vibrational su ...

2021

Atomic scale investigations of fracture in metal alloys

Eleanor Yi Kei Mak

The demand for metal alloys with superior structural performance in industrial applications continues to increase, as does the need for more-energy efficient materials and methods. Many materials that are otherwise attractive for structural applications ar ...

EPFL2021