Photoinduced Enhancement of Chemical Shift Sensitivity to Local Vibrations

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The photochemistry of UV-irradiated liquid water underlies many physical, chemical, and biological processes, with the formation of the hydrated electron as a central event. Despite extensive experimental and theoretical efforts, its microscopic origin remains incompletely understood. Using excited state molecular dynamics simulations of photoexcited liquid water, we resolve the sequence of chemical events leading to hydrated electron formation on the excited state. The excitation localizes on specific hydr

Plasma state reconstruction methods combining measurements and physics modeling improve the estimation of physics quantities in real-time and in post-discharge analysis. We present a workflow to reconstruct the dynamic evolution of a set of internal tokamak plasma profiles with consistent equilibria, as applied in this paper for experimental data from TCV L and H-mode discharges. Plasma profile estimates for electron temperature Te, electron density ne and parallel current density jpar are obtained by data

and contact resistances as low as 1.31 kΩ·μm at 1.5 K. These characteristics enable a gate-tunable metal-insulator transition at carrier densities down to 2.75 × 10¹⁰ cm⁻². Transport in this regime is dominated by electron-electron interactions, as supported by finite-temperature scaling. Below 50 K, however, an additional disorder-related energy scale emerges, consistent with percolation. These results demonstrate that disorder remains relevant even in high-mobility devices, challenging a purely interactio

Iron and nitrogen co‐doped FeNC catalysts with symmetric Fe‐N 4 as the active site are the most promising alternative to noble metal catalysts for proton exchange membrane fuel cells (PEMFCs). However, the symmetric structure in the Fe–N 4 site endows oxygen intermediates with strong binding energy, which hinders the activity optimization of the active center. In this work, an asymmetric configuration (Fe‐N 3 SC) is constructed to alleviate the electron localization caused by the d – π conjugation of Fe‐N 4

The present study investigated the role of alloy microstructure and surface roughness on wear and friction behavior of leaded and unleaded tin bronzes. Ball-on-disk experiments were carried out under dry conditions with steel balls sliding against bronze disks. Scanning electron microscopy (SEM), energy dispersive electron microscopy (EDX), x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy were performed to analyze the sliding tracks and the ball scars. The wear reducing effect of lead

Electronic properties of low-dimensional systems — and particularly quasi-one-dimensional systems — together with related correlated electron phenomena have for quite some time been at the very frontier of condensed matter physics. The interest ranges from purely fundamental reasons, since the reduced dimension offers a unique possibility of direct calculation of many-body problems, to nowadays very intense interest in functional nano-systems. Angle-resolved photoemission spectroscopy (ARPES) is arguably th

Plasma created during EDM is systematically investigated with optical emission spectroscopy. Typical spectra show a strong H,,, and continuum radiation, with many lines emitted by impurities coming from electrode and workpiece materials. The dielectric molecules are cracked by the discharge. Time-resolved spectroscopy shows that the electron density is extreme at the beginning of the discharge. This causes merging of lines, strong Stark broadening and shift of the H,, line. The electron temperature is low a

In this paper we present our latest developments in high precision positioning and handling systems operating inside an SEM. The Laboratory in Scanning Electron Microscope concept (LAB-in-SEM) is proposed along with a description of our piezodriven manipulators. Nano-material testing such as in-situ indentation and scratch have been conduct with our systems and are briefly related here. Finally, the preliminary tests of the tele-operated assembly of carbon nanotubes on AFM tips are described.These results w

Gold nanoparticles of 2–5 nm supported on woven fabrics of activated carbon fibers (ACF) were effective during CO oxidation at room temperature. To obtain a high metal dispersion, Au was deposited on ACF from aqueous solution of ethylenediamine complex [Au(en)2]Cl3 via ion exchange with protons of surface functional groups. The temperature-programmed decomposition method showed the presence of two main types of functional groups on the ACF surface: the first type was associated with carboxylic groups easily

Light Induced Chemical Vapour Deposition (LICVD) of titanium dioxide thin films is studied in this work. It is shown that this technique enables to deposit locally and selectively a chosen crystalline phase with a precise controlled thickness at low substrate temperature, allowing even the use of polymer substrates. A home made LICVD reactor was set up, consisting of a main chamber in which the substrate was placed on a temperature controlled plate and could be irradiated perpendicularly through a window by

The device has a semiconductor layer provided on an insulating layer and including source and drain (18,20) regions to define a body (22) region of respective field effect transistors. An energy band modifying unit modifies the valence and conduction band of the body region to increase the amount of electrical charge that can be temporarily stored in the region. An Independent claim is also included for a method of controlling a semiconductor device.

The Hohenberg-Kohn theorem states that the ground state electron density completely determines the external potential acting on an electron system. Inspired by this fundamental theorem, we developed a novel approach to map directly the electron potential in surface systems: linear response theory applied to the total electron density as measured with scanning tunneling microscopy determines the external potential. Potential imaging is demonstrated for the s-p derived surface state on Au(111), where the "her

This thesis is devoted to the study of screening and polarisation effects in a quantum plasma of electrons and protons, when the system is close to a dilute gas of hydrogen atoms. This atomic phase is obtained by considering a coupled low-density and low-temperature limit, in which the binding of charges into hydrogen atoms is favored. We study the electrical susceptibility of this plasma using a fugacity expansion of this function obtained from a resummed Mayer diagrammatic series. This expansion -- which

We discuss a novel approach to measure the electron phase-relaxation length and femtosecond lifetimes at surfaces. It relies on the study of the spatial decay of quantum interference patterns in the local density of states (LDOS) with the STM. The method has been applied to s-p derived surface-state electrons on Cu(111) and Ag(111). The characteristic decay length of the LDOS oscillations is influenced by the finite lifetime, and thus reveals information about inelastic scattering in the two-dimensional (2D

Spectromicroscopy with the imaging technique of X-ray photoelectron emission microscopy (X-PEEM) is a microchemical analytical tool installed in many synchrotron radiation laboratories, and which is finding application in diverse fields of research. The method of sample analysis, X-ray absorption spectroscopy, does not encounter the same problems as X-ray photoemission spectroscopy when sample charging occurs, hence even good insulators may often be analyzed without any apparent artifacts in images or spect

The attempt to prep. hitherto unknown homopolyat. cations of sulfur by the reaction of elemental sulfur with blue S8(AsF6)2 in liq. SO2/SO2ClF, led to red (in transmitted light) crystals identified crystallog. as S8(AsF6)2. The X-ray structure of this salt was redetd. with improved resoln. and cor. for librational motion: monoclinic, space group P21/c (No. 14), Z = 8, a = 14.986(2) .ANG., b = 13.396(2) .ANG., c = 16.351(2) .ANG., b = 108.12(1) Deg. The gas phase structures of E82+ and neutral E8 (E = S, Se)

We explored the degradation in electron beam pumped Zn1-xCdxSe/ZnSe laser structures by combining cathodoluminescence measurements in a scanning electron microscope with transmission electron microscopy. We found that degradation occurred via the formation of dark spot and dark line defects, and that it involved the formation of a characteristic type of defect, namely dislocation loops within the ZnCdSe quantum well, which grew to form a characteristic network as degradation progressed.

The parallel velocity distribution function of the weakly relativistic electron beam of a quasi-optical gyrotron has been determined by measuring the Doppler-shifted Electron Cyclotron Emission (ECE) at an angle theta=15 degrees with respect to the external magnetic de-field. Due to the Doppler shift, the frequency of the spontaneous cyclotron emission at the fundamental (nu(0) = 100 GHz) is upshifted to 140 GHz. A broadening of the spectrum up to 10 GHz [full width at half maximium (FWHM)] was measured. Th

Lead zirconium titanium oxide (PZT) thin films are used for their ferroelectric and piezoelectric properties. The composition of the PZT is very important for these properties, and may also be influenced by inter- diffusion with the bottom electrode, on which the PZT film has been grown at rather elevated temperature (550°C-600°C). The bottom electrode is essentially made of RuO2 deposited on a chromium adhesion layer which also helps to block oxygen diffusion. A part of the multi-layer device is shown in F

Radiative transfer is often the dominant energy transport channel in inertial confinement fusion experiments. It is a basic process needed in order to understand the behaviour of astrophysical plasmas, like stellar atmospheres and the inner parts of stars. Opacities account for photon absorption in matter. During decades, opacities have been numerically calculated on the basis of different atomic models. Before the nineties, no direct measurement of opacities spectra has been performed. The first experiment

Photoinduced Enhancement of Chemical Shift Sensitivity to Local Vibrations

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Simulating the Photochemical Birth of the Hydrated Electron in Liquid Water

Model-based Estimation of Tokamak Plasma Profiles and Physics Parameters: Integration with Improved Equilibrium Reconstruction and Experimental Data

Metal-insulator transition at low densities in a two-dimensional low-bandgap semiconductor

Rational Design of Asymmetric FeN3S Single‐Atom Sites for eg Orbital Engineering Toward Efficient ORR in PEMFCs

Wear and frictional mechanisms of copper-based bearing alloys

Angle-resolved photoemission spectroscopic properties of quasi-one-dimensional crystals

Optical emission spectroscopy of electrical discharge machining plasma

High Precision Robotics System for Scanning Electron Microscopes

Highly dispersed gold on activated carbon fibers for low temperature CO oxidation

Selective light induced chemical vapour deposition of titanium dioxide thin films

Method of forming an electric charge in a body of a semiconductor component

Imaging of electron potential landscapes on Au(111)

Etude des phénomènes d'écran et de polarisation dans un plasma quantique par la méthode des graphes de Mayer

Quantum coherence and lifetimes of surface-state electrons

Charging phenomena in PEEM imaging and spectroscopy

Bonding, Structure, and Energetics of Gaseous E82+ and of Solid E8(AsF6)2 (E = S, Se)

Degradation of electron-beam-pumped Zn1-xCdxSe/ZnSe GRINSCH blue-green lasers

Measurement of the parallel velocity distribution function of the electron beam in a quasi-optical gyrotron by Electron Cyclotron Emission

Chemical analysis of lead zirconium titanium oxide films

Calcul des opacités de plasmas denses. Eclatement du spectre dû aux interactions électroniques dans le cas du fer