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Concept

Longueur de Debye

Publications associées (28)

Effect of a temperature gradient on the screening properties of ionic fluids

Andrea Grisafi, Federico Grasselli

The electrostatic screening properties of ionic fluids are of paramount importance in countless physical processes. Yet the screening behavior of ionic conductors out of thermal equilibrium has to date mainly been studied in the context of thermoelectric p ...

AMER PHYSICAL SOC2023

Many-body screening effects in liquid water

Alfredo Pasquarello, Igor Reshetnyak, Arnaud Guillaume Lorin

The screening arising from many-body excitations is a crucial quantity for describing absorption and inelastic X-ray scattering (IXS) of materials. Similarly, the electron screening plays a critical role in state-of-the-art approaches for determining the f ...

Nature Portfolio2023

Range-separated hybrid functionals for accurate prediction of band gaps of extended systems

Alfredo Pasquarello, Stefano Falletta, Jing Yang

In this work, we systematically evaluate the accuracy in band gap prediction of range-separated hybrid functionals on a large set of semiconducting and insulating materials and carry out comparisons with the performance of their global counterparts. We obs ...

NATURE PORTFOLIO2023

Evolution of the electrical double layer with electrolyte concentration probed by second harmonic scattering

Sylvie Roke, Arianna Marchioro, Marie Bischoff, Bingxin Chu

Investigating the electrical double layer (EDL) structure has been a long-standing challenge and has seen the emergence of several sophisticated techniques able to probe selectively the few molecular layers of a solid/water interface. While a qualitative e ...

ROYAL SOC CHEMISTRY2023

Surface Charge Boundary Condition Often Misused in CO2 Reduction Models

Sophia Haussener, Etienne Boutin, Evan Fair Johnson

The Poisson-Nernst-Planck equations have been used to model species transport in electrochemical CO2 reduction, where the surface charge boundary condition accounts for the potential drop across the Stern layer. A direct comparison of the published models ...

AMER CHEMICAL SOC2023

Sheath collapse at critical shallow angle due to kinetic effects

Alessandro Geraldini

The Debye sheath is known to vanish completely in magnetised plasmas for a sufficiently small electron gyroradius and small angle between the magnetic field and the wall. This angle depends on the current onto the wall. When the Debye sheath vanishes, ther ...

IOP Publishing Ltd2022

Label-Free C-Reactive Protein Si Nanowire FET Sensor Arrays With Super-Nernstian Back-Gate Operation

Mihai Adrian Ionescu, Luca Capua, Yann Christophe Sprunger, Felix Risch

We present a CMOS-compatible double gate and label-free C-reactive protein (CRP) sensor, based on silicon on insulator (SOI) silicon nanowires arrays. We exploit a reference subtracted detection method and a super-Nernstian internal amplification given by ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

In situ nanoscale studies of copper-based catalysts for carbon dioxide electroreduction

Karla Banjac

The urgency of climate change demands the simultaneous removal of carbon dioxide from the atmosphere and the transition to renewable energy sources. This aim is realizable through electrochemical reduction of carbon dioxide (CO2RR), which is a promising ro ...

EPFL2021

How to polarise an interface with ions: the discrete Helmholtz model

Hubert Girault, Astrid Johana Olaya Avendano, Grégoire Clément Gschwend

The distribution of electrolytes in an electric field usually relies on theories based on the Poisson-Boltzmann formalism. These models predict that, in the case of a metallic electrode, ionic charges screen the electrode potential, leading to concentratio ...

2020

Mapping Electrochemical Heterogeneity at Gold Surfaces: A Second Harmonic Imaging Study

Sylvie Roke, Arianna Marchioro, Igor Nahálka

Designing efficient catalysts requires correlating surface structure and local chemical composition with reactivity on length scales from nanometers to tens of microns. While much work has been done on this structure/function correlation on single crystals ...

2020

Continuum models of the electrochemical diffuse layer in electronic-structure calculations

Nicola Marzari, Oliviero Andreussi, Francesco Nattino

Continuum electrolyte models represent a practical tool to account for the presence of the diffuse layer at electrochemical interfaces. However, despite the increasing popularity of these in the field of materials science, it remains unclear which features ...

AMER INST PHYSICS2019

Colloidal Size and Redox State of Uranium Species in the Porewater of a Pristine Mountain Wetland

Rizlan Bernier-Latmani, Barbora Bártová, Manon Frutschi, Ashley Richards Brown, Gabrielle Dublet, Giada Chantal Zünd

Uranium (U) speciation was investigated in anoxically preserved porewater samples of a natural mountain wetland in Gola di Lago, Ticino, Switzerland. U porewater concentrations ranged from less than 1 mu g/L to tens of mu g/L, challenging the available ana ...

AMER CHEMICAL SOC2019

Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering

Yixing Chen, Sylvie Roke, Halil Ibrahim Okur, Nathan Dupertuis

The temperature dependence of the femtosecond elastic second harmonic scattering (fs-ESHS) response of bulk light and heavy water and their electrolyte solutions is presented. We observe clear temperature dependent changes in the hydrogen (H)-bond network ...

2018

Influence of the thickness of a nanometric copper interlayer on Au/dielectric thermal boundary conductance

Ludger Weber, Maïté Blank

The influence of the thickness of a thin (1.5-30 nm) copper layer on the thermal boundary conductance (TBC) at the interface between gold and silicon, sapphire and diamond, respectively, was studied using Time Domain Thermoreflectance. Overall, a monotonic ...

2018

Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system

Olivier Sauter, Martinus Adela Maria Gijs, Jonathan Graves, Ambrogio Fasoli, Stefano Coda, Basil Duval, Henri Weisen, Richard Pitts, Yves Martin, Javier García Hernández, Duccio Testa, Miguel Fernández Ruiz, Nicola Vianello, Robin Humphry-Baker, Sun Hee Kim, Federico Nespoli, Patrick Blanchard, Alessandro Pau, David Pfefferlé, Davide Galassi, Jonathan Marc Philippe Faustin, Cristian Sommariva, Hamish William Patten, Samuel Lanthaler, Jan Horacek, Yann Camenen, Bruno Emanuel Ferreira De Sousa Correia, José Pedro Rebelo Ferreira Marques, Mikhail Maslov, Marco Wischmeier, Dalziel Joseph Wilson, Liang Yao, Daniel Scott Alessi, Arnout Lodewijk M Beckers, Ana Francisca Leal Silva Soares, Jonnathan Cesar Hidalgo Acosta, Antonio José Pereira de Figueiredo, Partha Dutta, Pierre-Thomas Paul Brun, Pedro Camilo de Oliveira e Silva, Alberto Hernando de Castro, Julio Rodriguez, Vlad Trifa, Li Shuai, Rebecca Hill

Diagnostic alkali atom (e.g., lithium) beams are routinely used to diagnose magnetically confined plasmas, namely, to measure the plasma electron density profile in the edge and the scrape off layer region. A light splitting optics system was installed int ...

2018

Communication: Mean-field theory of water-water correlations in electrolyte solutions

Michele Ceriotti, Sylvie Roke, David Mark Wilkins

Long-range ion induced water-water correlations were recently observed in femtosecond elastic second harmonic scattering experiments of electrolyte solutions. To further the qualitative understanding of these correlations, we derive an analytical expressio ...

American Institute of Physics2017

The Molecular Mechanism of Nanodroplet Stability

Yixing Chen, Sylvie Roke, Halil Ibrahim Okur, David Mark Wilkins, Evangelia Zdrali

Mixtures of nano- and microscopic oil droplets in water have recently been rediscovered as miniature reaction vessels in microfluidic environments and are important constituents of many environmental systems, food, personal care, and medical products. The ...

Amer Chemical Soc2017

Evidence for Marginal Stability in Emulsions

Matthieu Wyart

We report the first measurements of the effect of pressure on vibrational modes in emulsions, which serve as a model for soft frictionless spheres at zero temperature. As a function of the applied pressure, we find that the density of states D(omega) exhib ...

American Physical Society2016

A gauge invariant Debye mass and the complex heavy-quark potential

Yannis Burnier

Following the original idea of Debye, we define and extract a gauge-invariant screening mass from the complex static in-medium heavy-quark potential V-Q (Q) over bar, recently obtained from lattice QCD. To this end we derive a formula using concepts from b ...

Elsevier2016

A generalized Poisson and Poisson-Boltzmann solver for electrostatic environments

Nicola Marzari, Oliviero Andreussi

The computational study of chemical reactions in complex, wet environments is critical for applications in many fields. It is often essential to study chemical reactions in the presence of applied electrochemical potentials, taking into account the non-tri ...

Amer Inst Physics2016

Publications associées (28)

Temperature dependence of water-water and ion-water correlations in bulk water and electrolyte solutions probed by femtosecond elastic second harmonic scattering

Yixing Chen, Sylvie Roke, Halil Ibrahim Okur, Nathan Dupertuis

2018

Influence of the thickness of a nanometric copper interlayer on Au/dielectric thermal boundary conductance

Ludger Weber, Maïté Blank

2018

Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system

2018