Publications associées à Fonction de Wigner

Thermal conductivity of glasses: first-principles theory and applications

Predicting the thermal conductivity of glasses from first principles has hitherto been a very complex problem. The established Allen-Feldman and Green-Kubo approaches employ approximations with limited validity-the former neglects anharmonicity, the latter ...

NATURE PORTFOLIO2023

The Allen-Cahn equation with generic initial datum

Martin Hairer

We consider the Allen-Cahn equation ?(t)u - ?u = u - u(3) with a rapidly mixing Gaussian field as initial condition. We show that provided that the amplitude of the initial condition is not too large, the equation generates fronts described by nodal sets o ...

SPRINGER HEIDELBERG2023

Nonlinear inviscid damping and shear-buoyancy instability in the two-dimensional Boussinesq equations

Michele Dolce

We investigate the long-time properties of the two-dimensional inviscid Boussinesq equations near a stably stratified Couette flow, for an initial Gevrey perturbation of size & epsilon;. Under the classical Miles-Howard stability condition on the Richardso ...

WILEY2023

Stochastic particle transport by deep-water irregular breaking waves

Debbie Eeltink

Correct prediction of particle transport by surface waves is crucial in many practical applications such as search and rescue or salvage operations and pollution tracking and clean-up efforts. Recent results by Deike et al. (J. Fluid Mech., vol. 829, 2017, ...

Cambridge University Press2023

Wigner Formulation of Thermal Transport in Solids

Nicola Marzari, Michele Simoncelli

Two different heat-transport mechanisms are discussed in solids. In crystals, heat carriers propagate and scatter particlelike as described by Peierls's formulation of the Boltzmann transport equation for phonon wave packets. In glasses, instead, carriers ...

American Physical Society2022

High-Throughput Sizing, Counting, and Elemental Analysis of Anisotropic Multimetallic Nanoparticles with Single-Particle Inductively Coupled Plasma Mass Spectrometry

Andreas Züttel, Natalia Gasilova, Cedric David Koolen, Wen Luo, Mo Li, Ayush Agarwal

Nanoparticles (NPs) have wide applications in physical and chemical processes, and their individual properties (e.g., shape, size, and composition) and ensemble properties (e.g., distribution and homogeneity) can significantly affect the performance. Howev ...

2022

Wigner Measures and Coherent Quantum Control

Tudor Ratiu

We introduce Wigner measures for infinite-dimensional open quantum systems; important examples of such systems are encountered in quantum control theory. In addition, we propose an axiomatic definition of coherent quantum feedback. ...

2021

Search for CP violation in Xi(-)(b) -> pK(-)K(-) decays

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Elena Graverini, Veronica Sølund Kirsebom, François Fleuret, Ettore Zaffaroni, Matthieu Philippe Luther Marinangeli, Renato Quagliani, Federico Betti, Minh Tâm Tran, Donal Patrick Hill, Aravindhan Venkateswaran, Federico Leo Redi, Vitalii Lisovskyi, Violaine Bellée, Maria Vieites Diaz, Elisabeth Maria Niel, Pavol Stefko, Tara Nanut, Jian Wang, Maria Elena Stramaglia, Mingkui Wang, Vladimir Macko, Guillaume Max Pietrzyk, Zhirui Xu, Chao Wang, Sebastian Schulte, Lino Ferreira Lopes, Yi Zhang, Surapat Ek-In, Lei Zhang, Carina Trippl, Ho Ling Li, Sara Celani, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Dissociative Sticking Probability of Methane on Pt(110)-(2×1)

Rainer Beck, Ana Gutiérrez González

In this work, we revisit the dissociative sticking of methane on Pt(110)-(2×1) using quasi-classical trajectory (QCT) calculations and supersonic molecular beam (SMB) experiments. Experimentally, we apply the King and Wells method and the reflection absorp ...

2021

Ultimate control in chemistry

Andreas Osterwalder

Controlling reactions between molecules is a major fundamental goal in chemistry and doing so on the level of individual quantum states is very challenging. Now, control over the reactant state and full characterization of the product-state distribution of ...

2021

All-Dielectric Programmable Huygens' Metasurfaces

Hatice Altug, Andreas Tittl, Aleksandrs Leitis

Low-loss nanostructured dielectric metasurfaces have emerged as a breakthrough platform for ultrathin optics and cutting-edge photonic applications, including beam shaping, focusing, and holography. However, the static nature of their constituent materials ...

2020

SVR-AMA: An Asynchronous Alternating Minimization Algorithm With Variance Reduction for Model Predictive Control Applications

Colin Neil Jones, Ye Pu

This paper focuses on the design of an asynchronous dual solver suitable for model predictive control (MPC) applications. The proposed solver relies on a state-of-the-art variance reduction (VR) scheme, previously used in the context of proximal stochastic ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2019

Data-Driven Distributionally Robust Optimization Using the Wasserstein Metric: Performance Guarantees and Tractable Reformulations

Daniel Kuhn, Peyman Mohajerin Esfahani

We consider stochastic programs where the distribution of the uncertain parameters is only observable through a finite training dataset. Using the Wasserstein metric, we construct a ball in the space of (multivariate and non-discrete) probability distribut ...

2018

Vibrationally and Rotationally Inelastic Scattering of Methane from Ni(111)

Jörn Werdecker

This thesis presents a quantum-state-resolved molecular beam study of the non-reactive scattering of methane (CH4) from a Ni(111) surface. It is one of the first experimental investigations in which the internal quantum state distribution of a polyatomic m ...

EPFL2018

Higher order Larmor radius corrections to guiding-centre equations and application to fast ion equilibrium distributions

Jonathan Graves, Wilfred Anthony Cooper, David Pfefferlé, Samuel Lanthaler

An improved set of guiding-centre equations, expanded to one order higher in Larmor radius than usually written for guiding-centre codes, are derived for curvilinear flux coordinates and implemented into the orbit following code VENUS-LEVIS. Aside from gre ...

Iop Publishing Ltd2017

On sums of eigenvalues of elliptic operators on manifolds

Joachim Stubbe

We use the averaged variational principle introduced in a recent article on graph spectra [10] to obtain upper bounds for sums of eigenvalues of several partial differential operators of interest in geometric analysis, which are analogues of Kroger's bound ...

European Mathematical Soc2017

Differential chirped-pulse pair for sub-meter spatial resolution Brillouin distributed fiber sensing

Luc Thévenaz, Marcelo Alfonso Soto Hernandez, Zhisheng Yang

A distributed fiber sensor based on a differential chirped-pulse pair Brillouin optical time domain analysis (DCPBOTDA) is proposed for sub-meter spatial resolution sensing. The technique is based on the subtraction of two measurements made with the same p ...

SPIE2015

Initial or final values for semiclassical evolutions in the Weyl–Wigner representation

David Eduardo Zambrano Ramirez

Initial value representations are constructed to avoid the search for trajectories that are only defined in semiclassical approximations by their boundary conditions. We show how to incorporate these procedures within the full Weyl representation, so that ...

2013

Phase properties of operator valued measures in phase space

Vivishek Sudhir

The Wigner phase operator (WPO) is identified as an operator valued measure (OVM) and its eigenstates are obtained. An operator satisfying the canonical commutation relation with the Wigner phase operator is also constructed and this establishes a Wigner d ...

Taylor & Francis Ltd2013

Role of sampling in evaluating classical time autocorrelation functions

Jiri Vanicek, Tomas Zimmermann

We analyze how the choice of the sampling weight affects efficiency of the Monte Carlo evaluation of classical time autocorrelation functions. Assuming uncorrelated sampling or sampling with constant correlation length, we propose a sampling weight for whi ...

American Institute of Physics2013