Publications associées à Théorème adiabatique

Gyrokinetic simulation of short wavelength ion temperature gradient instabilities in the ADITYA-U tokamak

In this work, linear and nonlinear collisionless electrostatic simulation studies of the standard and short wavelength ion temperature gradient mode (SWITG) for experimental profiles and parameters of ADITYA-U tokamak are performed using the linear global ...

IOP Publishing Ltd2023

Phonon Self-Energy Corrections: To Screen, or Not to Screen

Nicola Marzari, Samuel Poncé

First-principles calculations of phonons are often based on the adiabatic approximation and on Brillouinzone samplings that might not always be sufficient to capture the subtleties of Kohn anomalies. These shortcomings can be addressed through corrections ...

American Physical Society2023

Spin Evolution in the Born-Oppenheimer Approximation

Jean-Philippe Ansermet, François Reuse, Klaus Maschke

The first part of this article attempts to highlight in chronological order some prominent papers that have direct connexion with the Born-Oppenheimer approximation. This timeline successively points to the role of level crossing, the notions of gauge fiel ...

WILEY-V C H VERLAG GMBH2022

Effect of collisions on non-adiabatic electron dynamics in ITG-driven microturbulence

Stephan Brunner, Justin Richard Ball

Non-adiabatic electron response leads to significant changes in ion temperature gradient (ITG) eigenmodes, leading, in particular, to fine-structures that are significantly extended along the magnetic field lines at corresponding mode rational surfaces (MR ...

2021

Simultaneous Perturbation Stochastic Approximation of the Quantum Fisher Information

Giuseppe Carleo, Julien Sebastian Gacon, Stefan Woerner

The Quantum Fisher Information matrix (QFIM) is a central metric in promising algorithms, such as Quantum Natural Gradient Descent and Variational Quantum Imaginary Time Evolution. Computing the full QFIM for a model with d parameters, however, is computat ...

VEREIN FORDERUNG OPEN ACCESS PUBLIZIERENS QUANTENWISSENSCHAF2021

Which form of the molecular Hamiltonian is the most suitable for simulating the nonadiabatic quantum dynamics at a conical intersection?

Jiri Vanicek, Seonghoon Choi

Choosing an appropriate representation of the molecular Hamiltonian is one of the challenges faced by simulations of the nonadiabatic quantum dynamics around a conical intersection. The adiabatic, exact quasidiabatic, and strictly diabatic representations ...

2020

Nonlinear gyrokinetic PIC simulations in stellarators with the code EUTERPE

Laurent Villard, Eduardo Sanchez, Alberto Bottino

In this work, the first nonlinear particle-in-cell simulations carried out in a stellarator with the global gyrokinetic code EUTERPE using adiabatic electrons and realistic plasma parameters are reported. Several studies are conducted with the aim of enabl ...

Cambridge University Press2020

Linear collisionless dynamics of the GAM with kinetic electrons: Comparison simulations/theory

Alberto Bottino

Barely trapped and passing electrons have been recently predicted to strongly enhance the damping rate of Geodesic Acoustic Modes (GAMs) in tokamak plasmas, while keeping their real frequency almost unchanged as compared to the case with adiabatic electron ...

AMER INST PHYSICS2019

Silicon Photonic MEMS Phase-Shifter

Niels Quack, Hamed Sattari, Teodoro Graziosi, Marcell Kristof Kiss

We present a design for an analog phase shifter based on Silicon Photonic MEMS technology. The operation principle is based on a two-step parallel plate electrostatic actuation mechanism to bring a vertically movable suspended tapered waveguide in a first ...

2019

Improved off‐resonance phase behavior using a phase‐inverted adiabatic half‐passage pulse for 13 C MRS in humans at 7 T

Rolf Gruetter, Lijing Xin, Daniel Gallichan, Eulalia Serés Roig

In vivo (13) C MRS at high field benefits from an improved SNR and spectral resolution especially when using surface coils in combination with adiabatic pulses, such as the adiabatic half-passage (AHP) pulse for (13) C excitation. However, the excitation p ...

2019

Parameters affecting thermal risk through a kinetic model under adiabatic condition: Application to liquid-liquid reaction system

Thierry Meyer

Risk of thermal runaway for epoxidation is not negligible and should be analyzed and assessed. In industry, epoxidation of vegetable oils is carried out by the oxidation of Prileschajew, involving the in situ production of percarboxylic acid from hydrogen ...

2018

Geometric phases in discrete dynamical systems

Nicolas Piro Mastracchio

In order to study the behaviour of discrete dynamical systems under adiabatic cyclic variations of their parameters, we consider discrete versions of adiabatically-rotated rotators. Parallelling the studies in continuous systems, we generalize the concept ...

Elsevier Science Bv2016

Padé approximation of the adiabatic electron contribution to the gyrokinetic quasi-neutrality equation in the ORB5 code

Laurent Villard, Stephan Brunner, Emmanuel Lanti, Ben McMillan, Julien Stanislas Pierre Dominski

This work aims at completing the implementation of a solver for the quasineutrality equation using a PadÃ© approximation in the global gyrokinetic code ORB5. Initially [Dominski, Ph.D. thesis, 2016], the Pade approximation was only implemented for the kine ...

2016

Explicit solvent simulations of the aqueous oxidation potential and reorganization energy for neutral molecules: Gas phase, linear solvent response, and non-linear response contributions

Jeremy Samuel Arey, Peter Rudolf Tentscher, Marianne Seijo, Jennifer Guerard

First principles simulations were used to predict aqueous one-electron oxidation potentials (E-ox) and associated half-cell reorganization energies (lambda(aq)) for aniline, phenol, methoxybenzene, imidazole, and dimethylsulfide. We employed quantum mechan ...

Royal Soc Chemistry2015

Analysis of adiabatic trapping for quasi-integrable area-preserving maps

Cedric Jean-François Hernalsteens, Massimo Giovannozzi

Trapping phenomena involving nonlinear resonances have been considered in the past in the framework of adiabatic theory. Several results are known for continuous-time dynamical systems generated by Hamiltonian flows in which the combined effect of nonlinea ...

American Physical Society2014

The collisional depolarization of OH(A (2)Sigma(+)) and NO(A (2)Sigma(+)) with Kr

Quantum beat spectroscopy has been used to measure rate coefficients at 300 K for collisional depolarization for NO(A (2)Sigma(+)) and OH(A (2)Sigma(+)) with krypton. Elastic depolarization rate coefficients have also been determined for OH(A) + Kr, and sh ...

Amer Inst Physics2014

Planck 2013 results. XXII. Constraints on inflation

Julien Lesgourgues, Jean-Luc Starck, Fabio Finelli, Jan Hamann

We analyse the implications of the Planck data for cosmic inflation. The Planck nominal mission temperature anisotropy measurements, combined with the WMAP large-angle polarization, constrain the scalar spectral index to be n(s) = 0.9603 +/- 0:0073, ruling ...

EDP Sciences2014

Ab initio-driven trajectory-based nuclear quantum dynamics in phase space

Ivano Tavernelli

We derive a Bohmian trajectory-based quantum dynamics approach for the calculation of adiabatic and nonadiabatic quantum effects in ab initio on-the-fly molecular dynamics simulations. The method is designed for calculations in the full, unconstrained, pha ...

Amer Physical Soc2013

Adiabatic Passage of Light in CMOS-Compatible Silicon Oxide Integrated Rib Waveguides

Victor Javier Cadarso Busto

A fully complementary metal-oxide-semiconductor-compatible adiabatic passage of light in the visible range is presented in this letter. We experimentally show that a system of three total internal reflection waveguides, which has been defined by using non- ...

2012

Measuring nonadiabaticity of molecular quantum dynamics with quantum fidelity and with its efficient semiclassical approximation

Jiri Vanicek, Tomas Zimmermann

We propose to measure nonadiabaticity of molecular quantum dynamics rigorously with the quantum fidelity between the Born-Oppenheimer and fully nonadiabatic dynamics. It is shown that this measure of nonadiabaticity applies in situations where other criter ...

American Institute of Physics2012