Publications associées à Représentation de Schrödinger

High-order geometric integrators for the variational Gaussian wavepacket dynamics and application to vibronic spectra at finite temperature

Molecular quantum dynamics simulations are essential for understanding many fundamental phenomena in physics and chemistry. They often require solving the time-dependent Schrödinger equation for molecular nuclei, which is challenging even for medium-sized ...

EPFL2024

Large-cage occupation and quantum dynamics of hydrogen molecules in sII clathrate hydrates

Richard Gaal, Livia Eleonora Bove Kado, Umbertoluca Ranieri

Hydrogen clathrate hydrates are ice-like crystalline substances in which hydrogen molecules are trapped inside polyhedral cages formed by the water molecules. Small cages can host only a single H-2 molecule, while each large cage can be occupied by up to f ...

Aip Publishing2024

High-order geometric integrators for the variational Gaussian approximation

Jiri Vanicek, Roya Moghaddasi Fereidani

Among the single-trajectory Gaussian-based methods for solving the time-dependent Schrödinger equation, the variational Gaussian approximation is the most accurate one. In contrast to Heller’s original thawed Gaussian approximation, it is symplectic, conse ...

2023

A time-reversible integrator for the time-dependent Schrödinger equation on an adaptive grid

Jiri Vanicek, Seonghoon Choi

One of the most accurate methods for solving the time-dependent Schrödinger equation uses a combination of the dynamic Fourier method with the split-operator algorithm on a tensor-product grid. To reduce the number of required grid points, we let the grid ...

2019

The S-matrix bootstrap IV: multiple amplitudes

João Miguel Augusto Penedones Fernandes, Jonathan Campbell Toledo

We explore the space of consistent three-particle couplings in Z(2)-symmetric two-dimensional QFTs using two first-principles approaches. Our first approach relies solely on unitarity, analyticity and crossing symmetry of the two-to-two scattering amplitud ...

Springer Nature2019

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

Nonadiabatic effects in electronic and nuclear dynamics

Majed Chergui, Ursula Röthlisberger, Jiri Vanicek, Martin Peter Bircher, Tomas Zimmermann, Elisa Liberatore, Aurélien Kevin Fabrice Patoz, Nicholas John Browning

Due to their very nature, ultrafast phenomena are often accompanied by the occurrence of nonadiabatic effects. From a theoretical perspective, the treatment of nonadiabatic processes makes it necessary to go beyond the (quasi) static picture provided by th ...

2017

Geometric Integrators for Nonadiabatic Molecular Quantum Dynamics Induced by the Interaction with the Electromagnetic Field

Aurélien Kevin Fabrice Patoz

Understanding the elementary steps involved in a chemical reaction forms the cornerstone of physical chemistry research. One way to deepen this understanding is by studying chemical and physical processes using linear and nonlinear spectroscopic techniques ...

EPFL2017

Exact diagonalization of SU( N ) Heisenberg and Affleck-Kennedy-Lieb-Tasaki chains using the full SU( N ) symmetry

Frédéric Mila, Pierre Marcel Nataf, Kianna Wan

We present a method for the exact diagonalization of the SU(N) Heisenberg interaction Hamiltonian using Young tableaus to work directly in each irreducible representation of the global SU(N) group. This generalized scheme is applicable to chains consisting ...

2017

In vivo neurochemical measurements in cerebral tissues using a droplet-based monitoring system

Philippe Renaud, Guillaume Cédric Yves Petitpierre, Bernard Schneider, Arnaud Bertsch, Philippe Colin, Aurélien Thomas

Direct collection of extracellular fluid (ECF) plays a central role in the monitoring of neurological disorders. Current approaches using microdialysis catheters are however drastically limited in term of temporal resolution. Here we show a functional in v ...

Nature Publishing Group2017