Publications related to Heisenberg picture

Variational quantum time evolution without the quantum geometric tensor

Giuseppe Carleo, Riccardo Rossi, Julien Sebastian Gacon, Jannes Willy E. Nys, Stefan Woerner

Realand imaginary -time quantum state evolutions are crucial in physics and chemistry for exploring quantum dynamics, preparing ground states, and computing thermodynamic observables. On near -term devices, variational quantum time evolution is a promising ...

Amer Physical Soc2024

Spin wave spectra of single crystal CoPS3

Henrik Moodysson Rønnow, Luc Testa, Ursula Bengaard Hansen, Mechthild Enderle

The spin waves in single crystals of the layered van der Waals antiferromagnet CoPS3 have been measured using inelastic neutron scattering. The data show four distinct spin wave branches with large (>14 meV) energy gaps at the Brillouin zone center indicat ...

2023

Serial dependence in visual perception: A review

David Pascucci, Ayberk Ozkirli, Gizay Ceylan

How does the visual system represent continuity in the constantly changing visual input? A recent proposal is that vision is serially dependent: Stimuli seen a moment ago influence what we perceive in the present. In line with this, recent frameworks sugge ...

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

Magnetic exchange parameters and anisotropy of the quasi-two-dimensional antiferromagnet NiPS3

Diane Virginie Marie Lançon

Neutron inelastic scattering has been used to measure the magnetic excitations in powdered NiPS3, a quasitwo-dimensional antiferromagnet with spin S = 1 on a honeycomb lattice. The spectra show clear, dispersive magnons with a similar to 7 meV gap at the B ...

AMER PHYSICAL SOC2018

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

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

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

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

Magnetic structure and magnon dynamics of the quasi-two-dimensional antiferromagnet FePS3

Henrik Moodysson Rønnow, Diane Virginie Marie Lançon

Neutron scattering from single crystals has been used to determine the magnetic structure and magnon dynamics of FePS3, an S = 2 Ising-like quasi-two-dimensional antiferromagnet with a honeycomb lattice. The magnetic structure has been confirmed to have a ...

Amer Physical Soc2016

From Compact Semi-Toric Systems To Hamiltonian S-1-Spaces

Silvia Sabatini

We show how any labeled convex polygon associated to a compact semi-toric system, as de fined by V (u) over tilde Ngoc, determines Karshon's labeled directed graph which classifies the underlying Hamiltonian S-1-space up to isomorphism. Then we characteriz ...

Amer Inst Mathematical Sciences2015

Impact of saturation on the polariton renormalization in III-nitride based planar microcavities

Nicolas Grandjean, Jean-François Carlin, Raphaël Butté, Jacques Levrat, Eric Feltin, Georg Rossbach

It has been widely observed that an increasing carrier density in a strongly coupled semiconductor microcavity (MC) alters the dispersion of cavity polaritons, below and above the condensation threshold. The interacting nature of cavity polaritons stems fr ...

Amer Physical Soc2013

Emergence and Detection of Exotic Phases in Spin-1 Systems

Frédéric Alexis Michaud

This work is devoted to the study of spin S = 1 systems, and more precisely to the emergence of exotic quantum phases in such systems, and to the establishment of tools to observe such phases. It is split in four main chapters. In the first chapter, we sho ...

EPFL2013

Efficient DFT+U calculations of ballistic electron transport: Application to Au monatomic chains with a CO impurity

Gabriele Sclauzero

An efficient method for computing the Landauer-Buttiker conductance of an open quantum system within DFT + U is presented. The Hubbard potential is included in electronic-structure and transport calculations as a simple renormalization of the nonlocal pseu ...

Amer Physical Soc2013

Multipartite polariton entanglement in semiconductor microcavities

Vincenzo Savona, Timothy Chi Hin Liew

We study the entanglement of multiple polariton modes, which results in continuous variable cluster states suitable for quantum computation. Schemes are based on parametric scattering between spin-polarized lower and upper polariton branches in planar micr ...

2011

Accelerating Calculations of Ultrafast Time-Resolved Electronic Spectra with Efficient Quantum Dynamics Methods

Jiri Vanicek, Miroslav Sulc, Marius Wehrle

We explore three specific approaches for speeding up the calculation of quantum time correlation functions needed for time-resolved electronic spectra. The first relies on finding a minimum set of sufficiently accurate electronic surfaces. The second incre ...

2011

Neutron Scattering Investigations of Weakly Coupled and Weakly Connected Antiferromagnets

Krunoslav Prsa

Antiferromagnetic insulators at low temperatures offer a clean arena to study non-semiclassical phenomena because the character of interactions is usually known. Macroscopic properties of the system can then be calculated by more or less sophisticated appr ...

EPFL2010

Sintering of NaCl powder: Mechanisms and first stage kinetics

Andreas Mortensen, Jean-François Despois

Isothermal NaCl sintering experiments are conducted between 500 and 790 degrees C on powders 75, 100, 150 and 400 mu m in average diameter. Along with literature data, the results are compared with theoretical predictions for the initial stage of sintering ...

2006