Concept

Ab initio

Related publications (32)

High intensity x-ray interaction with a model bio-molecule system: double-core-hole states and fragmentation of formamide

Formamide, a simple model bio-molecule (HCONH2), is irradiated with high intensity, ultrashort pulses from an x-ray free electron laser. Ionic fragments resulting from photoionization and subsequent decay processes are recorded, as well as the electronic s ...

IOP Publishing2020

Strongly Coupled Coherent Phonons in Single-Layer MoS2

Andras Kis, Dumitru Dumcenco

We present a transient absorption setup combining broadband detection over the visible-UV range with high temporal resolution (similar to 20 fs) which is ideally suited to trigger and detect vibrational coherences in different classes of materials. We gene ...

AMER CHEMICAL SOC2020

Weyl fermions, Fermi arcs, and minority-spin carriers in ferromagnetic CoS2

Thorsten Schmitt, Samuel Thomas Stolz

Magnetic Weyl semimetals are a newly discovered class of topological materials that may serve as a platform for exotic phenomena, such as axion insulators or the quantum anomalous Hall effect. Here, we use angle-resolved photoelectron spectroscopy and ab i ...

2020

Electrons leave the flatland: out-of-plane charge dynamics in layered materials

Edoardo Martino

The goal of this thesis is to explore the "neglected" third dimension of layered materials, by studying the interlayer charge dynamics through dc conductivity, optical spectroscopy and ab-initio calculations. This project was designed to respond to the gro ...

EPFL2020

Gold Chain Formation via Local Lifting of Surface Reconstruction by Hot Electron Injection on H-2(D-2)/Au(111)

Klaus Kern, Anna Maria Roslawska, Abhishek Grewal

The hexagonal close packed surface of gold shows a 22 x root 3 "herringbone" surface reconstruction which makes it unique among the (111) surfaces of all metals. This long-range energetically favored dislocation pattern appears in response to the strong te ...

AMER CHEMICAL SOC2020

On machine learning force fields for metallic nanoparticles

Kevin Rossi

Machine learning algorithms have recently emerged as a tool to generate force fields which display accuracies approaching the ones of the ab-initio calculations they are trained on, but are much faster to compute. The enhanced computational speed of machin ...

2019

i-PI 2.0: A universal force engine for advanced molecular simulations

Michele Ceriotti, Anne-Clémence Corminboeuf, David Mark Wilkins, Bingqing Cheng, Venkat Kapil, Mariana Rossi Carvalho, Riccardo Petraglia, Benjamin Aaron Helfrecht, Robert Horst Meissner

Progress in the atomic-scale modeling of matter over the past decade has been tremendous. This progress has been brought about by improvements in methods for evaluating interatomic forces that work by either solving the electronic structure problem explici ...

ELSEVIER SCIENCE BV2019

Predicting homogeneous nucleation rate from atomistic simulations

Bingqing Cheng

Predictive modelling and quantitative understanding of nucleation is essential for predicting phase transformation processes in nature and precisely controlling material synthesis and processing. Atomistic modeling is a powerful tool for capturing the dyna ...

EPFL2019

Probing the reconstructed Fermi surface of antiferromagnetic BaFe2As2 in one domain

A fundamental part of the puzzle of unconventional superconductivity in the Fe-based superconductors is the understanding of the magnetic and nematic instabilities of the parent compounds. The issues of which of these can be considered the leading instabil ...

Springer2019

Observation of charge-transfer-driven antiferroelectricity in 3d-pyrochlore multiferroic Cu2OCl2

Helmuth Berger

Very recently, multiferroic behavior close to the boiling temperature of liquid nitrogen was reported in oxohalide-based Cu2OCl2. In this study, we have established yet another novel mechanism for the origin of charge ordering in multiferroic Cu2OCl2. The ...

ELSEVIER SCIENCE BV2019

Photocarrier-induced band-gap renormalization and ultrafast charge dynamics in black phosphorus

Majed Chergui, Marco Grioni, Alberto Crepaldi, Michele Puppin, Gianmarco Gatti, Steven Roth

With its tunable band-gap and its unique optical and electronic properties black phosphorus (BP) opens exciting opportunities for optoelectronic nanotechnology. The band-gap extends from the visible to the mid-infrared spectral range, as a function of samp ...

2019

Material Parameter Extraction for Complex AlScN Thin Film Using Dual Mode Resonators in Combination with Advanced Microstructural Analysis and Finite Element Modeling

Paul Muralt, Thomas La Grange, Vladimir Pashchenko, Fazel Parsapour, Silviu Cosmin Sandu

Accurate property determination of the piezoelectric thin film material Al(1-x)Sc(x)N is necessary for designing the next generation of radio frequency resonators in mobile communication, and for testing results of ab initio calculations. Sound velocity an ...

WILEY2019