Publications associées à Accuracy of GW for calculating defect energy levels in solids

Accelerating the theoretical study of Li-polysulfide adsorption on single-atom catalysts via machine learning approaches

Li-S batteries are a promising alternative to Li-ion batteries, offering large energy storage capacity and wide operating temperature range. However, their performance is heavily affected by the Li-polysulfide (LiPS) shuttling. Computational screening of L ...

WILEY2022

Stoichiometry modulates the optoelectronic functionality of Zinc Phosphide (Zn3-xP2+x)

Anna Fontcuberta i Morral, Elias Zsolt Stutz, Jean-Baptiste Leran, Mahdi Zamani, Maria Chiara Spadaro, Simon Robert Escobar Steinvall, Santhanu Panikar Ramanandan, Rajrupa Paul, Diego Armando Sandoval Salaiza, Mirjana Dimitrievska, Mischa Samuel Flór

Predictive synthesis–structure–property relationships are at the core of materials design for novel applications. In this regard, correlations between the compositional stoichiometry variations and functional properties are essential for enhancing the perf ...

2022

Pivotal Role of Intersite Hubbard Interactions in Fe-Doped alpha-MnO2

Iurii Timrov

We present a first-principles investigation of the structural, electronic, and magnetic properties of the pristine and Fe-doped alpha-MnO2 using density-functional theory with extended Hubbard functionals. The onsite U and intersite V Hubbard parameters ar ...

AMER CHEMICAL SOC2022

Magnetic Properties of Surface Adsorbed Metal Adatoms and Dimers

Dante Philippe Sblendorio

This thesis investigates the magnetic properties of single atoms and dimers adsorbed on graphene and oxide decoupling layers supported by single crystal metal substrates, using scanning tunneling microscopy (STM) and spin-polarized scanning tunneling micro ...

EPFL2022

Imaging Nonradiative Point Defects Buried in Quantum Wells Using Cathodoluminescence

Jean-François Carlin, Nicolas Grandjean, Raphaël Butté, Duncan Thomas Lindsay Alexander, Wei Liu, Wei Liu, Thomas Fjord Kjaersgaard Weatherley

Crystallographic point defects (PDs) can dramatically decrease the efficiency of optoelectronic semiconductor devices, many of which are based on quantum well (QW) heterostructures. However, spatially resolving individual nonradiative PDs buried in such QW ...

AMER CHEMICAL SOC2021

Gate Control of Spin-Layer-Locking FETs and Application to Monolayer LuIO

Nicola Marzari, Antimo Marrazzo, Thibault Daniel Pierre Sohier, Rong Zhang

A recent 2D spinFET concept proposes to switch electrostatically between two separate sublayers with strong and opposite intrinsic Rashba effects, exploiting the spin-layer-locking mechanism in centrosymmetric materials with local dipole fields. Here, we p ...

AMER CHEMICAL SOC2021

Theoretical maximum photogeneration efficiency and performance characterization of InxGa1-xN/Si tandem water-splitting photoelectrodes

Yannick Kenneth Gaudy, Sophia Haussener

InxGa1-xN is a promising material for flexible and efficient water-splitting photoelectrodes since the bandgap is tunable by modifying the indium content. We investigate the potential of an InxGa1-xN/Si tandem used as a water-splitting photoelectrode. We p ...

2020

Optoelectronic and magnetic properties induced by atomic defects in two-dimensional semiconductors

Alessio Scavuzzo

Two-dimensional (2D) materials have attracted increasing attention over the last decade owing to their remarkable mechanical, electrical and optical properties. Following the groundbreaking discovery of graphene, a plethora of other atomically-thin materia ...

EPFL2020

Nature of native atomic defects in ZrTe5 and their impact on the low-energy electronic structure

Helmuth Berger, Oleg Yazyev, Ana Akrap, Shengnan Zhang

Over the past decades, investigations of the anomalous low-energy electronic properties of ZrTe5 have reached a wide array of conclusions. An open question is the growth method's impact on the stoichiometry of ZrTe5 samples, especially given the very small ...

AMER PHYSICAL SOC2020

Defect Formation Energies of Interstitial C, Si, and Ge Impurities in beta-Ga2O3

Alfredo Pasquarello, Assil Bouzid

Formation energies of C, Si, and Ge defects in beta-Ga2O3 are studied through hybrid functional calculations. The interstitial defects of these elements generally occur at higher energies than their substitutional counterparts, but are more stable at low F ...

WILEY-V C H VERLAG GMBH2019

Alignment of energy levels in amorphous oxides and at semiconductor-water interfaces

Zhendong Guo

We conduct a detailed investigation of defects in two representative amorphous oxides: amorphous Al2O3 (am-Al2O3) and TiO2 (am-TiO2), by combining ab initio molecular dynamics (MD) simulations and hybrid functional calculations. Our results indicate that o ...

EPFL2019

Extrinsic Defects in Amorphous Oxides: Hydrogen, Carbon, and Nitrogen Impurities in Alumina

Alfredo Pasquarello, Zhendong Guo, Francesco Ambrosio

We present a procedure for addressing extrinsic defects in amorphous oxides, in which the most stable defect configurations are identified through ab initio molecular dynamics in various charge states and studied through hybrid functional calculations. The ...

American Physical Society (APS)2019

Crystalline and correlated phases in two-dimensional transition metal dichalcogenides

Diego José Pasquier

This thesis is dedicated to the study of various aspects of the electronic structure of two-dimensional transition metal dichalcogenides (TMDs) of chemical composition MX

_2

(where M is a transition metal atom and X= S, Se, Te), using a combination of \te ...

EPFL2019

Template-assisted grown III-V semiconductor nanowires: A transmission electron microscopy study

Nicolas Bologna

III-V semiconductor nanowires are, due to their unique properties, one of the most promising nanostructures developed in the last decades. However, the realization of commercial devices made of III-V nanowires, such as transistors and solar cells, has not ...

EPFL2019

Advanced Computational Methods for NMR Crystallography

Albert Hofstetter

Knowledge of the atomic-level structure is key to understanding and predicting properties of materials. X-ray diffraction (XRD) is the methods of choice for structures containing well-defined long-range order. However, many materials contain various degree ...

EPFL2019

High-permeance polymer-functionalized single-layer graphene membranes that surpass the postcombustion carbon capture target

Mounir Driss Mensi, Emad Oveisi, Kumar Varoon Agrawal, Shiqi Huang, Guangwei He, Jing Zhao, Luis Francisco Villalobos Vazquez de la Parra

Membrane-based postcombustion carbon capture can reduce the capture penalty in comparison to absorbent-based separation. To realize this, high-performance membranes are urgently needed with a CO2 permeance exceeding 1000 gas permeation units or GPU, and a ...

2019

Hydrogen Diffusion and Trapping in α-Iron: The Role of Quantum and Anharmonic Fluctuations

Michele Ceriotti, Bingqing Cheng

We investigate the thermodynamics and kinetics of a hydrogen interstitial in magnetic α-iron, taking account of the quantum fluctuations of the proton as well as the anharmonicities of lattice vibrations and hydrogen hopping. We show that the diffusivity o ...

2018

Atomistic Simulations of The Structure of Calcium Silicate Hydrates: Interlayer Positions, Water Content And A General Structural Brick Model

Aslam Kunhi Mohamed

Portland cement has been in use by human civilization for over a century. Yet, we do not fully understand its hydration reaction mechanisms due to the complexity of the system and its continued reaction over time making it hard to study it experimentally. ...

EPFL2018

Grain boundaries and quantum transport in monolayer MoS2

Kolyo Marinov

The growing research on two-dimensional materials reveals their exceptional physical properties and enormous potential for future applications and investigation of advanced physics phenomena. They represent the ultimate limit in terms of active channel thi ...

EPFL2018

Electronic Transport in 2D Materials with Strong Spin-orbit Coupling

Artem Pulkin

The thesis describes the computational study of structural, electonic and transport properties of monolayer transition metal dichalcogenides (TMDs) in the stable 2H and the metastable 1T' phases. Several aspects have been covered by the study including the ...

EPFL2017