Publications de Samuel Poncé | EPFL Graph Search

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

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

Long-range electrostatic contribution to electron-phonon couplings and mobilities of two-dimensional and bulk materials

Nicola Marzari, Marco Gibertini, Samuel Poncé, Massimiliano Stengel

Charge transport plays a crucial role in manifold potential applications of two-dimensional materials, in-cluding field-effect transistors, solar cells, and transparent conductors. At most operating temperatures, charge transport is hindered by scattering ...

AMER PHYSICAL SOC2023

Electronic Structure of Few-Layer Black Phosphorus from & mu;-ARPES

Nicola Marzari, Marco Gibertini, Samuel Poncé, Christophe Berthod

Black phosphorus (BP) stands out among two-dimensional(2D) semiconductorsbecause of its high mobility and thickness dependent direct band gap.However, the quasiparticle band structure of ultrathin BP has remainedinaccessible to experiment thus far. Here we ...

AMER CHEMICAL SOC2023

General invariance and equilibrium conditions for lattice dynamics in 1D, 2D, and 3D materials

Nicola Marzari, Changpeng Lin, Samuel Poncé

The long-wavelength behavior of vibrational modes plays a central role in carrier transport, phonon-assisted optical properties, superconductivity, and thermomechanical and thermoelectric properties of materials. Here, we present general invariance and equ ...

NATURE PORTFOLIO2022

Ultrafast photo-induced phonon hardening due to Pauli blocking in MAPbI(3) single-crystal and polycrystalline perovskites

Samuel Poncé, Feliciano Giustino

Metal-halide perovskite semiconductors have attracted intense interest over the past decade, particularly for applications in photovoltaics. Low-energy optical phonons combined with significant crystal anharmonicity play an important role in charge-carrier ...

IOP PUBLISHING LTD2021

Common workflows for computing material properties using different quantum engines

Berend Smit, Nicola Marzari, Giovanni Pizzi, Martin Uhrin, Marnik Bercx, Austin Jacob Zadoks, Kristjan Eimre, Samuel Poncé, Aliaksandr Yakutovich, Sebastiaan Philippe Huber

The prediction of material properties based on density-functional theory has become routinely common, thanks, in part, to the steady increase in the number and robustness of available simulation packages. This plurality of codes and methods is both a boon ...

2021

Virtual Computational Chemistry Teaching Laboratories-Hands-On at a Distance

Nicola Marzari, Giovanni Pizzi, Iurii Timrov, Marnik Bercx, Samuel Poncé, Christoph Leopold Talirz, Francisco Fernando Ramirez

The COVID-19 pandemic disrupted chemistry teaching practices globally as many courses were forced online, necessitating adaptation to the digital platform. The biggest impact was to the practical component of the chemistry curriculum-the so-called wet lab. ...

AMER CHEMICAL SOC2021

First-principles predictions of Hall and drift mobilities in semiconductors

Nicola Marzari, Samuel Poncé

Carrier mobility is at the root of our understanding of electronic devices. We present a unified methodology for the parameter-free calculations of phonon-limited drift and Hall carrier mobilities in real materials within the framework of the Boltzmann tra ...

AMER PHYSICAL SOC2021

Importance of Long-Range Channel Sr Displacements for the Narrow Emission in Sr[Li2Al2O2N2]:Eu2+ Phosphor

Samuel Poncé

The recently discovered Sr[Li2Al2O2N2]:Eu2+ red phosphor, candidate for the next generation of eco-efficient white light-emitting diodes, exhibits excellent emission spectral position and exceptionally small linewidth. It belongs to the UCr4C4-structure fa ...

WILEY-V C H VERLAG GMBH2021

Limits to Electrical Mobility in Lead-Halide Perovskite Semiconductors

Samuel Poncé

Semiconducting polycrystalline thin films are cheap to produce and can be deposited on flexible substrates, yet high-performance electronic devices usually utilize single-crystal semiconductors, owing to their superior charge-carrier mobilities and longer ...

2021