Monte Carlo simulations of measured electron energy-loss spectra of diamond and graphite: Role of dielectric-response models

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F17%3A10368804" target="_blank" >RIV/00216208:11320/17:10368804 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1016/j.carbon.2017.03.041" target="_blank" >http://dx.doi.org/10.1016/j.carbon.2017.03.041</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.carbon.2017.03.041" target="_blank" >10.1016/j.carbon.2017.03.041</a>

Result language

angličtina

Original language name

Monte Carlo simulations of measured electron energy-loss spectra of diamond and graphite: Role of dielectric-response models

Original language description

In this work we compare Monte Carlo (MC) simulations of electron-transport properties with reflection electron energy-loss measurements in diamond and graphite films. We assess the impact of different approximations of the dielectric response on the observables of interest for the characterization of carbon-based materials. We calculate the frequency-dependent dielectric response and energy-loss functions of these materials in two ways: a full ab initio approach, in which we carry out time-dependent density functional simulations in linear response for different momentum transfers, and a semi-classical model, based on the Drude-Lorentz extension to finite momenta of the optical dielectric function. Ab initio calculated dielectric functions lead to better agreement with measured energy-loss spectra compared to the widely used Drude-Lorentz model. This discrepancy is particularly evident for insulators and semiconductors beyond the optical limit (q not equal 0), where single-particle excitations become relevant. Furthermore, we show that the behaviour of the energy-loss function obtained at different accuracy levels has a dramatic effect on other physical observables, such as the inelastic mean free path and the stopping power in the low energy (&lt;100 eV) regime and thus on the accuracy of MC simulations.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10300 - Physical sciences

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2017

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Carbon

ISSN

0008-6223

e-ISSN

—

Volume of the periodical

118

Issue of the periodical within the volume

1

Country of publishing house

US - UNITED STATES

Number of pages

11

Pages from-to

299-309

UT code for WoS article

000401120800035

EID of the result in the Scopus database

—