Electron cascades and secondary electron emission in graphene under energetic ion irradiation

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F21%3A00546981" target="_blank" >RIV/61389021:_____/21:00546981 - isvavai.cz</a>

Alternative codes found

RIV/68378271:_____/21:00545281

Result on the web

<a href="https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.224306" target="_blank" >https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.224306</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevB.103.224306" target="_blank" >10.1103/PhysRevB.103.224306</a>

Result language

angličtina

Original language name

Electron cascades and secondary electron emission in graphene under energetic ion irradiation

Original language description

Highly energetic ions traversing a two-dimensional material such as graphene produce strong electronic excitations. Electrons excited to energy states above the work function can give rise to secondary electron emission, reducing the amount of energy that remains in graphene after the ion impact. Electrons can be either emitted (kinetic energy transfer) or captured by the passing ion (potential energy transfer). To elucidate this behavior that is absent in three-dimensional materials, we simulate the electron dynamics in graphene during the first femtoseconds after ion impact. We employ two conceptually different computational methods: a Monte Carlo (MC)-based one, where electrons are treated as classical particles, and time-dependent density functional theory (TDDFT), where electrons are described quantum mechanically. We observe that the linear dependence of electron emission on deposited energy, emerging from MC simulations, becomes sublinear and closer to the TDDFT data when the electrostatic interactions of emitted electrons with graphene are taken into account via complementary particle-in-cell simulations. Our TDDFT simulations show that the probability for electron capture decreases rapidly with increasing ion velocity, whereas secondary electron emission dominates in the high-velocity regime. We estimate that these processes reduce the amount of energy deposited in the graphene layer by 15%-65%, depending on the ion and its velocity. This finding clearly shows that electron emission must be taken into consideration when modeling damage production in two-dimensional materials under ion irradiation.

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

10305 - Fluids and plasma physics (including surface physics)

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2021

Confidentiality

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

Name of the periodical

Physical Review B

ISSN

2469-9950

e-ISSN

2469-9969

Volume of the periodical

103

Issue of the periodical within the volume

22

Country of publishing house

US - UNITED STATES

Number of pages

13

Pages from-to

224306

UT code for WoS article

000662302600001

EID of the result in the Scopus database

2-s2.0-85108244408