Direct observation of the vanishing EELS cross section in graphene

Autor(en)

Alberto Guandalini, Ryosuke Senga, Yung-Chang Lin, Kazu Suenaga, Paolo Barone, Francesco Mauri, Thomas Pichler, Christian Kramberger

Abstrakt

In transmission electron energy-loss spectroscopy, the cross section in 2D is quenched by kinematic effects once the momentum transfer becomes smaller than a critical value set by $q_z$, the momentum loss parallel to the beam. Our highly momentum ($\Delta q = 0.02$~\r{A}$^{-1}$) and energy ($\Delta E = 45$~meV) resolved setup is instrumental on delivering the unprecedented experimental verification of quenched 2D EEL spectra on freestanding graphene at momentum transfers $q$ below $0.06$\r{A}$^{-1}$. We retrieve the intrinsic uniform dielectric response of graphene from measured spectra by quantifying the kinematic suppression.

Organisation(en)

Elektronische Materialeigenschaften

Externe Organisation(en)

Università degli Studi di Roma La Sapienza, National Institute of Advanced Industrial Science and Technology (AIST), Osaka University, Consiglio Nazionale delle Ricerche

Anzahl der Seiten

10

DOI

https://doi.org/10.48550/arXiv.2406.02998

Publikationsdatum

06-2024

ÖFOS 2012

103009 Festkörperphysik, 103018 Materialphysik, 103020 Oberflächenphysik

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/5ef6a8b4-193c-49ce-bd7b-a46addfd9b16