Terahertz spectroscopy is a perfect tool to investigate the electronic intraband conductivity of graphene, but a phenom-enological model (Drude-Smith) is often needed to describe disorder. By studying the THz response of isotropically strained polycrystalline graphene and using a fully atomistic computational approach to fit the results, we demonstrate here the connection between the Drude-Smith parameters and the microscopic behavior. Importantly, we clearly show that the strain-induced changes in the conductivity originate mainly from the increased separation between the single-crystal grains, leading to enchanced localization of the plasmon excitations. Only at the lowest strain values explored, a behavior consistent with the deformation of the individual grains can instead be observed.
Strain-Induced Plasmon Confinement in Polycrystalline Graphene
Zanotto, SimonePrimo
;Cappelli, Chiara;Tredicucci, Alessandro
Penultimo
;Toncelli, AlessandraUltimo
2023-01-01
Abstract
Terahertz spectroscopy is a perfect tool to investigate the electronic intraband conductivity of graphene, but a phenom-enological model (Drude-Smith) is often needed to describe disorder. By studying the THz response of isotropically strained polycrystalline graphene and using a fully atomistic computational approach to fit the results, we demonstrate here the connection between the Drude-Smith parameters and the microscopic behavior. Importantly, we clearly show that the strain-induced changes in the conductivity originate mainly from the increased separation between the single-crystal grains, leading to enchanced localization of the plasmon excitations. Only at the lowest strain values explored, a behavior consistent with the deformation of the individual grains can instead be observed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.