In transmission electron energy loss (EEL) spectroscopy, the cross section in two dimensions (2D) is quenched by kinematic effects once the momentum transfer becomes smaller than a critical value set by qz, the momentum loss parallel to the beam. Our highly momentum (Δq=0.02Å-1) and energy (ΔE=45 meV) resolved setup is instrumental in delivering the experimental verification of quenched 2D EEL spectra on freestanding graphene at momentum transfers q below 0.06Å-1. We retrieve the intrinsic uniform dielectric response of graphene from measured spectra by quantifying the kinematic suppression.
Direct observation of the vanishing electron energy loss spectroscopy cross section in graphene / Guandalini, A.; Senga, R.; Lin, Y. -C.; Suenaga, K.; Barone, P.; Mauri, F.; Pichler, T.; Kramberger, C.. - In: PHYSICAL REVIEW. B. - ISSN 2469-9950. - 111:4(2025). [10.1103/PhysRevB.111.L041401]
Direct observation of the vanishing electron energy loss spectroscopy cross section in graphene
Guandalini A.;Mauri F.;
2025
Abstract
In transmission electron energy loss (EEL) spectroscopy, the cross section in two dimensions (2D) is quenched by kinematic effects once the momentum transfer becomes smaller than a critical value set by qz, the momentum loss parallel to the beam. Our highly momentum (Δq=0.02Å-1) and energy (ΔE=45 meV) resolved setup is instrumental in delivering the experimental verification of quenched 2D EEL spectra on freestanding graphene at momentum transfers q below 0.06Å-1. We retrieve the intrinsic uniform dielectric response of graphene from measured spectra by quantifying the kinematic suppression.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
