Direct observation of the vanishing EELS cross section in graphene

2024/06/05 by Alberto Guandalini, Ryosuke Senga, Guandalini, Alberto +13
Chemical Engineering · Materials Science · #Analytical Chemistry and Sensors #FOS: Physical sciences #Graphene research and applications #High voltage insulation and dielectric phenomena #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Other Condensed Matter (cond-mat.other)

paper · pdf · doi:10.48550/arxiv.2406.02998

openalex publication_date 2024/06/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03

Abstract

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 (Δq = 0.02~Å^-1) and energy (ΔE = 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 0.06Å^-1. We retrieve the intrinsic uniform dielectric response of graphene from measured spectra by quantifying the kinematic suppression.

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