We study the nonlinear response of collective optical resonances in linear atomic chains with metallic, semiconducting, and topologically insulating character to low-energy free electrons. The nonlinearity, which manifests in the amplitude and frequency of resonant features in cathodoluminescence and electron energy-loss spectra, is shown to depend on the speed and trajectory of the excitation as well as the length and electronic structure of the chain. Time-domain analysis of charge carrier dynamics within the atomic chain reveals that the Fermi velocity sets the threshold speed for triggering an electron-induced nonlinear response, a phenomenon which can elucidate nonlinear light-matter interactions on the nanoscale.
Bibliografisk noteFunding Information:
The authors thank C. Wolff for insightful and enjoyable discussions. J.D.C. is a Sapere Aude research leader supported by VILLUM FONDEN (Grant No. 16498) and Independent Research Fund Denmark (Grant No. 0165-00051B). The Center for Polariton-Driven Light-Matter Interactions (POLIMA) is funded by the Danish National Research Foundation (Project No. DNRF165). Part of the computation in this project was performed on the DeiC Large Memory HPC system managed by the eScience Center at the University of Southern Denmark.
© 2023 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.