Ultrafast Plasmonics Beyond the Perturbative Regime: Breaking the Electronic-Optical Dynamics Correspondence

Autor: Andrea Schirato, Giulia Crotti, Mychel Gonçalves Silva, Danielle Cristina Teles-Ferreira, Cristian Manzoni, Remo Proietti Zaccaria, Paolo Laporta, Ana Maria de Paula, Giulio Cerullo, Giuseppe Della Valle
Jazyk: angličtina
Předmět:
Zdroj: Nano Letters. 22(7):2748-2754
ISSN: 1530-6992
1530-6984
DOI: 10.1021/acs.nanolett.1c04608
Popis: The transient optical response of plasmonic nanostructures has recently been the focus of extensive research. Accurate prediction of the ultrafast dynamics following excitation of hot electrons by ultrashort laser pulses is of major relevance in a variety of contexts from the study of light harvesting and photocatalytic processes to nonlinear nanophotonics and the all-optical modulation of light. So far, all studies have assumed the correspondence between the temporal evolution of the dynamic optical signal, retrieved by transient absorption spectroscopy, and that of the photoexcited hot electrons, described in terms of their temperature. Here, we show both theoretically and experimentally that this correspondence does not hold under a nonperturbative excitation regime. Our results indicate that the main mechanism responsible for the breaking of the correspondence between electronic and optical dynamics is universal in plasmonics, being dominated by the nonlinear smearing of the Fermi-Dirac occupation probability at high hot-electron temperatures.
Databáze: OpenAIRE