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Title: Generation of fast photoelectrons in strong-field emission from metal nanoparticles
We investigated the generation and control of fast photoelectrons (PEs) by exposing plasmonic nanoparticles (NPs) to short infrared (IR) laser pulses with peak intensities between 1012and 3 × 1013 W/cm2. Our measured and numerically simulated PE momentum distributions demonstrate the extent to which PE yields and cutoff energies are controlled by the NP size, material, and laser peak intensity. For strong-field photoemission from spherical silver, gold, and platinum NPs with diameters between 10 and 100 nm our results confirm and surpass extremely high PEs cutoff energies, up to several hundred times the incident laser-pulse ponderomotive energy, found recently for gold nanospheres [Saydanzad et al., Nanophotonics12, 1931 (2023)]. As reported previously for dielectric NPs [Rupp et al., J. Mod. Opt.64, 995 (2017)], at higher intensities the cutoff energies we deduce from measured and simulated PE spectra tend to converge to a metal-independent limit. We expect these characteristics of light-induced electron emission from prototypical plasmonic metallic nanospheres to promote the understanding of the electronic dynamics in more complex plasmonic nanostructures and the design of nanoscale light-controlled plasmonic electron sources for photoelectronic devices of applied interest.  more » « less
Award ID(s):
2409183 2110633
PAR ID:
10592826
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
De Gruyter
Date Published:
Journal Name:
Nanophotonics
Volume:
14
Issue:
9
ISSN:
2192-8614
Page Range / eLocation ID:
1355 to 1364
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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