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Ultrafast Surface Plasmon Probing of Interband and Intraband Hot Electron Excitations.

ABSTRACT: Upon the interaction of light with metals, nonthermal electrons are generated with intriguing transient behavior. Here, we present femtosecond hot electron probing in a noveloptical pump/plasmon probe scheme. With this, we probed ultrafast interband and intraband dynamics with 15 nm interface selectivity, observing a two-component-decay of hot electron populations. Results are in good agreement with a three-temperature model of the metal; thus, we could attribute the fast (∼100 fs) decay to the thermalization of hot electrons and the slow (picosecond) decay to electron-lattice thermalization. Moreover, we could modulate the transmission of our plasmonic channel with ∼40% depth, hinting at the possibility of ultrafast information processing applications with plasmonic signals.

SUBMITTER: Sandor P

PROVIDER: S-EPMC11229057 | biostudies-literature | 2024 Jul

REPOSITORIES: biostudies-literature

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Ultrafast Surface Plasmon Probing of Interband and Intraband Hot Electron Excitations.

Sándor Péter P Lovász Béla B Budai Judit J Pápa Zsuzsanna Z Dombi Péter P

Nano letters 20240604 26

Upon the interaction of light with metals, nonthermal electrons are generated with intriguing transient behavior. Here, we present femtosecond hot electron probing in a noveloptical pump/plasmon probe scheme. With this, we probed ultrafast interband and intraband dynamics with 15 nm interface selectivity, observing a two-component-decay of hot electron populations. Results are in good agreement with a three-temperature model of the metal; thus, we could attribute the fast (∼100 fs) decay to the ...[more]

PMID: 38833525

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