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arXiv · 2107.08782

Quantitative Ultrafast Electron-Temperature Dynamics in Photo-Excited Au Nanoparticles

Maria Sygletou·Stefania Benedetti·Marzia Ferrera·Gian Marco Pierantozzi·Riccardo Cucini·Giuseppe Della Valle·Pietro Carrara·Alessandro De Vita·Alessandro di Bona·Piero Torelli·Daniele Catone·Giancarlo Panaccione·Maurizio Canepa·Francesco Bisio
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Abstract

The femtosecond evolution of the electronic temperature of laser-excited gold nanoparticles is measured, by means of ultrafast time-resolved photoemission spectroscopy induced by extreme-ultraviolet radiation pulses. The temperature of the electron gas is deduced by recording and fitting high-resolution photo emission spectra around the Fermi edge of gold nanoparticles providing a direct, unambiguous picture of the ultrafast electron-gas dynamics. These results will be instrumental to the refinement of existing models of femtosecond processes in laterally-confined and bulk condensed-matter systems, and for understanding more deeply the role of hot electrons in technological applications.

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Maria Sygletou, Stefania Benedetti, Marzia Ferrera, Gian Marco Pierantozzi, Riccardo Cucini, Giuseppe Della Valle, Pietro Carrara, Alessandro De Vita, Alessandro di Bona, Piero Torelli, Daniele Catone, Giancarlo Panaccione, Maurizio Canepa, Francesco Bisio. 2021-06-30. Quantitative Ultrafast Electron-Temperature Dynamics in Photo-Excited Au Nanoparticles. https://doi.org/10.1002/smll.202100050

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