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arXiv · 1909.01551

Carrier dynamics in ultrathin gold nanowires: Role of Auger processes

Gyan Prakash·Subhajit Kundu·Ahin Roy·Abhishek K. Singh·N. Ravishankar·A. K. Sood
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Abstract

Carrier dynamics in metallic nanostructures is strongly influenced by their confining dimensions. Gold nanoparticles of size $\sim 2$ nm lie at the boundary separating metallic and non-metallic behavior. In this work, we report carrier dynamics in high aspect ratio ultrathin gold nanowires (Au-UNWs) of average diameter $\sim$2 nm using pump (3.1 eV) and coherent white light continuum as probe in the spectral range of 1.15 eV to 2.75 eV. The transient carrier dynamics in Au-UNWs under extreme excitation regime is slower than predicted by the often used two temperature model. We identify Auger-assisted carrier heating process which slows down the hot carrier cooling dynamics. The rate equation model fitted to the data yields an estimate of Auger coefficient for gold nanostructures.

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Gyan Prakash, Subhajit Kundu, Ahin Roy, Abhishek K. Singh, N. Ravishankar, A. K. Sood. 2019-09-04. Carrier dynamics in ultrathin gold nanowires: Role of Auger processes. https://arxiv.org/abs/1909.01551

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