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Direct Measurement of Ballistic and Diffusive Electron Transport in Gold.

ABSTRACT: We experimentally show that the ballistic length of hot electrons in laser-heated gold films can exceed ∼150 nm, which is ∼50% greater than the previously reported value of 100 nm inferred from pump-probe experiments. We also find that the mean free path of electrons at the peak temperature following interband excitation can reach upward of ∼45 nm, which is higher than the average value of 30 nm predicted from our parameter-free density functional perturbation theory. Our first-principles calculations of electron-phonon coupling reveal that the increase in the mean free path due to interband excitation is a consequence of drastically reduced electron-phonon coupling from lattice stiffening, thus providing the microscopic understanding of our experimental findings.

SUBMITTER: Karna P

PROVIDER: S-EPMC9881161 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Direct Measurement of Ballistic and Diffusive Electron Transport in Gold.

Karna Pravin P Hoque Md Shafkat Bin MSB Thakur Sandip S Hopkins Patrick E PE Giri Ashutosh A

Nano letters 20230104 2

We experimentally show that the ballistic length of hot electrons in laser-heated gold films can exceed ∼150 nm, which is ∼50% greater than the previously reported value of 100 nm inferred from pump-probe experiments. We also find that the mean free path of electrons at the peak temperature following interband excitation can reach upward of ∼45 nm, which is higher than the average value of 30 nm predicted from our parameter-free density functional perturbation theory. Our first-principles calcul ...[more]

PMID: 36598434

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