Contribution of inter- and intraband transitions into electron-phonon coupling in metals

TL;DR

This paper introduces a computational approach to analyze how inter- and intraband electron transitions contribute to electron-phonon coupling in metals, revealing their different roles and temperature dependencies in various materials.

Contribution

It applies a new tight-binding molecular dynamics method to quantify partial contributions of inter- and intraband transitions to electron-phonon coupling in metals and alloys.

Findings

Interband scattering is significant in Al and AlCu.

Intraband $d-d$ transitions dominate in Au and Cu.

Transitions show different temperature dependencies.

Abstract

We recently developed an approach for calculation of the electron-phonon (electron-ion in a more general case) coupling in materials based on tight-binding molecular dynamics simulations. In the present work we utilize this approach to study partial contributions of inter- and intraband electron scattering events into total electron-phonon coupling in Al, Au, Cu elemental metals and in AlCu alloy. We demonstrate that the interband scattering plays an important role in electron-ion energy exchange process in Al and AlCu, whereas intraband $d-d$ transitions are dominant in Au and Cu. Moreover, inter- and intraband transitions exhibit qualitatively different dependencies on the electron temperature. Our findings should be taken into account for interpretation of experimental results on electron-phonon coupling parameter.