Anistropic electron-electron and electron-phonon scattering rates in aluminium from high-precision RFSE measurements between 0.2 and 10 K

Abstract

High-precision low-temperature radio frequency size effect (RFSE) experiments have been carried out to extract local values of the electron-phonon (e-p) and electron-electron (e-e) scattering rates (SRs) in aluminium. The RF was varied to help separate these two contributions. For the first time an unexpected large anisotropy of the e-e SR has been observed, suggesting that the phonon mediated e-e SR dominates the Coulomb contribution. Comparison of the experimental data with recent calculated values of the e-e SR confirm the importance of this mechanism.