Role of occupieddstates in the relaxation of hot electrons in Au

We present first-principles calculations of electron-electron scattering rates of low-energy electrons in Au. Our full band-structure calculations indicate that a major contribution from occupied d states participating in the screening of electron-electron interactions yields lifetimes of electrons in Au with energies of 1.0--3.0 eV above the Fermi level that are larger than those of electrons in a free-electron gas by a factor of ~4.5. This prediction is in agreement with a recent experimental study of ultrafast electron dynamics in Au(111) films [J. Cao et al., Phys. Rev. B 58, 10 948 (1998)], where electron transport has been shown to play a minor role in the measured lifetimes of hot electrons in this material.