Electron-electron scattering rate in thin metal films

The influence of the thickness of a metal film on the electron-electron scattering rate is studied in the framework of the jellium model. It is shown that a one-dimensional confinement of the electrons in the film results in a scattering rate increase by Deltav(k)/l, where v(k) is some anisotropic function of excitation wave vector k, and l is the film thickness. Our calculations show that this increase can be of the order of the bulk scattering rate itself for few-nanometer-thick films. This fact should be taken into account when interpreting experiments with ultrathin films.