A spectroscopic method is applied to measure the inelastic quasiparticle relaxation rate in a disordered Fermi liquid. The quasiparticle relaxation rate g is deduced from the magnitude of fluctuations in the local density of states, which are probed using resonant tunneling through a localized impurity state. We study its dependence on the excitation energy E measured from the Fermi level. In a disordered metal (heavily doped GaAs) we find that g ~ E32 within the experimentally accessible energy interval, in agreement with the Altshuler-Aronov theory for electron-electron interactions in diffusive conductors.
A new method of correlation function spectroscopy has been developed by McCann (and experimentally realised by the Nanostructures group of Haug at Hannover) to measure inelastic lifetime of quasi-particles in disordered conductors at very low excitation energies. RAE_import_type : Journal article RAE_uoa_type : Physics