carrier dynamics in ultrathin gold nanowires: role of auger processes

Carrier dynamics in metallic nanostructures is strongly influenced by their confining dimensions. gold nanoparticles of size $sim ~2$ nm which fill the transition space separating metallic and non-metallic behavior. in this work, we report carrier dynamics in high aspect ratio ultrathin gold nanowires (au-unws) of average diameter $sim $ 2 nm using pump (3.1 ev) and coherent white light continuum as probe in the spectral range of 1.15 to 2.75 ev. the transient carrier dynamics in au-unws under extreme excitation regime is slower than predicted by the often used two-temperature model. we identify auger-assisted carrier heating process which slows down the hot carrier cooling dynamics. the rate equation model fitted to the data yields an estimate of auger coefficient for gold nanostructures.