Quasiparticle Lifetime in a Finite System: A Nonperturbative Approach
Quasiparticle Lifetime in a Finite System: A Nonperturbative Approach
The problem of electron-electron lifetime in a quantum dot is studied beyond perturbation theory by mapping onto the problem of localization in the Fock space. Localized and delocalized regimes are identified, corresponding to quasiparticle spectral peaks of zero and finite width, respectively. In the localized regime, quasiparticle states are single-particle-like. …