Quasiparticle lifetime in a finite system: A nonperturbative approach

Boris L. Altshuler, Yuval Gefen, Alex Kamenev, Leonid S. Levitov

Research output: Contribution to journalArticlepeer-review

473 Scopus citations


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. In the delocalized regime, each eigenstate is a superposition of states with very different quasiparticle content. The transition energy is εc≈Δ(g/ln g)1/2, where Δ is mean level spacing, and g is the dimensionless conductance. Near εc there is a broad critical region not described by the golden rule.

Original languageEnglish (US)
Pages (from-to)2803-2806
Number of pages4
JournalPhysical review letters
Issue number14
StatePublished - Apr 7 1997


Dive into the research topics of 'Quasiparticle lifetime in a finite system: A nonperturbative approach'. Together they form a unique fingerprint.

Cite this