Groupe de Physique Statistique

Equipe 106, Institut Jean Lamour

                     
Accueil
Accès
Personnel
Publications
Articles dans des revues à comité de lecture
Lettres
Actes de conférences invités
Actes de conférences
Non publié
Thèse
Habilitation à diriger des recherches
Epistémologie, histoire des sciences
Articles à vocation pédagogique
Livres
Edition d'ouvrage
Chapitres de livre
Vulgarisation
Séminaires
Ateliers
Rencontres
Ecoles
International
Grp Travail
Theses, Postes
Enseignement

Articles dans des revues à comité de lecture

Spin decoherence due to a randomly fluctuating spin bath
Faribault A., Schuricht D.
Phys. Rev. B 88 (2013) 085323
DOI : 10.1103/PhysRevB.88.085323

We study the decoherence of a spin in a quantum dot due to its hyperfine coupling to a randomly fluctuating bath of nuclear spins. The system is modeled by the central spin model with the spin bath initially being at infinite temperature. We calculate the spectrum and time evolution of the coherence factor using a Monte Carlo sampling of the exact eigenstates obtained via the algebraic Bethe ansatz. The exactness of the obtained eigenstates allows us to study the nonperturbative regime of weak magnetic fields in a full quantum mechanical treatment. In particular, we find a large nondecaying fraction in the zero-field limit. The crossover from strong to weak fields is similar to the decoherence starting from a pure initial bath state treated previously. We compare our results to a simple semiclassical picture [Merkulov et al., Phys. Rev. B 65, 205309 (2002)] and find surprisingly good agreement. Finally, we discuss the effect of weakly coupled spins and show that they will eventually lead to complete decoherence.



Haut de page