| Zugriffsnummer | 23152 |
| Dokumenttyp | Zeitschriftenartikel |
| Sprache | Englisch |
| Titel | The large system asymptotics of persistent currents in mesoscopic quantum rings |
| Autor(in); Institution |
Gendiar, Andrej; Slovak Academy of Sciences, Institute of Electrical Engineering, Bratislava, SLOVAKIA; RWTH Aachen, Institute for Theoretical Physics, Aachen, GERMANY
Krcmar, Roman; Slovak Academy of Sciences, Institute of Electrical Engineering, Bratislava, SLOVAKIA
Weyrauch, Michael; PSt, Präsidialer Stab, PTB-Braunschweig
|
| Quelle/Jahr | Physical Review B: 79 (2009), 205118-1 - 205118-11 |
| ISSN | 1098-0121 |
| DOI | |
| Verlag | Ridge, NY: APS |
| Klassifikationscode | PACS: 71.10.Pm ; PACS: 73.23.Ra ; PACS: 73.63.-b ; PACS: 05.10.Cc |
| Freie Schlagworte | electron density ; ground states ; magnetic flux ; mesoscopic systems ; persistent currents ; quantum dots ; renormalisation |
| Zusammenfassung | We consider a one-dimensional mesoscopic quantum ring filled with spinless electrons and threaded by a magnetic flux, which carries a persistent current at zero temperature. The interplay of Coulomb interactions and a single on-site impurity yields a non-trivial dependence of the persistent current on the size of the ring. We determine numerically the asymptotic power law for systems up to 32 000 sites for various impurity strengths and compare with predictions from Bethe Ansatz solutions combined with Bosonization. The numerical results are obtained using an improved functional renormalization group (fRG) method. We apply the density matrix renormalization group (DMRG) and exact diagonalization methods to benchmark the fRG calculations. We use DMRG to study the persistent current at low electron concentrations in order to extend the validity of our results to quasi-continuous systems. We briefly comment on the quality of calculated fRG ground state energies by comparison with exact DMRG data. |
