Mott insulator to superfluid transition in the Bose-Hubbard model: a strong-coupling approach
| dc.creator | Sengupta, K. | |
| dc.creator | Dupuis, N. | |
| dc.date | 2004-12-08 | |
| dc.date | 2005-04-15 | |
| dc.date.accessioned | 2026-07-07T06:21:46Z | |
| dc.date.available | 2026-07-07T06:21:46Z | |
| dc.description | We present a strong-coupling expansion of the Bose-Hubbard model which describes both the superfluid and the Mott phases of ultracold bosonic atoms in an optical lattice. By performing two successive Hubbard-Stratonovich transformations of the intersite hopping term, we derive an effective action which provides a suitable starting point to study the strong-coupling limit of the Bose-Hubbard model. This action can be analyzed by taking into account Gaussian fluctuations about the mean-field approximation as in the Bogoliubov theory of the weakly interacting Bose gas. In the Mott phase, we reproduce results of previous mean-field theories and also calculate the momentum distribution function. In the superfluid phase, we find a gapless spectrum and compare our results with the Bogoliubov theory. | |
| dc.description | 8 pages, 6 figures; (v2) Two references added | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0412204 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0412204 | |
| dc.identifier | Phys. Rev. A 71, 033629 (2005) | |
| dc.identifier | doi:10.1103/PhysRevA.71.033629 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/95709 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Mott insulator to superfluid transition in the Bose-Hubbard model: a strong-coupling approach | |
| dc.type | text |