Real-time Ginzburg-Landau theory for bosons in optical lattices
- Within the Schwinger-Keldysh formalism we derive a Ginzburg-Landau theory for the Bose-Hubbard model which describes the real-time dynamics of the complex order parameter field. Analyzing the excitations in the vicinity of the quantum phase transitions it turns out that particle/hole dispersions in the Mott phase map continuously onto corresponding amplitude/phase excitations in the superfluid phase. Furthermore, in the superfluid phase we find a sound mode, which is in accordance with recent Bragg spectroscopy measurements in the Bogoliubov regime, as well as an additional gapped mode, which seems to have been detected via lattice modulation.
| Author details: | T. D. Grass, Francisca E. A. dos Santos, Axel Pelster |
|---|---|
| DOI: | https://doi.org/10.1134/S1054660X11150096 |
| ISSN: | 1054-660X |
| ISSN: | 1555-6611 |
| Title of parent work (English): | Laser physics |
| Publisher: | IOP Publ. Ltd. |
| Place of publishing: | Bristol |
| Publication type: | Article |
| Language: | English |
| Year of first publication: | 2011 |
| Publication year: | 2011 |
| Release date: | 2017/03/26 |
| Volume: | 21 |
| Issue: | 8 |
| Number of pages: | 5 |
| First page: | 1459 |
| Last Page: | 1463 |
| Funding institution: | German Academic Exchange Service (DAAD); German Research Foundation (DFG) within the Collaborative Research Center [SFB/TR12] |
| Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
| Peer review: | Referiert |
