Transition from a Strongly Interacting 1D Superfluid to a Mott Insulator (original) (raw)
NASA/ADS
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Abstract
We study 1D trapped Bose gases in the strongly interacting regime. The systems are created in an optical lattice and are subject to a longitudinal periodic potential. Bragg spectroscopy enables us to investigate the excitation spectrum in different regimes. In the superfluid phase a broad continuum of excitations is observed which calls for an interpretation beyond the Bogoliubov spectrum taking into account the effect of strong interactions. In the Mott insulating phase a discrete spectrum is measured. Both phases are compared to the 3D situation and to the crossover regime from 1D to 3D. The coherence length and coherent fraction of the gas are measured in all configurations. We observe signatures for increased fluctuations characteristic for 1D systems. Moreover, the collective oscillations cease near the transition to the Mott insulator phase.
Publication:
Physical Review Letters
Pub Date:
March 2004
DOI:
arXiv:
Bibcode:
Keywords:
- 05.30.Jp;
- 03.75.Kk;
- 03.75.Lm;
- 73.43.Nq;
- Boson systems;
- Dynamic properties of condensates;
- collective and hydrodynamic excitations superfluid flow;
- Tunneling Josephson effect Bose-Einstein condensates in periodic potentials solitons vortices and topological excitations;
- Quantum phase transitions;
- Condensed Matter - Soft Condensed Matter
E-Print:
4 pages