The Amplitude Mode in the Quantum Phase Model
Other Condensed Matter
2008-02-08 v3
Abstract
We derive the collective low energy excitations of the quantum phase model of interacting lattice bosons within the superfluid state using a dynamical variational approach. We recover the well known sound (or Goldstone) mode and derive a gapped (Higgs type) mode that was overlooked in previous studies of the quantum phase model. This mode is relevant to ultracold atoms in a strong optical lattice potential. We predict the signature of the gapped mode in lattice modulation experiments and show how it evolves with increasing interaction strength.
Cite
@article{arxiv.0709.4436,
title = {The Amplitude Mode in the Quantum Phase Model},
author = {S. D. Huber and B. Theiler and E. Altman and G. Blatter},
journal= {arXiv preprint arXiv:0709.4436},
year = {2008}
}
Comments
4 pages, 3 figures