Dynamic density-density correlations in interacting Bose gases on optical lattices

Abstract

In order to identify possible experimental signatures of the superfluid to Mott-insulator quantum phase transition we calculate the charge structure factor $S(k,\omega )$ for the one-dimensional Bose-Hubbard model using the dynamical density-matrix renormalisation group (DDMRG) technique. Particularly we analyse the behaviour of $S(k,\omega )$ by varying---at zero temperature---the Coulomb interaction strength within the first Mott lobe. For strong interactions, in the Mott-insulator phase, we demonstrate that the DDMRG results are well reproduced by a strong-coupling expansion, just as the quasi-particle dispersion. In the superfluid phase we determine the linear excitation spectrum near $k=0$ and compare the DDMRG data with results from mean-field theory.

4 pages, 3 figures, final version, accepted for publication in Journal of Physics: Conference Series

References in corpus (7)

• Many-Body Physics with Ultracold Gases
• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• One dimensional Bosons: From Condensed Matter Systems to Ultracold Gases
• Dynamical properties of ultracold bosons in an optical lattice
• Dynamic properties of the one-dimensional Bose-Hubbard model
• Excitation spectra of strongly correlated lattice bosons and polaritons
• Density-matrix renormalisation group approach to quantum impurity problems

Cited by in corpus (4)

• Spectral and Entanglement Properties of the Bosonic Haldane Insulator
• Unraveling the Excitation Spectrum of Many-Body Systems from Quantum Quenches
• Strongly repulsive anyons in one dimension
• Superexchange Liquefaction of Strongly Correlated Lattice Dipolar Bosons