Real-Time Ginzburg-Landau Theory for Bosons in Optical Lattices

Abstract

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.

References in corpus (18)

• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Cold bosonic atoms in optical lattices
• Transition from a strongly interacting 1D superfluid to a Mott insulator
• Quantum phases in an optical lattice
• Keldysh technique and non-linear sigma-model: basic principles and applications
• Momentum-Resolved Bragg Spectroscopy in Optical Lattices
• Cold Bosons in Optical Lattices
• Dynamical properties of ultracold bosons in an optical lattice
• Non-equilibrium Gross-Pitaevskii dynamics of boson lattice models
• Correlated bosons on a lattice: Dynamical mean-field theory for Bose-Einstein condensed and normal phases
• Quantum Phase Diagram of Bosons in Optical Lattices
• Spectral weight redistribution in strongly correlated bosons in optical lattices
• Process chain approach to the Bose-Hubbard model: Ground-state properties and phase diagram
• Effective Action Approach for Quantum Phase Transitions in Bosonic Lattices
• Visibility of Cold Atomic Gases in Optical Lattices for Finite Temperatures
• Spatially-antisymmetric localization of matter wave in a bichromatic optical lattice
• Nonlinear dynamics of ultracold gases in double-well lattices
• A New Time Contour for Equilibrium Real-Time Thermal Field Theories (7 characters altered for email)

Cited by in corpus (12)

• The `Higgs' Amplitude Mode at the Two-Dimensional Superfluid-Mott Insulator Transition
• Excitation dynamics in a lattice Bose gas within the time-dependent Gutzwiller mean-field approach
• Numerical and variational solutions of the dipolar Gross-Pitaevskii equation in reduced dimensions
• Schwinger-Keldysh approach to out of equilibrium dynamics of the Bose Hubbard model with time varying hopping
• Excitation Spectra of Bosons in Optical Lattices from Schwinger-Keldysh Calculation
• Light-cone like spreading of single-particle correlations in the Bose-Hubbard model after a quantum quench in the strong coupling regime
• Ginzburg-Landau Theory for the Jaynes-Cummings-Hubbard Model
• Quantum magnetism of ultracold atoms with a dynamical pseudospin degree of freedom
• Interpolating relativistic and non-relativistic Nambu-Goldstone and Higgs modes
• Improving Mean-Field Theory for Bosons in Optical Lattices via Degenerate Perturbation Theory
• Contour-time approach to the Bose-Hubbard model in the strong coupling regime: Studying two-point spatio-temporal correlations at the Hartree-Fock-Bogoliubov level
• Finite-temperature degenerate perturbation theory for bosons in optical lattices