Real-time Ginzburg-Landau theory for bosons in optical lattices

2010/03/22 by T. D. Grass, T. D. Graß, F. E. A. dos Santos +2
Physics and Astronomy · #Boson #Cold Atom Physics and Bose-Einstein Condensates #Formalism (music) #Lattice (music) #Nonlinear Photonic Systems #Optical lattice #Phase transition #Quantum #Quantum phase transition #Quantum, superfluid, helium dynamics #Superfluidity #cond-mat.quant-gas

paper · pdf · doi:10.1134/s1054660x11150096

published as Laser Phys. 21, 1459 (2011)

arxiv created 2010/03/22 · openalex publication_date 2011/06/23 · arxiv updated 2011/07/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

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.

Citations

• Nonequilibrium Gross-Pitaevskii dynamics of boson lattice models
• Transition from a Strongly Interacting 1D Superfluid to a Mott Insulator
• Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms
• Spectral weight redistribution in strongly correlated bosons in optical lattices
• Nonlinear dynamics of ultracold gases in double-well lattices
• Quantum phase diagram of bosons in optical lattices
• Dynamical properties of ultracold bosons in an optical lattice