Dynamical phase diagram of Gaussian BEC wave packets in optical lattices

Abstract

We study the dynamics of self-trapping in Bose-Einstein condensates (BECs) loaded in deep optical lattices with Gaussian initial conditions, when the dynamics is well described by the Discrete Nonlinear Schrödinger Equation (DNLS). In the literature an approximate dynamical phase diagram based on a variational approach was introduced to distinguish different dynamical regimes: diffusion, self-trapping and moving breathers. However, we find that the actual DNLS dynamics shows a completely different diagram than the variational prediction. We numerically calculate a detailed dynamical phase diagram accurately describing the different dynamical regimes. It exhibits a complex structure which can readily be tested in current experiments in BECs in optical lattices and in optical waveguide arrays. Moreover, we derive an explicit theoretical estimate for the transition to self-trapping in excellent agreement with our numerical findings, which may be a valuable guide as well for future studies on a quantum dynamical phase diagram based on the Bose-Hubbard Hamiltonian.

References in corpus (4)

• Quantum Simulation of Antiferromagnetic Spin Chains in an Optical Lattice
• Some remarks on the coherent-state variational approach to nonlinear boson models
• Optical gap solitons and truncated nonlinear Bloch waves in temporal lattices
• Photon-atomic solitons in a Bose-Einstein condensate trapped in a soft optical lattice

Cited by in corpus (4)

• Negative mass hydrodynamics in a Spin-Orbit--Coupled Bose-Einstein Condensate
• Observation of a Transition Between Dynamical Phases in a Quantum Degenerate Fermi Gas
• Relaxation and coarsening of weakly-interacting breathers in a simplified DNLS chain
• Stationary and traveling solitons via local dissipations in Bose-Einstein condensates in ring optical lattices