Dynamics of cold bosons in optical lattices: Effects of higher Bloch bands

TL;DR

This paper investigates how higher Bloch bands influence the dynamics of cold bosons in optical lattices, revealing that parameter renormalization affects phase diagrams and dynamical responses, with implications for current experiments.

Contribution

It introduces an extended multiorbital Bose-Hubbard Hamiltonian accounting for higher Bloch bands and analyzes its impact on dynamical properties in optical lattices.

Findings

Parameter renormalization depends on system dimension.

Mean field phase diagrams do not scale with lattice coordination.

Higher bands significantly affect quench dynamics and energy absorption.

Abstract

The extended effective multiorbital Bose-Hubbard-type Hamiltonian which takes into account higher Bloch bands, is discussed for boson systems in optical lattices, with emphasis on dynamical properties, in relation with current experiments. It is shown that the renormalization of Hamiltonian parameters depends on the dimension of the problem studied. Therefore, mean field phase diagrams do not scale with the coordination number of the lattice. The effect of Hamiltonian parameters renormalization on the dynamics in reduced one-dimensional optical lattice potential is analyzed. We study both the quasi-adiabatic quench through the superfluid-Mott insulator transition and the absorption spectroscopy, that is energy absorption rate when the lattice depth is periodically modulated.