Driven dipole oscillations and the lowest energy excitations of strongly interacting lattice bosons in a harmonic trap

TL;DR

This paper demonstrates that analyzing the time evolution of site and momentum mode occupations in driven dipole oscillations of trapped lattice bosons reveals the system's lowest energy excitations, linking dynamics to the single-particle spectrum.

Contribution

It introduces a method to determine the lowest one-particle excitation energies of strongly interacting lattice bosons through their dynamical response under driven oscillations.

Findings

Time evolution analysis identifies lowest excitation energies.

Single-particle solutions guide the analysis method.

Rich dynamical responses observed with multiple particles and lattice.

Abstract

We show that the analysis of the time evolution of the occupation of site and momentum modes of harmonically trapped lattice hard-core bosons, under driven dipole oscillations, allows one to determine the energy of the lowest one-particle excitations of the system in equilibrium. The analytic solution of a single particle in the absence of a lattice is used to identify which function of those time-dependent observables is best fit for the analysis, as well as to relate the dynamic response of the system to its single-particle spectrum. In the presence of the lattice and of multiple particles, a much richer and informative dynamical response is observed under the drive.