Tunneling dynamics of few bosons in a double well

TL;DR

This paper explores the tunneling behavior of a few bosons in a one-dimensional double well, revealing complex dynamics from weak to strong interactions, including pair tunneling and multi-band Rabi oscillations, explained through exact spectrum analysis.

Contribution

It provides a detailed analysis of few-boson tunneling dynamics beyond the two-mode approximation, emphasizing the role of two-body correlations and spectrum analysis.

Findings

Transition from Rabi oscillations to pair tunneling with increasing interaction

Emergence of multi-band Rabi oscillations in the strong correlation regime

Skewing the double well influences tunnel resonances

Abstract

We study few-boson tunneling in a one-dimensional double well. As we pass from weak interactions to the fermionization limit, the Rabi oscillations first give way to highly delayed pair tunneling (for medium coupling), whereas for very strong correlations multi-band Rabi oscillations emerge. All this is explained on the basis of the exact few-body spectrum and without recourse to the conventional two-mode approximation. Two-body correlations are found essential to the understanding of the different tunnel mechanisms. The investigation is complemented by discussing the effect of skewing the double well, which offers the possibility to access specific tunnel resonances