Few-boson tunneling dynamics of strongly correlated binary mixtures in a double-well

TL;DR

This paper investigates the complex tunneling behaviors of strongly correlated binary bosonic mixtures in a double-well potential, revealing how inter- and intra-species interactions influence dynamics, including phenomena like self-trapping and species separation.

Contribution

It provides a detailed analysis of many-body tunneling dynamics using the MCTDH method, highlighting the effects of interactions and initial states on correlated tunneling and species separation.

Findings

Inter-species interactions increase tunneling periods similar to quantum self-trapping.

Intra-species repulsion can suppress or enhance tunneling depending on correlations.

Identification of correlated tunneling and species separation mechanisms.

Abstract

We explore the tunneling dynamics of strongly correlated bosonic mixtures in a one-dimensional double-well. The role of the inter- and intra-species interactions and their interplay is investigated using the numerically exact Multi-Configuration Time dependent Hartree (MCTDH) method. The dynamics is studied for three initial configurations: complete and partial population imbalance and a phase separated state. Increasing the inter-species interaction leads to a strong increase of the tunneling time period analogous to the quantum self-trapping for condensates. The intra-species repulsion can suppress or enhance the tunneling period depending on the strength of the inter-species correlations as well as the initial configuration. Completely correlated tunneling between the two species and within the same species as well as mechanisms of species separation and counterflow are revealed. These effects are explained by studying the many-body energy spectra as well as the properties of the contributing stationary states.