Signatures of non-trivial pairing in the quantum walk of two-component bosons

TL;DR

This paper investigates how strongly interacting two-component bosons in a one-dimensional lattice exhibit non-trivial onsite pairing signatures during quantum walks, revealing complex bound states influenced by intra- and inter-component interactions.

Contribution

It demonstrates the formation of onsite inter-component bound states and reveals re-entrant behavior in quantum walks based on interaction ratios, a novel insight into bosonic pairing dynamics.

Findings

Onsite inter-component bound states form during quantum walks.

Re-entrant behavior observed as a function of inter-component interaction.

Favored pairing depends on the number of particles and interaction ratios.

Abstract

Nearest neighbour bosons possessing only onsite interactions do not form onsite bound pairs in their quantum walk due to fermionization. We obtain signatures of non-trivial onsite pairing in the quantum walk of strongly interacting two component bosons in a one dimensional lattice. By considering an initial state with particles from different components located at the nearest-neighbour sites in the central region of the lattice, we show that in the dynamical evolution of the system, competing intra- and inter-component onsite repulsion leads to the formation of onsite inter-component bound states. We find that when the total number of particles is three, an inter-component pair is favoured in the limit of equal intra- and inter-component interaction strengths. However, when two bosons from each species are considered, inter-component pairs and trimer are favoured depending on the ratios of the intra- and inter-component interactions. In both the cases, we find that the quantum walks exhibit a re-entrant behaviour as a function of inter-component interaction.