Quantum lattice solitons in ultracold bosons near Feshbach resonance

TL;DR

This paper explores quantum lattice solitons formed by two ultracold bosons near Feshbach resonance, showing how their properties can be tuned via detuning and how molecule creation affects their stability and existence.

Contribution

It introduces a detailed analysis of quantum lattice solitons near Feshbach resonance, highlighting the effects of detuning and molecule creation on their properties.

Findings

Binding energy, effective mass, and width can be manipulated by detuning.

Molecule creation stabilizes solitons in attractive interactions.

Bright solitons can exist with repulsive interactions within certain detuning ranges.

Abstract

Quantum lattice solitons in a system of two ultracold bosons near Feshbach resonance are investigated. It is shown that their binding energy, effective mass, and spatial width, can be manipulated varying the detuning from the Feshbach resonance. In the case of attractive atomic interactions, the molecule creation stabilizes the solitons. In the case of repulsive interactions, the molecule creation leads to the possibility of existence of bright solitons in some interval of detunings. Due to quantum fluctuations the soliton width is a random quantity. Its standard deviation is larger than the mean value for such a small number of particles.