Collisionally inhomogeneous Bose-Einstein condensates with binary and three body interactions in a bichromatic optical lattice

TL;DR

This paper investigates how spatially inhomogeneous binary and three-body interactions affect the stability and localization of Bose-Einstein condensates in a bichromatic optical lattice, revealing conditions for stability and collapse.

Contribution

It introduces the effects of collisionally inhomogeneous binary and three-body interactions on BEC stability in a bichromatic lattice, highlighting the role of interaction sign reversal and balance.

Findings

Reversal of interaction sign prolongs BEC stability.

Imbalance between interactions leads to collapse or multi-site occupation.

Weak three-body interactions increase BEC instability.

Abstract

We study the impact of collisionally inhomogeneous binary and three body interaction on Bose-Einstein condensates (BECs) of a dilute gas in a bichromatic optical lattice. We observe that the localized matter wave density which decreases after the introduction of repulsive spatially inhomogeneous binary interaction can be sustained by the addition of constant attractive binary strength in equal amounts. If the balance between repulsive spatially inhomogeneous binary interaction and constant attractive interaction is disturbed, the condensates collapse. Reversal of sign of interaction ensures the longevity of BECs. Any imbalance between attractive spatially inhomogeneous interaction and constant repulsive interaction either results in the collapse of BECs or in the occupation of the condensates at multiple sites on either sides. The introduction of a weak three body interaction in phase with the binary interaction increases the extent of instability of BECs. Reversing the sign of spatially inhomogeneous and constant interaction enhances the stability of BECs.