Compacton existence and spin-orbit density dependence in Bose-Einstein condensates

TL;DR

This paper demonstrates the existence and stability of density-dependent spin-orbit coupled compacton matter waves in Bose-Einstein condensates within optical lattices, highlighting their potential for indirect measurement applications.

Contribution

It introduces the concept of SOC-compactons in BECs with density-dependent SOC parameters and analyzes their stability and conditions for existence.

Findings

SOC-compactons exist in binary BEC mixtures with balanced interactions.

Stability is influenced by density imbalance and SOC parameters.

SOC restricts but also signals the parameter range for stable compactons.

Abstract

We demonstrate the existence of compactons matter waves in binary mixtures of Bose-Einstein condensates (BEC) trapped in deep optical lattices (OL) subjected to equal contributions of intra-species Rashba and Dresselhaus spin-orbit coupling (SOC) under periodic time modulations of the intra-species scattering length. We show that these modulations lead to the rescaling of the SOC parameters that involve the density imbalance of the two components. This gives rise to a density-dependent SOC parameters strongly influence the existence and stability of compacton matter waves. The stability of SOC-compactons is investigated both by linear stability analysis and by time integrations of the coupled Gross-Pitaevskii equations. We find that SOC restricts the parameter ranges for stable stationary SOC-compacton existence but, on the other side, it gives a more stringent signature of their occurrence. In particular, SOC-compactons should appear when the intra-species interactions and the number of atoms in the two components are perfectly balanced (or close to being balanced for metastable cases). The possibility to use SOC-compactons as a tool for indirect measurements of the number of atoms and/or the intra-species interactions, is also suggested.