Study of the inter-species interactions in an ultracold dipolar mixture

TL;DR

This study explores how dipole-dipole interactions affect inter-species dynamics in an ultracold erbium-dysprosium mixture, using experimental tuning and theoretical modeling to predict interaction bounds and phase behaviors.

Contribution

It introduces a combined experimental and theoretical approach to control and understand inter-species dipolar interactions in heteronuclear quantum gases.

Findings

Dipole orientation tuning affects inter-species cloud displacement.

Predicted bounds for inter-species scattering length $a_{12}$.

Framework for exploring dipolar phase diagrams and exotic states.

Abstract

We experimentally and theoretically investigate the influence of the dipole-dipole interactions (DDIs) on the total inter-species interaction in an erbium-dysprosium mixture. By rotating the dipole orientation we are able to tune the effect of the long-range and anisotropic DDI, and therefore the in-trap clouds displacement. We present a theoretical description for our binary system based on an extended Gross-Pitaevskii (eGP) theory, including the single-species beyond mean-field terms, and we predict a lower and an upper bound for the inter-species scattering length $a_{12}$. Our work is a first step towards the investigation of the experimentally unexplored dipolar miscibility-immiscibility phase diagram and the realization of quantum droplets and supersolid states with heteronuclear dipolar mixtures.