Anomalous supersolidity in a weakly interacting dipolar Bose mixture on a square lattice

TL;DR

This paper predicts that a binary dipolar Bose mixture on a square lattice can exhibit supersolidity at weak dipolar interactions, with robust phases and a first-order transition to superfluidity, making it experimentally accessible.

Contribution

It provides the first mean-field phase diagram showing supersolidity at weak dipolar interactions in a binary Bose mixture on a square lattice.

Findings

Supersolidity occurs at weak dipolar interactions.

Supersolid phases are extensive in parameter space.

A first-order transition exists between supersolid and superfluid phases.

Abstract

We calculate the mean-field phase diagram of a zero-temperature, binary Bose mixture on a square optical lattice, where one species possesses a non-negligible dipole moment. Remarkably, this system exhibits supersolidity for anomalously weak dipolar interaction strengths, which are readily accessible with current experimental capabilities. The supersolid phases are robust, in that they occupy large regions in the parameter space. Further, we identify a first-order quantum phase transition between supersolid and superfluid phases. Our results demonstrate the rich features of the dipolar Bose mixture, and suggest that this system is well-suited for exploring supersolidity in the experimental setting.